New project: XS1100 endurance racer

[Mathh]

Well…. That new RC Engineering 4-1 that I first wanted to use gave me lots of grey hair in 2009 but the 4-1 Supertrapp collector that I cut up did the same because I could not get a decent connection with the collector afterwards and I could not swap the oil filter. So I gave it another try but as a 4-2-1. That worked better, I got them symmetrical looking from the front but it still came very close to the front frame tubes and the pipes were not symmetrical from the side up front and at the bottom due to its previous design which had pipes #1 and #4 on top of pipes #3 and #4 at collector level.





We could heat them in order to bend them a little bit but not that much. Luckily my friend Mario who is a professional TIG welder came to the rescue. First thing he told me was that we had to cut of the flanges at the cylinder AGAIN in order to gain some length and change some important angles. After that he told me to make 4 new stainless exhaust manifolds for rigidity to fit to the exhaust ports. That took some machining on the lathe, welding them to a slightly thicker piece of pipe and machining that again to get a clean look and correct thickness..





After mounting the flanges in place it was now very obvious that the necessary angle for the downpipe after the flange will be quite a compromise between clearing the frame and efficient exhaust design.

[Mathh]

Beginning at cylinder 1 we started trial fitting the downpipe with tape in order to see where we had to cut to get symmetry from all sides but ignoring the last bend at the bottom. That would be corrected by heating when all downpipes were in their final place. Then we did number 4, 2 and 3. We tried every downpipe to every cylinder in order to look for the best result...





It took a couple of days to get all four at an optimum angle and symmetrical from all sides.

[Mathh]

We now started work on getting the ends into two 2-1 manifolds. We found those on Ebay UK: they were for a stainless MINI Cooper DIY exhaust system that shared the exact inner and outer pipe dimension.



After making sure that all downpipes cleared the frame and hung symmetrically we started cutting the flanges and downpipes to the necessary angles to stay clear of the frame. After that we tack welded them in place.
With the downpipes in their correct place It was obvious why our first attempts with the down pipes failed miserably, look at the angles we needed to make to get the perfect result:

[Mathh]

As expected we had to heat two downpipes (2 and 3) to get the correct angle upwards and sideways. So we inserted heat ….





Bending was done with a piece of pipe that fitted exactly over the exhaust pipe (barely visible in the picture). Very careful not to wrinkle the bend. Also both manifolds needed cutting, heating and welding in order to get it perfect.
And that is what it looked like: perfect… Time for welding the down pipes...
Mario is a perfectionist so insisted on a clean surface after the welding. Lucky for me.

[Mathh]

The result looks great!



The idea of the following link pipes going directly to the rear and from there to the mufflers (on the right side) would mean that there would be a big difference in length in the left and right pipes. Instead we went for a couple of different bends followed by two equal lengths of pipe and into another 2-1 manifold and going to the two mufflers. Both mufflers will be on the right side. We wanted to stay as high as possible with the exhaust so we had to take away some corner bits of the oil pan to get a clean exit:



As I never throw away pieces of pipe or bends we had everything to work with using lots of tape.

[Mathh]

The end pipe has to come out below and behind the right footrest to avoid ground clearance trouble because of the chain on the left side. All downpipes will be held by stainless springs connecting to the 2-1 manifolds and the clamping rings holding the flanges in place. That will be done in the end.
After wasting a lot of tape, fiddling, cutting and welding pieces of straight pipe, bends and fabricating that 2-1 collector we finally found a good looking setup.

[Mathh]

And Mario could start welding everything we had put together so far..

[Mathh]

While he was doing that I dismantled the two open shorty mufflers and started to cut them up in order to get them together at the same starting point behind the foot rest. . The inside diameter of both mufflers will be same as the diameter of the stock bikes.



As soon as Mario was ready with the collector he started welding the mufflers together and finally he welded a tiny dot on top of each downpipe to keep the clamping rings in place.





At this moment we still need another link pipe with bend(s) to the mufflers. That will be done later as the bike is coming apart any time now.
Here is the idea for the position of the mufflers. I chose double mufflers (that makes it into a 4-2-1-2) for less noise: 2 mufflers mean half the exhaust gas speed of one 4-1 muffler (with the same diameter of course) and that means less noise.

[Mathh]

Now we still have to figure out how to connect the final link pipe to both muffler internals… that will be a 3D combination of a bend from the last interlink and a compact 1-2 to the mufflers side. Also we have to fabricate some decibel eaters that fit snugly inside the mufflers and some mounts to secure the rear of the exhaust to the frame (rubber mount) and the mufflers to the frame. Those 2 mounts will be done before the frame will be painted.



A while ago I started with a mini wiring diagram for this bike alone. I’m not a specialist but when I understand it, it will suffice hahaha. Still have to change a couple of things like tach and speedo unit and other things. I bet this will make life a lot easier when the wiring starts.

[Mathh]

And this is how the bike looks at the moment, 14 years after the build started. Sorry for that hahaha. Ready to be taken apart further and getting prepped for paint.







I have to start thinking about colours and design now!
Will be continued 😉

[Mathh]

The plan was to check the spare engine that was used for building the frame. That was the original engine that came out of my turbo bike after a crash in the 80’s. But I forgot the cases were damaged on the ignition side and the repair did not look that good so I decided to swap it with the engine still fitted in the turbo bike.
I have been selling that bike in parts since a couple of years as I no longer have time to rebuild it again. After 42 turbocharged years and 250.000 kms it was time to say goodbye to the bike that took me around most of Europe in the eighties and then some. Two years ago I already sold the 36 liter widened fuel tank and the YZF750 single seat and last year I sold the complete turbokit from that bike together with the Electromotiv fuel Injection with integrated ignition, intercooler plus the cylinder with pistons in one go.
So I put the turbo engine on a workbench next to the spare engine to check and compare. The best engine will find its home in the racer and the remaining one will be sold together with the ex-turbo as a project for someone daring enough..





Well, it turns out that both engines have great looking clutches and gearboxes although the gears from the turbo bike were coloured blue from the heat. As I still have a spare gearbox in case of emergency I decided to leave everything in place to save time and work and after installing a complete kickstarter assembly in the engine destined for the racer I closed the cases again. Pistons and cylinders from the spare engine were cleaned and measured and are ok.

[Mathh]

The spare cylinder above was alsomeasured ok and cleaned up great!

Then it was time for the cylinder heads
Well... there were some problems. Numbers 3 and 4 failed in the leak test:



not dramatically but enough to not use them but luckily the ex-turbo cylinder head was in better shape.



Only one of the shim buckets was frozen in its place from standing and it only decided to let go when I heated it up with a torch. Sadly I made a scratch using a pair of pliers to get it out so I have to clean that up first. The turbo cams also were a lot darker because of heat and showed wear on the bearing surfaces so these have to go as well. The slotted cam sprockets however were looking good but for the racer I will stick with non-modified ones.



And luckily there is that third cylinder head lying around so we will be measuring that one up as well.



I hope to finish that next week.
Anybody interested to read about the turbo bike, here is the topic: https://xs11.club/forum/idle-talk-fo...s-super-modded

[Mathh]

I finished working on the fiberglass seat and front mudguard (pics will come later). I am also trying to design a new paint job for the bike so I made a zillion drawings / photoshops and so on. it should look like a Yamaha racer in the 79's/80's but not 1 on 1 and with some more adventurous colors. So no factory colors with the black and white speed blocks (some pics will come later).
I am also looking for a color to put on my frame. I want my frame to look like it has been nickel- or chrome plated or even looking like an aluminum frame. So the last months I have been testing dozens of spray cans in all variations I could find. Nothing even came close. Real chroming or nickel plating is ridiculously expensive over here and waiting lists now reach the second half of next year. All other techniques I ever heard of ... same story or even more dramatic results. So my question is: Are there techniques / paints available on your side of the pond that maybe come close to what I am looking for?

[LAB3]

As to the frame you could clean it up and polish it really good then seal it with a clear coat paint.

[DiverRay]

I've used a metalic spray paint that did well for an indoor project. Not sure how it would do on a bike frame, though. How long a wait to powder coat the frame? you can get an aluminum look with that.