Sunday, June 15, 2008

Home made slider

As I may have previously posted, there are a few Ducati MH900E parts that come up with the dreaded "NLA" tag on the parts microfiche. One of those is an 11 dollar part, but one that is critical to the machine. The upper chain slider. The lower one was easy to find, and I immediately bolted it to the bike when I got it months ago from Wildwood. I soon found that when I mounted the chain, the upper part of the newly-coated swingarm would get sawn through in short order. So obviously, Ducati put the slider in place for a reason. I first tried lexan, but the curve of the swingarm (in 3 different axis) made that only a temporary solution. I would need a proper one in nylon.

The good thing is, I was able to acquire a hunk of scrap nylon block, and utilizing the bandsaw, the drill press, an angle grinder, and a knife, I was able to carve out what you see here. Unfortunately the whiteness of it all sticks out a bit, but over time, some chain lube and road grime will hopefully color it a less contrasting color. It looks to be sorted! Big ups to PB member "Uschi" who sent me some pics of a stock upper slider to go by. Danke!

Monday, June 9, 2008

A tale of two headers

Eyeball (Hi-Ball) engineering strikes again. Here is a pic of the two modified PS100o headers Dad and I tacked together to creat my very unique exhaust treatment. Someday I might plump for a real custom set, with a single pipe and racy bends, but for now, this will work. They were tig-welded by the guys at Cycleboys, and I have put a coat of cheap hi-temp paint on them. The final step will be wrapping them in header wrap (black, again) to keep some heat off the rear shock, and perhaps my right boot.

Anyhoo, with a multi-cyclinder bike, there seems to be several ways to plumb out spent exhaust gasses -- a 4 banger might have a 4-2-2, a 4-2-1, and a 4-1; a triple might have a 3-1, or even a 3-collector-3 for style points (think new triumph speed triple); twins can be a few different configurations as well. My EX 500 was a 2-2, with a crossover under the engine; the Muzzy race pipe was a 2-1; stock Ducatis are primarily 2-2, with a bizarre, restrictive-looking X-piece underneath the rear of the engine. Ducati superbikes sacrificed some power for the sake of style and less drag with their then-radical underseat exhaust. Harleys (don't laugh) are one of the few large-displacement twins with separate headers per cylinder, with no crossover. They seem to make it work by focusing on keeping the header length the same, or as close to it as possible. Easy on a 60 degree cruiser with the turning radius of the Titanic; less so with a sportbike with a 90 degree L-twin. The route to the rear of the bike is far shorter with the rear cylinder.

My eyeball engineering has come up with this:

  • now modified, the header diameter is the same for both cylinders

  • the foward cylinder header is now 5.5" longer than the rear (before it was 9+" longer)

  • guesstimation states that the two bends in the shorter rear header is equivalent to adding length the the rear header... theoretically bringing the total length of each closer to the same
Fact? No clue. Before my ears started to bleed, the thing would at least idle with the straight-through pipes. Eagerly awaiting the parts to finish the cherry bomb specials (my cans) and the prefabricated ones I purchased. They are seen below on the original owners' SC1000.

Saturday, June 7, 2008

Took some more pics

These are mainly for the watchers on the Performance Bikes forum, some of whom requested some detail shots of the swingarm. It looks as if I will have to custom-make an upper chain slider for the swingarm, as there are none available.

The current sprocket installed is a 40 tooth jobbie. A bit short, (stock was 38), but it should be fun around town, using the Ducati tourque.

The lower exhaust canister mount is bolted to the spacer plate behind the rearset plate. The mounting holes are relieved so the heads of the bolts do not contact with the rearset plate.

I finished up the Suzuki 500 GP model awhile ago. I have been saving a "Fastdates 2001" calendar since December of that year. It was given to me by Scotty at Transcanada, and I kept it as it has this picture, as well as one of Garry McCoy from that year.

My plan was to always create something like this, with the model mounted to the action shot backdrop. I might use a sort of display box from a hobby store for the Red Bull YZR500... but I like this. Only 7 years in the making!

More Waiting

I've ordered the stuff I need to properly complete the exhaust system. Perforated tubing, as well as black header wrap, stainless steel zip ties, and pipe wrap paint are all on the way here. Not sure if I'll be able to do much prior to Kate and I leaving for the UK. I did spray the headers with hi-temp paint, and they have been hanging in the garage for a week. Should be plenty cured by the time the other stuff comes in. I also snagged a second set of exhaust cans, already shortened, from someone on the forum. If you haven't checked out that site, you should take a peek.

Sunday, June 1, 2008


Got the headers back from Cycleboyz and painted. Should work well, still wondering if I shouldn't wrap them in header wrap. They are actually stainless steel, but painted black... my question is, why go to the trouble of making an exhaust system in stainless, and then go and paint it? Either way, the tig welds look great, they patched the hole from the crossover pipe, and everything fits.
Since I was going to make a set of shorties anyway, in the interim, I hacked about 5" off the end of each of the exhaust stacks. While they looked 100 times better, what resulted was a straight-through type set-up, so when I fired up the bike, it was obscenely loud. Good news is, the bike still runs after a year dormant. Bad news is, the exhausts still need more work. This will involved some perforated tubes and nutserts (on order), and another trip to Cycleboys to tig weld the assembly back together again. The resulting cans will also be much lighter, and should have a more "rorty" exhaust note.
Wilson came over yesterday, and we chatted and I was able to weld a tab back on his TZ250 expansion chamber. His indication is that Gimli as a track is on the mend -- the turn 8-9 combo is being modified properly, and might even end up as a safer turn. I can't forsee me making it to the track before September this year... the trip in July and the resulting financial crunch will put a damper on my trackday excursions. It would be a good opportunity to "test" the bike before putting it on the street. I should probably sit down and put together chapter 3 of the Ducati build chronicles for Desmotimes -- see for a great website, forum, and club. If you are reading this, you should join!
Switched around some banjo bolts yesterday as well, and now have all the hydraulics bled and sorted -- the clutch, front and rear brake systems are all operational and ready to go. Another 20 zip ties, and all of the electronics and wiring is out of the way, including the front wheel speed sensor for the speedo. Just the pipes and a place to put the plate, and it should be able to hit the road!