So there were a couple things I was hoping to do away with: the one way clutch (because it could potentially slip on the shaft) and the conical spring (no aftermarket replacements, also, I can't imagine it was a good design as they phased it out the next year).
So here's the bike, just about ready to take the side cover off. Exhaust removed, forward controls removed, piece of the frame removed, cross member removed. Yay!
So after careful measurements the outer clutch basket was almost identical with the exception of the big gear at the bottom of it, slightly taller on the '86, so I decided to keep it. Basket depth and overall height was the same so I wasn't too worried. Notice the nice spot for the 5 springs.
It didn't quite go as smoothly as I had hoped, but I didn't get any pics of the process. The shaft coming out of the transmission must be a little shorter on the '87, so I ended up having to put in a spacer for the nut to hold the inner clutch to the transmission shaft (I made it from the one on the '86 with an angle grinder and drill press). The longer shaft from the tranny also meant that the clutch didn't compress enough to engage the disks. To fix this I experimented with different shim arrangements until I got one of the inner metal disks and used it to space it out a little.
Here you can see the super conical spring on the old clutch.
So anyway, back to the new clutch. The addition of the clutch disk as a shim caused the clutch to stick out from the bike further and interfere with the clutch cover. Aftermaking a spacer from a part of the old clutch going back wasn't an option, not that I would have anyway, so I figured a spacer would be the easiest way to solve this. A few quick measurements on the bike and I was off to the store to buy some 1/4" 6061 aluminum plate.
After talking to Roy on the phone he suggested gluing the gasket to the plate, which was much better than my idea of tracing or marking compound on the cover. Anyway, I figured I could probably pull it off and not have to get the glued on gasket off by laying the gasket on and using it as a paint mask.
And it worked pretty well. Just need to cut off the areas with paint. I was thinking it would be cool to have a milling machine/water jet that could remove areas with a certain color paint or marker on them, then you could fab up parts without having to draw them up in a cad program for quick one off projects like this.
Here we go ready to cut some tests. I put the hole in the middle in case I made a big gnarly mess for my test cut and didn't want to mess up the contact surface.
Test cut with the jig saw went well, but it didn't turn well so I drilled a bunch of relief holes to make it easier. The inner radius was still too tight for the jig saw so but they helped with using the scroll saw with a wood cutting blade.
Jenny made me get a band saw for this project so I used it to cut away the exposed side while it was still heavily supported.
I finished up the inside with the scroll saw that I've had since around 12 years old. Still works like a champ :-).
I kept a candle around and would apply the wax to the blade to reduce the friction and help it pull the metal particles out of the cutting area. I read online that beeswax would have been better but this worked pretty well. That's what most of the crud on the cut out area is.
And another nice clean cut to finish it up from the bandsaw. This was my first time using a band saw, so I was a little nervous before I got started. I need to do a little more tuning on the saw to get it to stop wobbling (it's not too bad, just a little), but the band runs true on the belts and everything was nice and quiet and seemed to cut just fine. I also used wax on this while cutting.
I left a bit of a mess from the cuts and didn't want it to look out of place on the bike, also needed to remove any hanging bits. I started off with some 80 grit, worked up to 220 then used a scotch brite belt to finish it off. I didn't worry as much about the inside, mostly just needed to make sure no hanging bits of metal would come off and make sure that the inside of the bolted areas wouldn't contact the spinning clutch.
Looks pretty close, this thing would get pretty hot while sanding so I had to take a lot of breaks.
And now we're ready to roll. Outside looks good, inside looks good. Seems to fit properly.
Here it is giving me that extra space I need and then some. The blue crap is RTV, the red crap is some grease on the paper gasket (that I cleaned the paint off of). I figured that if I pulled it apart I would leave the spacer and the cover connected via RTV, and the grease should keep the paper gasket from adhering to the faces for a while.
As for the test ride? Woohoo! I don't think I realized how much and how often it was slipping until it was fixed. Every time I'd drop into a new gear it would slip a little as I released the clutch, now it's nice and solid. The handle is a little tougher to pull, but I guess more friction has to come from somewhere.
So, if you've got an '86 with a clutch driving you crazy this might be a fun project to undertake. If you had the shim fabricated before hand it would be a pretty quick job, wouldn't even require removing the side of the case, just the clutch cover. Happy Riding!
