> Born to be WillD Wrote:
> OK, the wallowed out clutch spline is a thing that happens and almost
> certainly your probelm. it happens if the shimming is wrong or the
> spring washers not tight the clutch pieces seem to be able to tilt a
> little rather than slide in and out smoothly and they wallow out a
> groove, but once it starts getting bad they will get stuck in the groove
> and that prevents them from being adequately compressed together and
> engaging, and so it slips. Usually you notice this either being super
> hard to get it to engage with the starter clutch, or conversely from a
> stop the engine will rev high and then clunk into engagement as it
> overcomes the groove, sounds like yours is never getting past that
> groove and looking at it, it's easy to see why. that thing is thrashed.
> It's fairly common, but never that bad. usually you can file them with
> small file and get it to slide smoothly. Also check that nothing is
> crooked or warped the plates, and that the clutch donut doesnt have any
> stuck together segments or twisted sections or anything. replace with
> the good spline piece, and you should be OK at least for a while.
> Regarding the flywheel keyway, unfortunately that's also common, but
> it's not directly related. I think that winds up happening because
> people love to skid stop the coaster brakes, which immediately locks up
> the rear while the engine is still engaged and trying to spin and it
> clunks the flywheel like an impact. it's alotta imact, and maybe that
> also contributed to your clutch problem but i dont think they're causing
> one another, just maybe symptoms of the same abuse.
> Anyway, you don't need that key. You can absolutely get away with
> grinding down any raised sections, removing the wrecked key entirely,
> and using the valve lapping method to clean up the taper. as you do it,
> check to make sure it's all getting shined equally - no high spots. once
> it looks even, set the timing where the key would have been, and tighten
> it on. the press fit onto the taper will hold it exactly where you put
> it. Lapping may require you taking the crank out tho, and at that point
> might as well replace the whole crank, you can probably find a good one
> on here or get a fancy one somewhere. Dos cycles has some A cranks, if
> not on their site just email them.
> I've run several sachs and other peds with a lapped crank and just press
> fit onto the taper at the right timing. it's totally fine, all the
> woodruf key is really for is lining up the timing.
> Anyway that should get you where you need to be. good luck
The reluctant Sachs Guru speaks, and it is so.