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Originally Posted by KRTTXRTT
Back when I was racing I always wanted an XRTT and now that I am old...er (a lot!) I still do.
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You shouldn't get me started
Don't tell anyone but the XR road racer is probably one of the most fun things there is to ride, if you like v-twins. It's at the tail end of class C so it's not some ridiculous pile of Jap tinfoil that may as well be a refrigerator .. it still feels like a bike. And they are easy to ride.
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Back in about 1980 I watched Malcomb Tunstall ride a protoype Iron head version with two carbs (both 45mm Mikuni's!) and it was shocking to see what he could do on that old war horse.
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They are skinny and short and lean over easy but they are also stable so you don't need ABS and a gyroscope to ride them. They don't weigh 600 lbs. You can hop on and go and have the time of your life. They are the end of the Mike the Bike, John Surtees, Gary Nixon neat tucked-in style of riding. The only thing that might be as much fun would be a BSA or Triumph triple of the same period. Okay, a TZ-700 would be exciting but ... not the same
Want to see some people get pissed off ? Ducatis are bear squat by comparison. The 90* cylinder angle sucks, the wheelbase is too long, you can't get enough weight on the front wheel, the heads don't flow, in comparison to an HD they are crap
If HD really wanted the Sport Bike segment they didn't need Buell. All they had to do was streetify an XR road racer. There's no Ducati born that could keep up.
Yuppies .... sigh. I must be having a second childhood but haven't really paid much attention to motorcycles for a while. All of a sudden the place has been swamped with yuppies who know everything but everything they know is wrong. They
adore all this stuff that in 1970 you couldn't pay people to take. A friend's shop got one of the early Ducati dealerships - he was lucky to sell three or four bikes. And Harley - jeeze. If a magazine had an article about an H-D in it, you couldn't pick it up it was so hot from all the nasty words they used. Most people hated Harley.
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It still had the 35mm Ceriani yet used the later low boy frame
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When they were racing Class C they
always had the 35 mm Cerianis. That was all there was
The thing is, Cerianis came in different lengths. The road racers had the very shortest you could get, and sometimes they even cut the tubes shorter. (Easy to do on Cerianis , it's just a tube with some threads at the top and a snapring groove.) With that dropped steering head if you run the shortest Cerianis, pop the springs out and you will see the triple clamps almost touch the tops of the fork slider boots. They are as short as you can get. And we know what that means
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Jim told me they had cured the heating problem by the time that bike was built
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Yeah, right. My
They stuck two or three coolers on the oil going into the heads, they pumped as much oil as they could find through the heads, they put in external drains so the hot oil from the heads could go direct to the sump without boiling the rest of the engine, the iron XR's looked like a pre-war Vincent "plumber's nightmare" and they
still melted.
I fixed the problem. I ran alcohol. But you can't do that if you are serious. This was AFM Open GP in the days when everybody was just having a good time. If it had started winning then someone would have bitched but until then, it's "run what ya brung and have a good time." Everybody in the back was cheating and we all knew it. Chamber's Rickman Honda 750 had like 1200 cc's and nobody cared and he probably wasn't the worst offender.
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yet the alloy version became the focus and the rest is history...
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It was a time of big changes .... and the end of AMA popularity, if you want to know the truth. The AMA blew it bigtime. Gordon Jennings even wrote an article about this at the time, so it was not a surprise to people with brains.
It's kind of funny ... you see the same thing in human history time after time after time. Maybe there is no getting around it. Something becomes popular because it is very very cool. Then because it is popular, the hangers-on, the yuppies, the promoters, the leeches have to get in there and grab a big bite. Television ! Advertising money ! We'se gonna be stars ! And suddenly it is no longer cool or special or wonderful and there are no real people with character quirks and personalities* involved, it's just another
advertising campaign. And then of course since it's no longer any good it becomes not-popular so the hangers-on wander off to destroy something else and all you have are memories. The AMA in the mid-seventies was disgusting, worse than a two-bit crack whore. Ed Youngblood, bah.
* There was a national in the Midwest that got rained out. Everybody is there but no race. Springer is like, "Shit, I didn't come to sit here in the van" so he found a vacant warehouse nearby. Talks to everybody, they all take their pit bikes and sneak into the warehouse, everybody throws $5 into the pot and they hold their own national for a $150 purse. That's AMA dirt guys. Cale Yarborough, Tony Stewart ? Yup. Jeff Gordon, Jorge Lorenzo, Dani Pedroso ? What do you think ?
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I am building mine to be fairly accurate.
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Accurate as a fun street bike or accurate as a vintage racer ? Or accurate-looking as a fun thing to build and ride ? The three are not the same
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Currently I am thinking I will use Gremeca calipers on some iron rotors as they are allowed in the vintage class (availible in 1973 etc) likely on spoke wheels all though I keep looking at older mags with some lust.
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I suppose Morris Mags would be okay - at the time they were "mmmm, nice !" but today, I'd go with spoked wheels. And if you can find one, a Fontana. It is
so much nicer than a disk brake. If this is for fun, go with the drum brake. Honest. The most fun I ever had (on a bike) was with a Sprint road racer at Sears with Oldani brakes. You don't actually ride a Sprint : you sort of think, "Go left" and it does. Or, "Go right. Now stop on a dime. Okay, let's go again" and it does. With those Italian drum brakes you can feel the slightest little weed, bump, slimy spot, anything. They have so much feel and such low lever pressure that you will fall in love. If you're Calvin going for the win at a National maybe not so much but for a fun ride ? Fontana all the way. Or Ceriani. or Oldani.
To tell the truth, a Sprint road racer is probably the most fun you can have. They go fast enough but you always feel like you are in total control, unlike with a 77-inch Sportster motor
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I am still using the Cerianin road race fork too, as I think it will work with that low steering head (short = stiff - I tell my wife that!).
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The short Ceriani will be fine. You can't find the upper triple clamp anymore but you can modify a standard one to look the same.
Have to be careful what you tell the wife, they are likely to tell you "Can't beat cubic inches"
I just keep my mouth shut now, it's safer ....
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the greatest pavement rider ever (Mr Rayborn in my book) so it was hard to tell if they really worked that well or?
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I think they work great but me and them are both from a bygone age ... I don't think picking up the front wheel and accelerating into the nearest tree at 130 mph is so much fun. People nowadays like that. I thought duHamel was a dunce (the idiot crashed right in front of me in the pits once, what a turkey), but that's what people like now. So you just have to decide what
you like and do that and to hell with everybody else.
First off, you could make a fun street bike. A reasonably builtup Sportster engine would be fairly cheap and great fun on country roads.
You could build the lightest, most fun least-scary road racer and be very vintage by making it a flathead. You could do a 61 inch flatty that would go good and be a lot lighter and handle better than an overhead and be even more vintage than an overhead. And they weren't slow - the flatheads were doing 1:52's at Sears, which ain't slow. And close to 150 at Daytona, if I remember right.
You could do a Rayborn iron replica but too many breakdowns. I would not recommend that.
You could build something that would scare yourself and probably hurt you by basically putting a dragster Sportster motor into that frame. Run it on alcohol
This is most people's first inclination - we all want more power ! but I dunno ... at some point the fun is in the activity, not in messing your pants.
A real XR or XR-1000 is just too much money for the fun you'd get out of it. And either one would be too much work and money to keep running.
I think if I were going to race one I'd go with either a flathead or a fairly mild motor that's not going to give any trouble, but let me spend my time riding instead of doing valve jobs and replacing the oil pump.
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share the ride you had: which track and of what length was the ride?
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Sears Point and Ontario ... my sister swears we went to Willow Springs once but I don't remember it. Probably true though because she went on at great length about how she learned to slipstream tractor-trailers on that trip. Oops
Anyway, the XR is fun anywhere. It's just fun, period ... but it's maybe a little more fun accelerating off a turn. I did not like Ontario at all. The front straight and turn one was a thrill (off the highway at 150 into the driveway everybody says "don't touch the brakes until turn six, yeah
right !), the rest was a featureless mess. Riverside was sort of okay but still not great. (I didn't have the Harley XR running then but ran the Vincent in an XR dirt frame there so have a good comparison point.) Sears was great fun. I'm more of an accelerate-out kinda guy rather than a slam on the brakes and hope you don't crash kinda guy. And swoops. Swoopy is great on the hog.
Speaking of which, this is one of the more impressive things I've seen : Sears Point, the race Roberts won so convincingly. Turn 11 is a nasty right-hand turn. Not tight enough to be a hairpin, not wide enough to be a real turn, there's a spring underneath and the pavement is always all broken up, slow and just nasty. Nasty nasty nasty and this was when Sears was all run down, before they repaved it and made it sweet for the modern pretty-boys. (Remember that when you compare times over the years, too. Sears was in terrible condition in the seventies.) In practice Romero would come through ten (sweeping right-hander and slippery as snot) flat out on his triple, wait
way too late to brake for eleven, get on the brakes
way too hard, let the inertia throw him forward onto the tank, the back end would come loose and whip around out from under him, about halfway through spinning out he'd calmly sit back in the seat, get traction, grab a handful and blast out of eleven. There's a three foot high concrete wall on the outside of this turn, by the way. No one else did that, not even Mr Roberts. He must have done this a dozen times in practice but never in the race. I always wondered why.
Speaking of Mr Roberts, right past eleven there's a pretty good left-hand kink in the "front straight." during the first ten laps or so of the national, KR would come through there heeled over about 45* hanging off the bike on the left, missing the pit wall by an inch or so, front wheel about a foot in the air, banging off shifts. It was like, "WTF !!" That was the most impressive ride I've ever seen anywhere, any time. It just made your mouth fall open. National numbers watching on the back side of the track were saying, "You can't do that. It's impossible." I don't care for Yamaha very much ? but if you were to pick the world's greatest roadracer of all time, it would be hard not to choose Kenny Roberts. There would have been some exciting races if Calvin R hadn't died.
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I think they only made about 8 of them so it is hard to find people that have actual seat time.
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I bet there's a lot more than 8. Yuppy collectors always do talk that way to jack up the value of their stuff. My chassis came from a Junior who ran it for a year, and in the factory photos there were always at least six or eight riders on them. They aren't that exotic : just the dropped steering head and a shorter swingarm is all. You could make one from just the swingarm-pivot casting if you wanted. All the fiberglass is available. (Having Jim B do it though is a good idea. He's done it before and knows what he's doing and is a cool guy. Just don't let him talk you into going with the dirt track geometry
)
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Also, I will be specifying a 26 degree head angle. With modern tires I fear that 25 degrees might twist frame/fork up a bit more than I expect...
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You know what ? You can get too carried away with specs. I got too carried away with building stuff and never really got to ride it as much as I wanted (started working for myself, that was the end of fun). A stock XR frame to roadrace specs, a decent
reliable Sporty motor of whatever configuration you want, and go have fun. Don't let yourself get carried away with the latest trickest this that or the other thing (electronic ignition tho - do NOT use the F-M magneto, UGH !) and every lap you spend riding instead of fixing will be your reward.
You'll have a great time. Promise ! They are a great bike.
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