So I finally got time to mess around a bit and I'm close-- but it's a complicated process.
I chose to have a spare clutch disc relined in kevlar from H&R clutch, grooved as per their recommendation. Had it back within a week and the clutch material seems to be holding. I went for a clutch made to be used in oil, rather than an "oil resistant" clutch simply because oil contamination isn't a risk, it's the point-- I wanted to be sure to have the best shot at this going into it I can. (Plus the Seibenrock always seems to be out of stock)
Speaking of oil: I went with 10W-40 Mobil diesel oil for the intermediate housing. The recommendation of H&R was automatic transmission fluid but in hopes of minimizing engine and transmission contamination if there is any fluid transfer I went with the diesel for compatibility (I go one engine oil change on diesel at the beginning of each winter anyways just because the "added detergents" make me feel good, superstitions aside...)
So what I hadn't counted on was the sheer violence and air expansion inside the new intermediate housing environment. The first attempt showed an almost immediate leak around the plastic "padding" (as BMW calls it) at the top of the transmission mating surface just next to the starter. It wasn't super surprising, considering I hadn't sealed that piece in there all the way but it was enough to allow me to test the clutch on the road.
After removing the transmission/swingarm/final drive/wheel as one unit (with a sledgehammer to break the sealant...) I whipped up an "air release fitting" as I call it on the lathe at school:
Full res:
http://i.imgur.com/LON3OXY.jpg
It's not perfect, but I'm not a machinist-- and yes it came out of that 2" aluminum, it's what I had on hand
after making a modified fixed swingarm pivot pin... :falldown:
So the nipple is sized so that a 1/4" ID vinyl tube would fit snugly over it (about .3") and there is a 3mm hole drilled from the nipple almost to the bottom of the piece. The bit at the end was ground off so that it would fit into the plastic "padding" from earlier and the threads were approximately 1/4x20 (no metric lathes at school). I did this freehand so never drew any official drawings for it. After threading it all the way through the plastic padding I used a dremel to open a small slot in the threaded portion of the shaft which would be inside the intermediate housing and act as the air release path through the 3mm internal hole (and of course I forgot to take pictures of this too...). I faced the slot to the rear of the bike to hopefully keep as much oil out of this new air release as possible and attached my hose:
Full res:
http://i.imgur.com/us2r4vC.jpg
Ignition coils on left, starter body on rightWell, air gets out. But so does oil-- so much so that it left a nice trail around the neighborhood. I've thought about trying to shield the air release port from oil on the inside or possibly running the transmission without its input shaft seal to allow the intermediate housing to vent through the transmission, but they're only ideas and I'm kinda out of time on this project. I'll be reverting back to the dry setup next weekend until I get another chance at working on this.
Unless you guys have any ideas, please share!
