Re: Drat! Crack in Gearbox Between Main and Lay on Drive Si
Alrighty something I'm most expert opinionated on, broken drive train components. AMC shell is as much or if not a bit more properly designed for indefinite service as the dumb atom splitting axle. Applying hobot logic and findings to what I now call the AMC cleavage. To part as much as join. I'm in Swoohes camp on this, its just a matter of time. I have a long list, 3 pages of vendors I collected world wide d/t crank BF and AMC shell repair or replacement. There are literally piles of cracked and worn bores AMC shells in vendor shops all over the world. Call a few biggies if ya doubt me - again.
Even intact what structural support can such a thin section provide? Do ya really think that thin bridge is whats keeping the bulk of the surround metal from going separate ways. I don't think so. Welding is for the birds here, unless can build up more support bulk, not, and well known to weaken-soften Al - witness the head welding reports. I'd go with JBW if it cracked to leak and warm cases and use magnets to draw it in deep to set up, a few days.
The real issue is the bores tight round enough to restrain races from spinning and line boring accurate enough if wallowed out from prior spinning, but what to fill in with that don't weaken and distort, comoz says JBW here too.
My destructive investigations for my expert opinion is the fracture damage is not do too skipping rear tire down shifts or clutch drop wheelie red line launches but doing this with too worn and loose bushes so clutch basket can be seen to wobble plus just one good over tight primary chain event. I find that w/o the sure even supporting bush fit the shaft shift off center more to bow so the shaft ends lever and wobble the bearings apart. Snap.
I've done all of the above and took teeth off cogs and bent shafts and augered out the bores but so far no cracked cleavage. So If'n me I'd just renew everything but the cleavage and do it again at first hints of basket wobble.
I had a Qualife repaired by Ken Canaga that had almost torn its lower mounted bolt boss off one end and cracked the other, its bores are visibly scored by races spinning but by golly its same size cleavage is intact. I got so pissed at my first shell with loose bores the bearings fell out cold I bashed the main shaft one right out the back side full circle but dang web is still intact. Go figure - they weren't made to last anyway, just a stop gap for the Rotary wonder.
Oh yeah results of world wide pestering reveals Atlas shell half the cost and twice as easy to fit w/o the stupid thick washer spacer extra hassle mass.
