Almost as old as dirt, the Harley-Davidson XR-750 flat-track race bike was introduced in 1970 and the design has endured to this day. Technical Editor Kevin Cameron and Editor-in-Chief Mark Hoyer dive into the origins of the XR-750, its evolution, and how it is still capable of winning national races five decades later. They'll also cover the universality of dirt.
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SportsTranscript
00:00:00Welcome back to the CycleWorld podcast. I'm Mark Hoyer. I'm the editor-in-chief and I'm with Kevin Cameron, our technical editor.
00:00:08We've done more than 30 episodes. Thanks for riding with us.
00:00:13This episode is brought to you by Octane Lending. It's our parent company.
00:00:18We'll put a link in the description.
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00:00:42So, thank you.
00:00:46This week's episode is
00:00:48The Harley-Davidson XR750. Legendary dirt track bike. Amazingly beautiful motorcycle.
00:00:57I like dirt track bikes because of how simple they are.
00:01:02Exactly. And how elegant they are. I like dirt track racing
00:01:08because it's on dirt.
00:01:10And it's, what is it? It's like the universal. It's the constant. Dirt is the constant. Even though dirt is highly variable,
00:01:19you know, traction on dirt sort of never exceeds
00:01:22something. Like no matter what you do to the tires, no matter what you do to the bike,
00:01:26there's only a certain amount of traction available.
00:01:29And I think that's how dirt track is such an elegant sport.
00:01:34I mean violent and amazing, but also elegant. What Willie G told me at
00:01:40Del Mar, the Del Mar Mile in
00:01:432000,
00:01:45mile racing is some of the best. It's the best racing in the world.
00:01:50And I think the mile, I mean, I love the mile because it's so fast and the draft and all that stuff.
00:01:55It is really cool. But it was it was neat to be there.
00:01:59Let's talk about the XR750, Kevin.
00:02:02Well,
00:02:03the first time I saw one, I was struck by the fact that
00:02:08the front and rear wheels were as physically close to the engine as they could be.
00:02:14If the front fork were moved back a quarter of an inch, the wheel, the front wheel, would move up and hit something on the engine
00:02:22at full bump. And
00:02:24in the rear,
00:02:26there was hardly any distance between the swing arm pivot shaft and the front of the rear tire. So
00:02:34very
00:02:35packed together to get the shortest possible wheelbase, which of course we know
00:02:41translates to
00:02:43rapid turning. And
00:02:45as you said, it was a simple motorcycle because
00:02:51to the highest degree, it represented two wheels, an engine, and a place to sit.
00:02:58So
00:03:02it's hard to get any simpler than that without doing away with one of the cylinders, but that's another story altogether. I
00:03:09think
00:03:11everyone started out with V-twins around
00:03:141910 because it was the easiest way to get more power when the singles that you were already building had
00:03:22been maxed out. So you just
00:03:25change your crankcase
00:03:27casting cores a little bit to provide a second cylinder pad as
00:03:32close to the first one as was convenient. For Indian, that was 42 degrees. For Harley, 45.
00:03:39And you
00:03:41just stuck a second cylinder on there. And
00:03:46the engine still had a single crank pin and
00:03:50the connecting rods were fork and blade where they went on to the crank pin. So one connecting rod
00:03:57was the fork and the blade fitted between and there were roller races
00:04:04between the rods and the crank pin. So
00:04:09that's the origin of the V-twin, the simplest way to build a
00:04:15more powerful bike, a more powerful engine than a single.
00:04:19You know what I appreciate about doing these talks with you, doing this show with you, Kevin, is that
00:04:24we can always go back to the Big Bang.
00:04:26It doesn't matter if we talk about metals and it's like the molecules that, you know, it's really cool.
00:04:35But it's nice. Well, I think though that
00:04:38Harley riders like to feel that they're part of a great tradition and it does go way back.
00:04:46That's just what Glenn Curtis did when
00:04:50he could see that his singles weren't going to win the races that he was running. So he added a second cylinder and
00:04:58when the carburetion for the
00:05:01second cylinder was rich, he drilled a hole in its intake
00:05:06manifold to lean it out, just sucked in air.
00:05:10And these were very rough and ready developments. You want more power? More cylinders.
00:05:17And Jim Fueling wasn't the first person to build a W, but it's the obvious next step beyond the V-twin. Yeah, Jim Fueling,
00:05:26legendary guy, developer.
00:05:29He did work for GM, made GMs make a lot of power and did a lot of work for Harley-Davidson and
00:05:36exhaust port design, which was one of the things that he sort of built his tank collection on
00:05:42doing exhaust port optimization, making the exhaust port as small as possible
00:05:47to get the flow so the heat didn't go into the cylinder head. And
00:05:51he helped Harley with that on
00:05:54various points in development. And what Kevin's talking about is a
00:05:58Fueling W3, which was adding a third cylinder to a Harley-Davidson.
00:06:03And I road-tested one of those years ago, rode it all around and was hammering it. His shop was in Ventura.
00:06:09I was riding back roads and they're like, yeah, take off, do whatever you want. So I just rode around and
00:06:14was hammering the daylights out of it. And then I smelled oil and I pulled over and there was oil coming out the breather and
00:06:22I'd been riding it very hard because that's what I'm supposed to do.
00:06:25I'm supposed to find problems and just rattle around and ride to the grocery store. You don't find problems.
00:06:31And so I called him on the phone and I called not Jim,
00:06:34but I called Jim's guy who kind of set me loose and I'm like, hey, man,
00:06:37we're getting a little bit of oil out of here. There's some oil on the back tire. The breather's, you know, going.
00:06:41He's like, oh good. It means you're hammering it.
00:06:46He was fine with it. I think, you know, sidebar, I think during development, especially on big twins that
00:06:55breather control seems always to be a problem at some point and it takes a little bit to figure it out.
00:07:01No question about that because you have
00:07:04two big pistons that are moving almost together.
00:07:07And so the
00:07:10volume under the pistons is quite large at top center and it gets a lot smaller at bottom center and that
00:07:17rushing of air goes up and down the pushrod tubes and it can just, it can cause oil
00:07:25to accumulate in places you would never dream of it's getting to.
00:07:29Yeah, that's a possible show.
00:07:32Oh, no question. No question about it because, yeah, oil control in the cylinders. They want
00:07:39to, what they need most of all to prevent in these engines that have their flywheel inside the crankcase is
00:07:47called wet sumping. When the oil scavenge system that is picking up
00:07:52the oil from the bottom of the engine and returning it to the oil tank
00:07:56cannot keep up with the accumulation and then
00:08:01the crankshaft whips that oil around in the tight-fitting crankcase and
00:08:07this becomes a
00:08:10high-speed
00:08:11viscosity measuring apparatus.
00:08:14And by golly that viscosity turns into heat in a big hurry as
00:08:21Dick O'Brien, Long, Harley's
00:08:25racing manager
00:08:26said on one occasion, he said you could you could see it on the straightaway at Daytona.
00:08:32When that, when it would start wet sumping, it was like a giant invisible hand came down and just said
00:08:39no, you don't and the bike just
00:08:43Oh, and so much heat, right? Yeah
00:08:46Pushes your oil temperature out of out of sight because of course all that engine power is going straight into the oil at
00:08:53the rate of
00:08:56746 watts per horsepower
00:08:59So, oh I made a little experiment yesterday
00:09:02I stood over our kitchen toaster with my face about 18 inches above the slots and
00:09:10746 watts came up into my face one horsepower and I thought this is a graphic
00:09:15demonstration of what happens to front tires in MotoGP
00:09:20Because there
00:09:23The heat rejection is more than 300 horsepower
00:09:27That's 300 kitchen toasters all blowing on your motorcycle if you're drafting somebody
00:09:34so but that's
00:09:36Neither here nor there
00:09:38Yeah
00:09:41Talking to you Kevin
00:09:42I mean, I think it's it's why we do the show because we could sit down and we could write a really beautifully highly focused
00:09:48Story about the XR 750, but then we don't get toaster talk with Kevin Cameron. So
00:09:52And that's why I'm here
00:09:57There's a great little handbook that was written by Pete Zylstra who was the draftsman that the detail draftsman on
00:10:06the aluminum XR and
00:10:09Harley built
00:10:12Their first OHV
00:10:15race engine
00:10:18750 race engine for
00:10:211970 as a result of
00:10:23push and shove in the competition AMA's competition committee and
00:10:28They decided effective 1970. Everybody would get 750 cc's
00:10:35So for whatever reason Harley Davidson
00:10:40Made a 750 out of a Sportster engine
00:10:44With a lot of changes in a lot of details and
00:10:49the original Sportster of
00:10:511957 had iron cylinder heads and iron cylinders
00:10:55now
00:10:56Aluminum which we take for granted as the normal material to make cylinders and heads out of
00:11:02conducts heat four and one half times
00:11:06faster than cast iron
00:11:09That's a bunch
00:11:11so
00:11:13I'm not sure
00:11:15How they came to make that
00:11:171970 engine either they were between a rock and a hard place in getting 200 bikes
00:11:25For the beginning of the AMA season
00:11:29Or they thought well, it'll work on dirt track. We
00:11:34Can't expect to win Daytona with it. I don't know what they knew when the season started
00:11:40but
00:11:42Dick O'Brien told me at one point. He said if you finished a dyno run
00:11:49with the iron the
00:11:511970 iron motor and
00:11:53You happen to be on your way out. You turned off the lights in the test cell. You could see the heads
00:12:03Glowing dull red now
00:12:05if you want to know a
00:12:08Condition of an engine that encourages detonation it is glowing red hot
00:12:14you you you suck you suck fresh fuel air mixture into the cylinder and
00:12:22Place mind you the outside of the cylinder is glowing dull red. What's the inside doing? It's really in bad shape
00:12:28yep, so they got the Daytona that year and
00:12:32They
00:12:34Had to lower the compression ratio right down until it was as low as
00:12:39it was on the KR which by that time had been developed to 58 horsepower and it had basically just
00:12:46Killed the Triumph 500s a semi Elmore. Yeah
00:12:51750 flathead that's the care
00:12:54Buddy Elmore had won the 200 in
00:12:581966 on a 500 Triumph that was nearing its development limit and Gary Nixon
00:13:05won it in 67 and it was looking like this is this is Triumph Speedway here and
00:13:11Harley came up with a bunch of
00:13:16Really inspired
00:13:18Modifications that were the result of of men who had a lot of experience but didn't work for Harley Davidson
00:13:26At any rate they built these iron motors and they may they built 200 bikes and
00:13:33the story of the development from that point onward is
00:13:39Continuous change. Oh, this is breaking. Well, we we can make a larger radius here. It will be less sensitive
00:13:46Okay, that's solved. What's breaking now? Oh, no, there are three things that are breaking now. Oh
00:13:52We're having trouble with the with the connecting rod bearing we're having trouble with the piston rings and
00:13:59This was nothing strange to the aircraft engine industry, which had been building those
00:14:07horribly complicated
00:14:09radial air-cooled engines in the 1930s through the
00:14:13mid 50s
00:14:15every year they came up with more power and
00:14:19Gremlins came up with more failures
00:14:21so it was a constant process of fighting the power upward and trying to follow the power with
00:14:29Reliability and it makes fascinating reading for somebody who's done any of this kind of work. I looked at their a
00:14:38photograph of the bearing cages that they began to make
00:14:42for their
00:14:44XR engine and
00:14:47They look just like the bearing cages that I made for my 750 in 1972 no, that's satisfying
00:14:54They did it a little differently and I thought oh, that's clever if I had my life to live over again
00:15:01That's how I do it
00:15:03But a lot of talented people working on this thing and not all of them working for Harley-Davidson
00:15:10Dealers had their own dinos
00:15:12These were these were days when well-equipped dealers had their own racing programs. They had their own riders
00:15:19It was such enthusiasm for motorcycles
00:15:23Through the 1970s. That was the that was the golden age when the numbers were huge
00:15:29Well, I I wish this is a shit. What is this? Hey Moto America?
00:15:35Bagger racing is awesome
00:15:37We need double the bikes on the grid and you need to make it affordable for a dealer
00:15:42You need the big dealerships to be able to do exactly what Kevin said was happening in dirt track
00:15:47And the other thing is bagger racing is probably the worst thing that happened to dirt track in the last 20 years
00:15:54Just because of the focus it is it's popular. It's great
00:15:58You know, it's it's really sucking up resources. Yeah
00:16:02Yeah, well
00:16:06We can wish for things but only
00:16:09happenstance provides
00:16:12But I think that the XR 750
00:16:16Of course in 45 years on dirt track
00:16:21they won the championship so many times the real exception was the
00:16:27five or six times that the Honda RS 750
00:16:33With Honda's riders managed to take the championship and
00:16:38Everyone became so upset about this. Oh
00:16:41well
00:16:44This calls for action or something doesn't it? Well, no, it's called competition. I think
00:16:51It's not the obligation of the fast guys to slow down. It's the obligation of the slow guys to speed up
00:16:58Yeah, well, it's a it's a good story because in the day I was talking to my old boss who was pretty close with
00:17:06Bubba showbert and
00:17:08He said Bubba at the time when Bubba was winning. They told him don't win by too much
00:17:14So when you're when you're going he's on an rs-750 Bubba show was riding an rs-750 and he's going down the straight when he's pinned
00:17:21He's not pinned. He's holding just enough to stay just ahead so he doesn't get restricted
00:17:27It's like to win by just don't win by too much. Keep it in your pocket. Don't don't let anybody know what we got
00:17:34so
00:17:35They decided that they were going to have the late Jerry branch who had a dyno
00:17:42And was famous for being willing to use it
00:17:47He would run a series of tests with these engines and with various forms of restrictor
00:17:54To come up with a way of equalizing
00:17:58performance
00:18:00And I got chosen to go out and sit there
00:18:05just behind
00:18:06Jerry branch and watch this whole thing unfold
00:18:11and one of the things that he had that was just wonderful was he had a
00:18:17Very light suction blower and he would hook it up to the carburetor float bowl vents
00:18:23And he could pull the float bowl vents down a quarter of an inch of water in pressure and
00:18:30See the effect on power that is he didn't have to run in and out of the dyno room changing jets
00:18:36He could just say let's lean it down a little bit and see if we pick something up. Oh, no
00:18:40No, let's go the other way here. This looks good right here, and it saves a lot of time
00:18:47so and I saw it work and
00:18:50I also saw the Harley's
00:18:53Torque curve the engine would start to accept full throttle without
00:18:57popping and banging from about 55 to 5800 and
00:19:03it would rev on until
00:19:06the
00:19:08Dick O'Brien
00:19:09nervous point of 9200 rpm
00:19:12he didn't like to see all these privateers pushing the revs because
00:19:18He had seen all the stages in
00:19:22All of the parts in the engine that had been necessary at each step another 50 rpm
00:19:28Oh, well now you're going to have your garden will come up with weeds called problems and you'll have to pick those weeds out
00:19:38But the privateers, of course that the dictum in racing is if you don't win if you don't do well
00:19:45The people who are helping you will become interested in
00:19:50female mud wrestling or some other activity, so
00:19:56He tried to
00:19:58guys, please
00:20:00But they kept going down
00:20:02They started out with rollers big end rollers the big end of the connecting rod that were eight millimeters in diameter
00:20:10then they went to
00:20:13Six millimeters and then they went to five and the reason for this is that as the
00:20:20bearing on
00:20:21the big end goes round to perform the
00:20:25engine cycle the connecting rod is swinging from side to side and
00:20:31so the connecting rod is
00:20:34adding and subtracting
00:20:36About 25% to the speed of the crank pin bearing and the crank pin bearing
00:20:42Has only the contact of the rollers and the crank pin and rod
00:20:48To keep it following that speed that
00:20:51speed change
00:20:53When the rowers are too big and too heavy and the cage holding them
00:20:58Parallel to one another is too big and too heavy
00:21:02It can't follow anymore and the rollers begin to skid
00:21:08They scrape oil off of the friction the rolling surfaces and
00:21:14things go from bad to worse, so
00:21:18They had many steps to follow
00:21:23The motion as the engine revved up they had to make the
00:21:27Rowers in the crank pin bearing smaller and lighter and
00:21:31It was eventually the death of the XR 750
00:21:36Not because it wasn't fast
00:21:39But because it began to be unreliable in ways that were hard to fix, you know
00:21:47Chris Carr, you know, I spoke with Chris Carr in the
00:21:51one of those infield parking lots that
00:21:54In Annapolis, and he he said well, you know
00:21:58When I was a factory rider, they were giving me a new bottom-end
00:22:03every weekend
00:22:06And
00:22:08That meant having
00:22:11Cracks ready to go in the engine that had already been rebuilt and trued
00:22:17And
00:22:20Just carrying that stuff with them
00:22:23and
00:22:25That's not unusual in a
00:22:29very energetic fast developing
00:22:32Racing when the Italians began to get past 12,000 with their little 125 singles in the late
00:22:391940s they were changing cranks every every race meeting as well
00:22:45and there were a lot of
00:22:47Japanese Grand Prix bikes where they were using one crank for practice and another crank for the race
00:22:53so Harley and their XR had got into that rough territory and
00:23:00the decision then would be
00:23:03What if we put a plain bearing in this thing?
00:23:06Well, that's what I would wish for. You know, I I was at Santa Rosa when the FTR 750
00:23:14Joe Copp was racing that around it and it's kind of like
00:23:18you know a big debut and it was a
00:23:21Pretty messy track hard hard visibility and stuff Joe
00:23:24I had shout out to Joe because he's close to my age and he was hauling ass
00:23:29He was riding so fast
00:23:30But Brad Baker was there and he was he was running an XR 750 and his times were great and he was able to ride
00:23:37The cushion it was unbelievable. He was like riding high just clipping the hay bales on an XR 750 the
00:23:44You know, what do you say the emblematic?
00:23:48image of that situation was
00:23:50During one of the practices one of the heats or something Brad Baker's bike broke
00:23:55I was sitting with Terry Vance and he's like, you know, if we just develop this if we could do something to make it reliable
00:24:00It's fast enough. Yeah, we could just make it reliable
00:24:03Well, then, you know Brad's on a broken bike and Joe, I think it was Joe
00:24:07It was an FTR 750 had to had to be Joe it pushed him back to the pits
00:24:11Push Baker back to the pits and that was like to me that was the image of what was happening is like well
00:24:17We're not developing this but meant an XR it's a 45 that's what's good about it
00:24:22It's got that 45 and they can put it right up on the front wheel
00:24:26They can move the engine around to put put it where they want in the chassis because it's it's a 45
00:24:31It's not a 60. It's not a 90
00:24:34It's it's really neat. And then the flywheel mass and all that stuff. I mean
00:24:38you know the FTR might deserve its own program with its
00:24:42Liquid cooling its torque curve is a thing of beauty
00:24:46It had the variable mass has the variable mass flywheel, although I don't think they're allowed to vary the mass
00:24:54But
00:24:56Man, imagine imagine an updated XR take
00:24:59Taking all that you don't need gosh. You do you need to even change the chambers?
00:25:03I guess you would you you might make it four valve, but I do you need to I don't know. Yeah
00:25:08Well, they they went through a fabulous amount of work on the valve train and I
00:25:16Hadn't had no inkling of this but it was described in terms of the valve train
00:25:24spring rate and
00:25:28Basically what that is is you you measure
00:25:31How far you have to compress the pushrods
00:25:36twist the rocker arms and bend the twisted rocker arm tube and bend the arms and
00:25:44all of these parts flexing the
00:25:48Rocker arm pivot shaft is is bending
00:25:52And find out how much
00:25:56Motion there is on one side of the shaft
00:26:00Motion there is on one end without there being any motion at all on the other and you can quickly convert that into a
00:26:07Number and they started out at about ten thousand pounds per inch. That was the spring rate and
00:26:15they were able to when they
00:26:17when they started thinking along these lines, they were able to double that quite easily by
00:26:23Making the pushrods much heavier. They were aluminum thin wall things
00:26:28they just made the wall a whole bunch thicker and
00:26:32You would think oh, well, you don't want to add weight because that's gonna make a valves float
00:26:37But the fact is that when you make the valve train
00:26:42extra rigid it can handle a
00:26:47Spring rates there are a lot stiffer because the real load in opening and closing the valves is inertia
00:26:56and
00:26:57when you have a low spring rate, it means that the whole thing is is
00:27:01Compressing and expanding and the pushrods are our bow string and they're doing this
00:27:08That's why pushrods are often made so they're thicker in the middle than at the ends
00:27:13It makes them stiffer against that lateral bending
00:27:16Well, I also want them in a straight run like when you cross them over on a big twin
00:27:20If you have a big twin you can throw them out the side
00:27:23Yeah, and that was well that was kind of what this you know
00:27:26There's the trademark of the Sportster was having the cams and having them have straight pushrods up to the to the rockers
00:27:33Yes, and that was that was something that dated back to 1929. That was I
00:27:40Was sorry to see that go because it was such a Harley icon
00:27:45At any rate when you have a springy valve train that springing is going on the whole time
00:27:52so it's like you're
00:27:54Trying to measure for accurate carpentry with a ruler that is constantly going doing doing doing and yeah
00:28:04Something around six inches I I think
00:28:07It adds uncertainty to where the valve is and how fast it's moving at any given moment
00:28:14so if the valve train is is
00:28:18expanding just before
00:28:21The valve is seating you can imagine that the valve may bounce horribly
00:28:28I was told
00:28:31By a spintron operator Oh NASCAR used to allow five bounces after closure, but then they they cut it way back to three
00:28:40And of course, they're working with
00:28:43pushrods and rockers
00:28:45And the the most rugged
00:28:49Army tank looking parts are to be found in in
00:28:55Pro-stock automobile that the rocker arms are just wonderful looking
00:29:02Tremendously they're they're wonderful. I wish I had one now
00:29:07It's great. They're just these massive
00:29:11They're able in those cases to
00:29:15Wreck the springs in one drag strip run
00:29:19but of course in
00:29:21In dirt track, you've got to have an engine that stays together
00:29:25so the valve springs are not stressed to that level, but they still have to be of
00:29:32Remarkable quality and
00:29:35That was another long
00:29:37evolution throughout all those years of
00:29:40the XR so
00:29:43We
00:29:45Think in terms it's tempting to think in terms of
00:29:50standard soup up stuff as
00:29:52A means of winning races more compression greater airflow into the intake port
00:30:01But
00:30:03If the engine won't operate at the speed that's necessary to beat the competition
00:30:11Then you have to fix that is that the main bearings is that the rod bearings
00:30:17Are the Pistons cracking around the wrist pin boss?
00:30:21how about wrist pins breaking they experienced wrist pins breaking and
00:30:27What did they trace it to they traced it to little?
00:30:32machining
00:30:34marks on the inside of the wrist pin and
00:30:38And of course while everyone else is making wrist pins out of tool steel and vacuum remelted this and that
00:30:46one of their suppliers told Harley
00:30:49we're gonna make these out of low carbon and we're going to nitrogen harden them on the outside and the inside and
00:30:57Cramming all those nitrogen atoms into the surface of the steel puts everything
00:31:02Into compression he smashed his face for you listening on Spotify Kevin just smashed his face. It was awesome
00:31:11Demonstrating compression
00:31:12Putting things into compression means you have to bend them a lot more to relieve the compression and go into the tension
00:31:19that can create cracking and those low-tech but nicely finished and
00:31:26hardened inside and out wrist pins proved to be reliable and
00:31:30This is the lovely thing about this kind of work and this kind of documentation because it shows you that
00:31:38Life is not on the drawing
00:31:42The drawing is a tremendous abstraction from the actual
00:31:47Human work that's involved in making the thing on the drawing
00:31:53finish the race and
00:31:55When you take away the people who knew how to do that and you leave behind only the drawing
00:32:03That's all you have is a sketch. Well, it was something like this
00:32:09Yeah, this happens over and over again when manufacturers go to China they think well
00:32:15It's all on the drawing the Chinese make what's on the drawing and it doesn't work. Oh
00:32:20Well, we forgot to tell you
00:32:22We'll send the guy over that understands
00:32:25institutional knowledge
00:32:28What's that story? Was it the was it the BSA factory? They moved a factory and
00:32:34The crankshafts weren't coming. There was a chatter. Oh, yeah, and then they found the guy who was operating the machine
00:32:40It was dark and they Norton and they brought him in. Yeah, they brought him in and he looks at looks at the machine
00:32:45He's like boy, where's me stick and they're like what?
00:32:50And he had a stick with like a
00:32:53Rounded kind of worn edge in it and when the shiny and shiny and when yeah, yeah when the crank went in the machine
00:33:00He pulled that stick against the shaft so that it wouldn't have a bearing clearance. Yeah
00:33:06They got they got in there in their
00:33:10Terrible little English car and drove back to Bracebridge Street and he kind of poked around and oh there it is there
00:33:16And they took it back and he used the stick and demonstrated how he could produce. I think they were boring cases
00:33:26How he could use it to produce an on spec bearing counterbore and
00:33:34This is this is what happens when
00:33:38the people in charge of the budget
00:33:41Throw up their hands. Oh
00:33:43This machines been doing giving excellent services since
00:33:481917 there's no need to change it. Thank you. All right. Well, we'll manage
00:33:57So, I think all that all that wonderful glory all those closely fought races bikes sideways
00:34:06closely packed through turns
00:34:10The motorcycle
00:34:13Had to be
00:34:16Made into something that hardly came to the riders attention. You didn't want the motorcycle
00:34:23Diverting the riders attention from the people on both sides and before and behind
00:34:29because his job was to engage the enemy more closely and the motorcycle should take care of itself and
00:34:37They managed to do that
00:34:40Far more often than not and I think that it was quite a
00:34:45quite an odyssey of
00:34:50Constantly rising
00:34:52mechanical competency
00:34:55Mechanical competency and then the people who are running it like Bill Werner and and you know
00:34:59All the tuners who had so much knowledge of somebody like Chris Carr
00:35:03Talking to Chris Carr at Santa Rosa
00:35:06Walking around the track and seeing some they were doing some demonstration laps on
00:35:10On the FTR and and Chris was talking to us about the track and all the the different
00:35:16You know aspects of flat track racing
00:35:19And we were talking about the XR still racing. I'm like Brad's just like how does he ride that cushion and he's like
00:35:24Well, he's got a tremendous large pair of etc. And I'm like, oh, of course. Well, that's that's part of it
00:35:30But he doesn't do it unknowingly, you know
00:35:33He's not just twisting it because he's brave he's maybe is brave, but he's also incredibly talented
00:35:40But he was anyway, he was talking about the gearing
00:35:44You know the number of gears that you had available
00:35:47You just had all of these gears and he was he was saying like sometimes I would gear my bike
00:35:53Knowing that I'm going to be in striking distance or putting myself in striking distance on the last lap
00:35:59And I don't want to get drafted to the line
00:36:01I'm gonna drop them to the line and I'm gonna gear my bike for that specific
00:36:09point in the race to win
00:36:11From rolling on to get across the line and not have to shift or whatever and maybe take that rpm to 10 something
00:36:19Not just 98 or whatever. I'm gonna have that little extra to get them and
00:36:24To be right where it needed to be and that kind of experience
00:36:28With a product, you know with an XR 750 and knowing all those details and having it expressed in a race win
00:36:35That I did it because I did point zero eight different difference in the gearing. Yeah to me
00:36:44That's just amazing. I think these people are doing it every weekend and they they see patterns and they think oh
00:36:53Why don't I try this it works
00:36:57Then it becomes
00:36:59Part of that riders bag of tricks, you know, we used to do that Nixon used to put on a lower first
00:37:06where
00:37:07getting off the last corner would be
00:37:10he would kill him there and
00:37:14You have to have different ratios
00:37:17for every gear in the transmission, of course and
00:37:21any factory
00:37:23Does that?
00:37:26in in the case of MotoGP the
00:37:292027 rules will allow
00:37:32four different alternate primary ratios
00:37:36now the reason people would change primary ratio is because
00:37:42Once you had the anti-squat
00:37:45worked out for the back of your bike so that when you gas it the bike did not squat down and push the front or
00:37:52suddenly top and stop and
00:37:55With unload the tire with a click but instead was in the working range
00:38:03When you had it working like that if you had to change the gearing
00:38:07you'd be changing the angle of the top run of the chain to the central plane of the swing arm and
00:38:16by changing the primary ratio you could
00:38:21Compensate
00:38:23Leave leave the rear alone
00:38:26where the angle is the way you want it and change the gearing with the primary ratio and it just
00:38:33people being driven crazy
00:38:35thinking about this stuff while they're trying to sleep and
00:38:39suddenly sitting up
00:38:41uh-huh, big light bulb moment and
00:38:46Racing successes is a
00:38:50Big old hefty trash bag filled with those
00:38:53big light bulb moments that people have remembered because they're so
00:38:58Important in a very little place. Yep. I just got a who knows why I
00:39:04Just I don't know. Yeah, the chain pull thing is really interesting because
00:39:09That leverage, you know the distance of the chain from the from the axle and from the swing arm pivot
00:39:15How much is it pulling and you want just enough?
00:39:18You don't want it to squat no no
00:39:20No
00:39:20But you also don't want it to top out as you say and you want just enough chain pull
00:39:24To have the bike be able to finish the corner in a nice way
00:39:28Yeah, and that's what you're after and then I think about changing the primary ratio
00:39:32And then you're gonna spin the clutch at a different speed and how much effect does that have on what we're doing?
00:39:37I guess they're not really using clutches
00:39:40at all basically, but it would change the effect of
00:39:45The way the clutch operates the way that well that was when when slipper clutches were all there was
00:39:54And the slipper clutch was originally invented at Honda among other places before the NR 500
00:40:04The slipper clutch really needs a different setting for every ratio in the gearbox and
00:40:11It was Colin Edwards that made this clear to me because
00:40:16I'm wandering around in the days in the in the pit area at
00:40:21Motegi in
00:40:232003 and he came up to me and he said come with me. Let's find some place where we can talk
00:40:29I've got some cool stuff. You'd like to hear about he was always great to talk to you
00:40:36And we went and sat on the sat on the pit wall and he told me
00:40:41when he was riding the
00:40:44Aprilia cube, which was designed the engine was designed by Cosworth
00:40:49that
00:40:50They say, okay. We've got these turns down
00:40:54Far as the slippers concerned now
00:40:56We've got to make a little change because it made it worse in turn whatever turn three
00:41:02So he said they they take out an 8,000 shim and put in a 5,000 and everything would be different a
00:41:11whole new set of problems had come about because of of
00:41:163,000 of an inch in shim stack height
00:41:21So no wonder they had to come up with
00:41:24Engine braking control. Yeah, and I heard it working at Motegi
00:41:32I'm thinking to myself
00:41:35These engines are developing power all the way to the apex. What's going on here? And
00:41:41I went to see Kenny and Kenny said come in my garage here
00:41:45And he showed me how
00:41:48the computer
00:41:50The computer
00:41:53Was given instructions which came in through the laptop
00:41:58That said in in XYZ corner in whichever
00:42:04situation
00:42:05You will cancel this much of engine braking by opening the throttle this many degrees
00:42:11So basically they were just using a little fuel
00:42:15To cancel engine braking and they could tailor it
00:42:19Not only to each ratio but to any corner or other situation on the racetrack
00:42:25Here's the the barn job version of that as I was at a racetrack with Roland Sands and I was riding like a super sport
00:42:32600 and I was going into corners and I'm like man the engine braking it's like it's too much going into this turn
00:42:38You know, I just can't it's just it's too much the bikes unstable at the back and he's like dude turn up the idle
00:42:46Yeah
00:42:47It's like mind blown, you know, that's what those those first
00:42:53those superbike pioneers on those big
00:42:561000 CC bikes that were
00:42:59they had double the power of the previous generation of motorcycles was like a Bonneville with two engines and
00:43:06in the Bonneville frame with Bonneville brakes and and tires and
00:43:11Yes, there were problems but in overcoming them
00:43:16the second generation of
00:43:18sport bikes which began with
00:43:22Honda Interceptor in 1983 was a direct result of
00:43:28the problems encountered between
00:43:301975 and
00:43:321982
00:43:33With those big thousand CC sit-ups they had to fix so many things
00:43:39Why don't we make them already fixed at the factory and that's called a better motorcycle and
00:43:46Yes
00:43:48Racing does improve the breed because it makes
00:43:51people focus on
00:43:53What's good and what's working against you? What part of this motorcycle is my enemy?
00:44:00Let's defeat it. Let's give it
00:44:03Candy bars. It's something to divert its attention away from screwing up our lap times
00:44:08And the challenge there is the communication from the racing department to production
00:44:13Yeah, and that that's I think one reason a company like Honda
00:44:19stirs it around all the time and you get you get or Ike
00:44:23Who worked in?
00:44:25Racing Grand Prix racing and he becomes a large project leader for the CBR 600 f4i
00:44:32Yeah, and you get that guy with that expertise and that global view and they always did that they moved guys around
00:44:38You know, it was like two years over here and two years over here
00:44:41Happening Harley. Yeah, the XR. Yeah
00:44:45when they started with that
00:44:471970 iron
00:44:49XR it had a five-piece crankshaft two main shafts
00:44:54Fitted into the flywheels with a taper and a key and held by a nut
00:45:01the crank pin tapers and nuts and
00:45:04And
00:45:06The rods I wanted that that was on my list of I've got to ask Kevin like I can't believe
00:45:12They were doing this with a built-up crankshaft
00:45:15But if you have rollers and you have the rods that way I'm gonna get them on there. Yeah, you got to press it together
00:45:20that's why it should be plain bearing like let's get them back and
00:45:23You know, let's rededicate ourselves to grassroots racing. We're
00:45:29So
00:45:31The first thing they did, of course those shafts worked loose and then they welded them
00:45:38But they're only welded on one end. So there's all this wallowing and
00:45:43Trouble red fretting. I'm sure of it. Yes, and so then they decided
00:45:49What about forging the main shafts in one piece with the flywheels?
00:45:53No, you'd have to make it. I mean have to make it die
00:45:56Oh dear and all this sort of thing, but they did it and it worked
00:46:01And it was transferred to the big twin
00:46:05production engine
00:46:08Later because it needed the same
00:46:12guarantee of staying together and
00:46:15staying off of warranty reports
00:46:19So
00:46:20That was that was one
00:46:23big case in which it went straight from the race team
00:46:27to
00:46:29to production and there were numerous other examples of that because
00:46:38There was so much overlap between the race team
00:46:40The race team was constantly talking to the metallurgy guy. The metallurgy guy was there to serve production
00:46:49So there were specialists in different areas
00:46:53Who were called in to consult with the race team?
00:46:56There was continuous
00:46:59Diffusion of ideas among this whole population. They were the ideas were the free electrons the D localized
00:47:07electrons in
00:47:10Organization he's referring to the metals podcast that we did last week. So
00:47:16Or no or the week before but the metals podcast. Yeah, we were talking about this
00:47:22So that's it's a good throw go go listen to that one if you haven't
00:47:27I think that
00:47:29They probably didn't have much friction in the sense of corporate department
00:47:37Separation in those days at one time the racing department had like
00:47:43nearly 20 people in it and
00:47:46they had a shop for me they had a dedicated machinist and
00:47:51Almost all of the mechanics on the factory team
00:47:55Were competent at machine work. They could do welding. They could do fabricating these were
00:48:03not Joe's
00:48:05pulling parts
00:48:08And assembling stuff out of stock parts they were
00:48:13The people who remembering? Oh, yeah, I take the little rubber abrasive wheel and
00:48:18Knock this sharp edge down
00:48:22Because we've had a couple pop there and we don't want that and I'm happy. I'm happy to say that
00:48:31This is happening now at Honda Kawasaki
00:48:35All the places that have in-house departments if you go to Kawasaki
00:48:39They have a fab shop. They have multiple mills welders. They got parts every this is related to motocross
00:48:45It's happening KTM Roger Dacosta is a
00:48:49like
00:48:50Superhuman example of this in expression because that KTM racing there's Rogers mill
00:48:56He has his own mill and he uses it to make parts
00:48:58Like he actually is still using the mill like he's not just running the team
00:49:03Running the effort. Let's say he's he's in there
00:49:06Getting dirty and doing it and they've got they've got
00:49:10CNC porting machines KTMs race effort out. There's at their new headquarters. They built pure mobility and and all that
00:49:18you know many millions of dollars and it's it's a beautiful complex and it's you know, it's great and
00:49:24They're out there making chips and there's a porting and department and people building heads
00:49:29It's it's a thing of beauty and that's it's beautiful to see Harley Harley had in-house racing
00:49:35Foreman machinists people competent with the parts
00:49:39Then they sort of offshored it so to speak to Vance and Heinz a lot of a lot of it was just happening outside
00:49:44The building and now with baggers
00:49:47It's all those people inside the building just going and now
00:49:52Ring packs the ring pack that they used in the race motor is the ring pack
00:49:56They put in the 135 crate motor that they sell
00:49:59Hmm the intake
00:50:01They found a design for an intake manifold that they machined from billet and shipped it to like road Atlanta or wherever the hell the race
00:50:08Was and it made more power
00:50:11They sent that and said you're using this now on the production. Yeah
00:50:17Here's it's great. Yeah, it's great because
00:50:24Although
00:50:25The great majority of people who ride motorcycles ride them in a I
00:50:34Hesitate to say a pedestrian manner, but they ride them well within their design capabilities
00:50:40Because they are not professional riders and because they're on the street where there are no
00:50:45medics and
00:50:47Where there are people on their phone who have no clue that you exist
00:50:53But
00:50:55We want these motorcycles to be capable of
00:51:00Doing
00:51:01Everything that has been designed into them. So just having a bunch of parts that you put together and hope for the best
00:51:10this is
00:51:12This is where all of those
00:51:15Wonderful quality assurance systems that dr. Deming and others
00:51:20Developed during the war in which Harley Davidson became
00:51:25adept
00:51:26so adept at
00:51:28Employing that they consulted with other American manufacturers on just in time and various
00:51:35quality assurance schemes
00:51:40His motto dr. Deming's motto was an increase in quality is an increase in
00:51:47production
00:51:48because if you're rejecting
00:51:5030%
00:51:51For defects and you fix those defects
00:51:55Production is up 30%
00:51:58and
00:52:00so continuous improvement as
00:52:04a
00:52:05Manufacturing principle is the way a race team has to live all the time
00:52:11Right. It's crisis mode all the time. That's yes. That's what's good about it. Is it's not we we're not gonna have a bunch of meetings
00:52:17We're gonna we're gonna cut this and reweld it and see what happens or whatever. That is
00:52:22I want to talk about what you were saying about the all the riders
00:52:25They ride the street riders ride well within you know
00:52:27The safety margins of the product or whatever on the flip side of that talking to someone at Hinkley triumph during he Hinkley triumphs
00:52:36Early days and development and like we've tested these bikes and we you know
00:52:41We cut them loose into the American market and the guy who was running triumph in America at that time
00:52:47He said I I told him we we really got it. We got to test these things. We really really got to test these things and
00:52:55They said they did and then
00:52:59He said they could not believe what riders in the market could break like okay. Yeah, how'd they do that?
00:53:06and it's just that's what's
00:53:09Miraculous about and they're all fit like it's the triumphs are amazing. And you know, I'm I'm amazed at how
00:53:17great and reliable new motorcycles are
00:53:21Like just take pick any pick pick an r1m. Go buy a Yamaha r1m
00:53:28do the break-in change your oil get all that stuff done and
00:53:32Then turn the key on start it and let it idle and just let it idle as long as you want like a week
00:53:38Quick keep putting gas in it ride it to
00:53:41Chuck Walla ride it to Willow Springs ride it to Laguna Seca and
00:53:45And then just cut endless laps on the motorcycle until the tires are smoked and you got to change the tires change the tires
00:53:52Keep lubing the chain change the chain
00:53:55keep cutting laps and
00:53:58you can I
00:54:01Would love to just do that like every morning get up and ride laps at Laguna Seca all day
00:54:07Yeah, and how long until I get a failure I bet practically never I would break before the bike. Yeah
00:54:14Well, I talked with a Kawasaki DM years ago who said
00:54:19Well, you know
00:54:21Riders like to do burnouts. It's sort of the fashion and
00:54:27Said so we've made the clutches bigger and it made the failures more frequent
00:54:36How did that work well he said
00:54:39They quickly found out they could do more burnouts
00:54:42With the stronger clutch and so they did more and more
00:54:47So we've made the clutch bigger again, and we're crossing our fingers on this one
00:54:52but yes
00:54:54the
00:54:55Street rider is in
00:54:58Relation to the motorcycle like the enlisted man to the various technologies that are available to the armed services
00:55:05Which is why they try to
00:55:08Simplify things down to the point where for those who can read it says this end toward enemy
00:55:17and
00:55:19My middle son was in Afghanistan and they told him no you can't work on those mine rowers
00:55:26They can only be worked on by factory personnel. Well
00:55:30On the books we have six mine rowers, but there are no mine rowers available
00:55:36So he his officer said fix this for me
00:55:39Will you so he went and got a tractor and saw that one of the rowers could be nudged into the 90%
00:55:4690 degree position
00:55:48And it would click in the hydraulics were shot on
00:55:52So he was in the middle of doing that and some busybody came up and said I'm putting you on report
00:55:58Fortunately his officer arrived and said he's doing exactly what I ordered him to do
00:56:03Yeah, we we have a joke in the fire department about trying to make things firefighter proof it's the same
00:56:08Yeah, you know, we just boy you can break stuff any any fleet vehicle God
00:56:14Anyway, different story a couple things. Let's see. We talked about the crankshaft and having a built-up crankshaft. They
00:56:21And welding and all that that was that was cool. There's the cam gear situation. Oh, yeah each
00:56:29Valve has its own tappet and its own cam lobe
00:56:32so there are four cams each with a gear and
00:56:35That's why on a sports or an XR
00:56:39You will see two parallel push rods two parallel push rods and down at the bottom
00:56:45There are the gears. They're all meshed together and
00:56:52The exhaust cam on an XR on the
00:56:55The exhaust cam on an XR on the rear cylinder
00:57:01fails more often and
00:57:03It used to be that you could all these gears were made with
00:57:08standard clearance tight and loose and
00:57:12People would put them together to minimize the the amount of clicking
00:57:16because when when you're lifting a valve that's 280 pounds open and
00:57:23It passes over the nose
00:57:25Suddenly you were trying to compress the spring
00:57:29With the torque in the cam and now the spring is suddenly taken up all the clearance in the other direction click
00:57:37That's happening every revolution. Yeah of the camshaft
00:57:43that's a lot of fatigue events and
00:57:47Those gears would break but
00:57:52We have still competent gear making
00:57:56Companies in this country that could be solved that could be solved this same problem
00:58:02began to plague
00:58:04max Norton 500s in the
00:58:08Early 50s late 40s
00:58:11Crank pins would break
00:58:13well
00:58:15Norton's don't break crank pins now they do
00:58:18Because they had been a 6500 rpm engine now they were turning 7200
00:58:24So what the clever boys were doing was using a Jaguar plane bearing connecting rod
00:58:33making their own gigantic crank pin and
00:58:37The last time that a max Norton won
00:58:40the Isle of Man senior TT
00:58:44was
00:58:461961 when Mike Hilwood rode a
00:58:50Was it a Lacey
00:58:53It was a highly modified max and he was able to win because the MV that had been leading most of the race
00:59:01encountered sticking throttle
00:59:04So
00:59:07They went to plane bearings on next it's an interesting and thing that you say about
00:59:14The development of the max Norton, you know in in vintage racing now
00:59:20you're dealing with
00:59:23Max Norton's that are basically made from completely new parts. Yeah, and everything's improved and an
00:59:32actual
00:59:34Max Norton like a friend of mine his dad Tony Tony Murphy. His father-in-law is
00:59:40selling his
00:59:41very late banks and
00:59:43It's all original and like thinking to myself man
00:59:46I'd love to I'd love to go vintage race a max, you know with the in the 500 premier class and armor or whatever
00:59:53But it actually wouldn't be competitive because all the new bikes have been developed and so you're turning
00:59:599,000 right and you take that thing out and like I'd be you're doing parade laps. You know, you're not you're not competitive. Yeah
01:00:07Back to the XR I
01:00:11Think one of the most beautiful things about the XR is the intake and combustion chamber. Oh
01:00:18No question. What do you think? Tell me about that?
01:00:22well
01:00:24There are people who will tell you
01:00:28The the max or the
01:00:32XR combustion chamber is a dead copy of a 350 BSA Gold Star
01:00:38So I asked Pete Zylstra and he said
01:00:43No, certainly not and then he told me some of the history of how they developed it which included
01:00:51Persuading Dick O'Brien to give up on oil
01:00:55Mahogany as the material to make
01:00:58Airflow models and making it out of plexiglass. Oh, it'll be so expensive
01:01:04Somebody will come down from accounting to talk to us
01:01:08So they this I think it's in the museum. I think you can go see this thing
01:01:16and it has the port that that they ended up with and
01:01:20I believe that during the development of the
01:01:261971 the modified iron motor the one that Calvin Rayburn impressed the world with at the
01:01:35Transatlantic match races that year beat all these people who lived on those circuits
01:01:43With a
01:01:45engine made out of cast iron
01:01:47Just can't happen but in America buddy cast iron we love it it did happen and
01:01:54I think that
01:01:56Dick O'Brien
01:01:58had a
01:02:01Made a big leap of understanding because he understood and I think that Jerry Branch was probably
01:02:10part of the discussion and an important one because Jerry was working with
01:02:15Cylinder heads from every other motorcycle that existed at that time
01:02:19So he had lots of ideas in his head and he was energetic and a genius
01:02:25Energy a genius with a lot of actual information
01:02:30Yep
01:02:31and he
01:02:33managed to persuade
01:02:35Obie to
01:02:37accept the idea that a
01:02:40properly designed
01:02:42low
01:02:44Resistance intake port and a smaller valve
01:02:48would provide such high velocity in the mid-range that
01:02:53The mid-range would become much stronger by this simple mechanism
01:02:59High-speed airflow in the port can keep on charging into the cylinder
01:03:05After the piston reaches bottom dead center and even as it starts to come up to compress
01:03:12The fresh charge because there's a lot of momentum now people talk about
01:03:18Mean intake velocity and that means averaged over the whole time that the valve is open and they have figures like
01:03:27343 feet per second
01:03:28But the fact is the first half of the stroke the air is kind of going do you feel something happening?
01:03:35I think we have to go this way
01:03:39The inertia of the air
01:03:41resists being
01:03:43Accelerated and by the second half of the stroke the air is catching up and by bottom center
01:03:49It's going really fast and I mean up close to the speed of sound
01:03:55So it's no joke that it can keep on crowding in there
01:03:59And this is why when I asked Claudio Domenicalli who is now the big cheese at Ducati
01:04:07What about keeping the intake valves open longer after bottom center he said yes
01:04:14You can make all kinds of power that way, but it makes the power band
01:04:19impossible to use
01:04:22Well, there's a statement and so
01:04:28The XR
01:04:30Could be said to be a racing tractor because they paid attention to
01:04:35every part of the power band that was actually used on the racetrack and
01:04:41Made it better as much better as they possibly could and there were
01:04:47Some steps along the way I think the late
01:04:51Kenny Augustine
01:04:53Was called in to rework the exhaust port at least he came up with the flat floor
01:05:00Which you can trace back to
01:05:03Jocko Johnson in the in the late 50s
01:05:09But these people who work with airflow are they're all working with the same air
01:05:14So don't be surprised if they come up with similar solutions
01:05:18and they're all
01:05:20Go ahead. Well raising the floor of the port
01:05:24and
01:05:26Then raising the roof of the port
01:05:28And then raising the roof of the port take some of the angle out
01:05:33And as Kenny liked to say
01:05:35You can make air go fast
01:05:37And you can make air go around corners, but you can't do both at the same time
01:05:43so
01:05:44this is why
01:05:46exhaust ports pointing up
01:05:49Have appeared on engines like Ducati's Testastretta
01:05:53Usually however packaging. Oh the exhaust pipes have to come out of the cylinder head and
01:05:59Tucked down immediately just to allow room for the radiator and the front tire
01:06:04so
01:06:06Compromise
01:06:08That's necessary. You said everyone's
01:06:10Working with the same air. So it's no no surprise that they come up with the similar solutions
01:06:16Everyone's working with the same dirt
01:06:18Yeah, right and that's why
01:06:20That's why
01:06:22the FTR 750 torque curve is this
01:06:25Incredible like flat manageable thing. Yes. You've that's the only way you get off a corner
01:06:31You have in fact that the mile track lap record hasn't changed
01:06:37All that much since 1911
01:06:41I think dirt is a is a constant
01:06:44But
01:06:46They haven't found ways to fill it with some kind of glue like they see the
01:06:54Vhd
01:06:55A highly variable constant, you know the moisture and different tracks and gravel and all the things
01:07:00But yeah
01:07:00You only get so much and you only have so much to work with
01:07:04And that's true in moto gp. You only have so much traction to work with. It's just you have a lot more
01:07:09But you still need a manageable power band. You're still trying to
01:07:13Have the power and control to make the most of the traction for as long as you have it
01:07:18and
01:07:20You talk to experienced dirt track builders and they'll say
01:07:24somewhere
01:07:25between 90 and 100 horsepower
01:07:29With a good
01:07:30Power band is what you need
01:07:33There have been lots of much more powerful engines put into dirt tractors
01:07:39Engines making up to 125 horsepower and the the rider just
01:07:44Comes in shaking his head and says well
01:07:48I'd like
01:07:49I'd like to hook this thing up, but I can't figure out how
01:07:52Yeah, super trackers was a real interesting experiment around 99 2000
01:07:57In that era and they were running, you know, ducati
01:08:01v twins and tl1000 motors and
01:08:04just the various
01:08:06Manufacturers honda and and all that having v twins 90 degree v twins and desmo v twins
01:08:12well, they're hoping to go to
01:08:14an entirely production-based
01:08:17formula for american flat track
01:08:20and
01:08:23The argument is is that having one
01:08:27factory bike
01:08:29factory race engine
01:08:31Versus everybody's home-built even if it's a very high level home-built like
01:08:38Bill Werner's kawasaki's and what's been done with them since where it's a kawasaki in name only
01:08:50People would like to imagine having several brands that all finish
01:08:55very close
01:08:56in every race
01:08:58But the fearful thing the dangerous outcome is what I call the colex effect
01:09:04when they came out with
01:09:06moto 2
01:09:08Which is the next class?
01:09:10to moto gp where
01:09:13people arrive
01:09:14They win moto 2 and they're sort of and now and now
01:09:20um
01:09:23They decided moto 2 will will have stock engines so that will save everyone the expense of developing horsepower
01:09:31And it will unleash a torrent of chassis innovation
01:09:36And what it unleashed was colex
01:09:39Colex made a chassis that everyone liked and nobody uses anything else
01:09:44And triumph does the engine
01:09:47And that's that's what you get
01:09:49And this is this is always a danger in racing is that something will turn out to be
01:09:55Okay, you need one of these
01:09:57And it won't matter
01:10:00people have called yamaha people have called kawasaki and said
01:10:05Oh, please are you're coming to help us in dirt track, aren't you? It's american grassroots sport
01:10:11It will help you sell motorcycles and they're saying
01:10:15Nobody goes to these things anymore
01:10:17And they don't buy new motorcycles
01:10:22Don't answer the phone next time put it on the reject list and
01:10:28It goes like that
01:10:30They well if you're if you're in racing if you're in the racing department at any manufacturer yamaha is a good example because they they've had
01:10:38Highly enthusiastic people in the racing department and great technicians
01:10:43But the other pressure there is
01:10:46Is budgetary yeah
01:10:49and you see it in
01:10:51there isn't a
01:10:52Huge factory yamaha rig and we're not you know, we're not getting engines shipped over from japan that i'm aware of
01:10:59um, it's
01:11:00You know, it's a factory supported team. They're there
01:11:03but you know, they put they got a lot going on in supercross and and motocross and
01:11:10when they debuted the um
01:11:13T7, you know the 700 cc motor and a flat track frame
01:11:18We we went to him. We had a rider hayden gillam
01:11:22we were like, hey, let's let's race a flat track bike and do a media series and get hayden gillan and and
01:11:28When we talked to the folks yamaha i'm like we love that idea
01:11:33But we don't have the money to do it
01:11:35Yeah, we we have to focus on these
01:11:37Areas in racing and they were spending a lot of racing suzuki was spending a lot on racing and they
01:11:42kind of hit the reset button and
01:11:44and
01:11:46They have good racing programs that they're probably spending quite a bit less on so
01:11:51That's part of the challenge, of course
01:11:54Yes, but what never ends
01:11:56is people with ideas
01:11:58and
01:11:59And the desire to race whatever. Yeah, that's the media
01:12:04when the factories have
01:12:06Money to spend those people with ideas
01:12:09often find employment and at other times
01:12:13they
01:12:15Get home late and they find all the lights in their house are dark and they're thinking
01:12:20Damn, I thought I was getting home earlier than this
01:12:23Yeah, because they're at the shop
01:12:25Yeah trying to solve a problem. This is a good place to uh
01:12:30Say thanks for listening folks, but I want to get I want to tuck. I want to tuck one thing in
01:12:35And I think it was the metals podcast
01:12:38You said oh, I uh, I put a I put a set of pistons in my ex-wife's oven
01:12:45Yes, and somebody pulled that up. It's just haha ex-wife. Yes
01:12:49sure
01:12:51It was a good stuff. We appreciate your comments. We're super glad you're listening with us
01:12:56um, you know keep on listening keep on going in the comments because we are um, so uh,
01:13:01delighted that you're riding along with us in this and um
01:13:04We want to hear from you. We want to hear from you
01:13:07A lot of the topics that we have talked about the oval piston honda, uh, that's a previous podcast
01:13:12It's all come out of the comments. We're reading them. I try to get in there
01:13:17and say hey, howdy, and we appreciate it and uh
01:13:21Thanks for listening. We'll see you next week