New project: XS1100 endurance racer

[Shacknasty]

Now I want to know how it all turned out. Is the bike finished? Did Mathh ever race it? Did the fifth gear bushing rear it's ugly little head at 140 mph?

[dixiethedog]

I joined the forum after spotting this bike some how by accident! The build looks absolutely fantastic and i cant wait to see more. Keep up the good work.

I could probably write a thousand words saying how great the bike looks and complimenting your skills,but instead i'll write one word that says it all for me,and that word is;
WOW!

[WMarshy]

Thought you might like this bike...

http://www.motorcyclespecs.co.za/model/Custom%20Bikes/jesse_rooke_ktm_cafe_racer.htm

[Yamanatic]

Hey mathh,

I was looking through your photo's and text, amd know you are not the occasional Sunday racer, that is why I brought the issue up as mine was slightly turned up from stock specs too, excluding your hand built chassis, 21st century technology and more generous budget (I was just a lowly mechanic at a YamaDealer when doing the SE region). Much of my feedback on the gearbox came from Bud Parker (the factory rep at the time), and since there was no internet, correspondence was by mail and phone.

It is amazing how much more interest and participation there is in the road racing community outside the USA; most of the dedicated knee-draggers, in our age group especially, are either from European countries or Australia; Belgium & Ireland seem to stand out in the community. If ever I were to relocate...

Anyway, mine broke coming off the tri-oval at Daytona during the Paul Revere 250 night endurance race on lap 56, about 100 yards past the infield entry. I remember thinking: "That burble didn't feel like it's out of ga...," and that was when the excitement began. It took all the way to the entrance to turn one to get stopped, and luckily directional inertia won. Daytona eats machinery, as you probably know all to well; if it's gonna blow, that's the track that will do (did) it, and for the second time.

Now I got one of these:

Archaic, but THAT is a gearbox for leanin' on. All roller and needle bearing with a dedicated pressure fed oil supply, and gear teeth the size of bullets. Digging around in there for a while can make one wonder about production bike engineering.

Keep up the good work, and when you get to the motor I am sure the same attention to detail will provide you with an extremely reliable machine. From the primary chain up, there is no stronger 4-banger outside of an automotive chassis. I particularly like the power delivery easing that much bike around turns; it is predictable and forgiving. Good luck!

Cheers,
Warren

[Mathh]

Interesting to hear and I will surely have a look at it as soon as the engine comes apart (still on the "to do" list) but I have to be honest: I have been thrashing XS1100's since 1978 and I have never encountered this problem, I haven't even heard of the problem, ever. My first XS did approx 85000 miles within one year : most of it on the autobahn wringing its neck at absolute top speed, my second XS did only a bit less miles within two years but also at very high speeds. My turbo has been thrashed hard for approx 120.000 miles and shows almost no wear. The factory endurance kit, as used in the Dior XS, used the stock gearbox as did Mel Pitman with his Aussie endurance racers and my friend Baloo with the yellow endurance racer (the only engine he blew up was due to a broken hyvo chain).
But I am never too old to learn, so I'll do some asking around on the Euro forums.
Anyone on this forum heard of this problem?

[Yamanatic]

I don't remember the bearing number, as it was about 28 years ago I did the fix. The modern bearing supply houses can come up with most anything from their 'stock.' I used the transmission shaft diameter as the crucial measurement, and had the gear I.D. machined to remove the brass bushing to tolerance fit the new outer race as it was necessary (for my approach) to locate the cage. The bearing looked like a miniature version of the R1 swingarm needle brg, with only an outer race and no inner.

The bearing was very economical, and machining charges were in the 1/2 hour range for labor. There was no need to re-harden the gear or shaft as no heat was used in the process. The big cost was buying another engine to bolt my slightly tricked-up top end to :-0 You may have a better way of engineering a fix; what I did just seemed to be the path of least resistance. I have logged about 20,000 miles of abuse since the fix (all with the turbo installed), and have not had it apart since buttoning it up way back then.

[WMarshy]

....BTW, it has a needle bearing supporting 5th gear now!

Any chance you remember what the bearing stock number is? Did you have to do any machining to get it in there?

[Yamanatic]

Lots to look through, and sorry if I missed this bit of info if already mentioned:

XS1100's have an inherent (and dangerous) weak spot in the transmission. 5th gear runs on a bushing rather than a roller bearing, and has been known to weld itself to the shaft. This happened to me during an endurance race; one slight burble, and less than a second later the gearbox locked solid. I was WFO showing about 140mph on the speedo when this happened, and nothing to do but ride (or crash) it out. Pulling in the clutch does nothing as the gearbox is coupled directly to the rear wheel.

I had no idea it was the gearbox and not the motor, and the rear wheel started to hop about the same time I grabbed the clutch expecting to just coast to a stop. The hopping just kept getting worse and started throwing the bike all over the track. I had not fallen down yet, and decided at this time to just ride it out instead of grabbing front brake and having the back end pass the front.

I was fortunate to be on the widest part of the track, and managed to not hit any barriers while skidding to a stop. It was sort of like throwing a steel bar through the back wheel at 140; not recommended. I was fortunate to have this happen on a straightaway, and everything began in a straight line. A corner or crown on the track would have earned me an instant trip to the hospital. Catastrophic failures at these speeds are enough to make one rethink racing altogether.

The engine was trashed as the cases fractured, the trans shaft twisted about 1/4 turn, and teeth were knocked off several gears. Unfortunately 5th gear did not shatter - that's one tough gear. I did run out of track at the end of the slide, and was let down gently somewhere below 50mph; whew...

After doing some post-failure investigating, I found that other XS11 owners had similar failures with mixed results. at least 2 instances were reported by Autobahn riders, and several racers had partial failures of the bushing. I retired my 11 from track racing, and rebuilt it with the Turbo for racing of the 1/4 mile variety. The avatar is that particular bike today; I have owned it 31 years now and it still reminds me of the ride of my life everytime I see numbers in the 130+ range. BTW, it has a needle bearing supporting 5th gear now!

[Mathh]

it's been a while

It's been a while, sorry for that. 3 weeks ago I started in my new fulltime job and I have been abroad constantly and time will be very scarce for the next 3 months.
A guy I know has all the spares for the dutch Z1300 club, so I could try the Canadian (16ltrs), the US (20 ltrs) and the euro version (27 ltrs) of the 1300 fuel tank. My first contact for finding the rare fairing told me it would be impossible as the builder was ill and it was unsure if he could ever build it. So I ordered some RCB1000 look-a-like fairings and seat in France with the help of our mutual friend Baloo from Baloo racing (he has the yellow xs endurance racer). Last saturday I received those.
The canadian tank was super flat and looked silly, so no pics there. First pic shows the US tank with the first fairing fitted with holes for the lights, second one shows the euro fuel tank. Looks way better imo.





The seat is a lot higher than the US tank and it just doesn't look right, although it follows the frame lines better (bit smaller) than the euro tank.
So the decision has been made: I'll definitely go on with the euro version tank.
Third pic shows the euro tank in combo with the second version (no holes for the lights).





I mounted the fairing higher than normal and at first instance it looks odd because of the very low headstock. That's because I want to sit as straight as possible instead of leaning forward, better for me back... Maybe it can still be lowered a tiny bit.
I will also add the oil cooler opening to the bottom of the final fairing (don't know which one yet) so the front of the fairing will get bigger and lower, making the hole between the fairing and the front fender smaller.



The rear end of the fairing pointing upwards now will be changed downward later..

[MeatTooth]

Wow that is sexy! I can't wait to see this one finished! You have got to submit this bike to some publications and share it with the world when you are done.

[Mathh]

well, I must admit it has been a while but .... busy, busy, busy. everybody overhere knows how that works,

You cannot yet see it on the pics but i removed the shock mounts and have been trying new versions, 3 different ones until now, still not satisfied..
I emailed with Fournales in France and they supplied me with a user manual but they also told me that the exact pressure for my project can only be obtained by experimenting.
I now put in 10 bar of air pressure (150psi) and it is not enough so now I am looking for a handpump used on mountainbike shocks that can handle 30 bar (450psi).
Because the engine moved over the frame tubes I did some welding to give them an extra mm of thickness, than added some holes with M8 thread and now I can secure the engine.



My friend Tom from the UK delivered my correct Talon sprocket (40T/530) on my doorstep, which I installed and then i shortened the chain. As soon as Fournales the shock has the correct pressure I can lower the frame to give it weight and weld the shock mounts on the swingarm and align the wheels



In the mean time I tried heaps of fuel tanks in combination with the desired seat, to look for a styling direction but nothing that i liked. And yes, i even tried the XS1100 fuel tank. then I ripped of the tank of my Z1300 dfi and I must admit it looks very, very period and cool! Maybe a bit too big, lower the front part, make the rear a bit less wide, but I might get used to it. I am now considering to buy an old tank and cut that one up and when I have the final shape I will make a new monocoque in aluminum.

[3Phase]

Nice work benches! I like the one you made using the truck jack because I already have a jack similar to the Rassant in your pictures.

[Mathh]

hydraulic workbench

Hi Exquized1, hope this helps!

I made some pics this week, but please understand that I am not a workbench builder by profession. So there will no doubt be easier, cheaper and better solutions than mine.
First of all I wanted my bench to be as stable as possible. For that you have to consider several things: start with a big footprint, as big as possible. Make sure the bench does not wobble when loaded: put all hinges as far as possible on the outsides. And last but not least: use a hydraulic jack as big as possible. The best solution is a jack designed for trucks.



When putting the jack in the middle of the bench, the pumping handle can still be reached and used from the outer side. However these things are very expensive, so in this case I chose a car type jack with a large lifting capacity (3 metric tons).



That way you can move it up with only little pumping action. These jacks also reach higher working levels than the smaller ones. Only downside of this system is that the pumping side of the bench rises sooner than the other side (this side only follows).
I wanted to use this bench for restoring classic bikes with as much storing room for parts as possible. So long term projects. Therefore it is supplied with some mounting points on the front to slide in an extension if needed.



I also always combine my benches with an electrical cable winch mounted on the ceiling. This way it is always possible to secure the bike or engine and frame separately in several ways.



As I wanted the bench BIG so I went for 40x40x2 mm square tubing. The frame on the floor is 600mm wide and 2100mm long. Working space is 690mm wide and 2200mm long (3mm thick). Remember this is big, most tables are much smaller. The sides are bent upwards 20mm to keep parts from falling down. Lots of hooks are welded all around the underside of the upper deck in order to strap things down.



Total height when fully up is 88cm, higher than most benches. On the jack end I welded a stop to lock a wheel up to 190mm wide and 19” high comfortably with a ratchet strap. I think this is a save way to prevent a bike from falling down the platform when the jack comes down in a hurry by accident.



First we stripped the hydraulic lift from all unnecessary parts as wheels, swiveling top and some strips. Than we made the outer perimeter of the bottom frame and decided were to put the jack which we welded securely to the frame. Make sure that the operating handle sticks out behind the workbench.







In order to get the hydraulic lift working in correspondence with the arms you must make sure the pivot points of the jack and the bottom of the arms line up exactly. If not it will block at a some point during lifting. Same with the upper of the arms and the top of the jack when in upright position. Be sure everything moves freely before you start any final welding. I added some grease nipples in the pivot points as well (out of harms way).







Because it is heavy I welded the wheels from the jack to the front of the bench. That makes it a lot easier to move around.



Last thing to do is drill some holes to prevent the bench from lowering due to hydraulic failure. Still have to do that on this one… I made some axles on the lathe to shove in these holes and block everything.



Good luck!

[Rick]

lol , now i know why u didnt get to germany , uve been busy here all along , catch u soon math

[Mathh]

hi exquized1, I will post some extra pics in a couple of days. I made it without any real plans, but it is relatively straightforward ...
@Roccet: not sure what you mean?