Reassembling a '78 R80 5-speed tranny, won't shift right...
Posted: Wed Mar 09, 2016 6:11 pm
I'm reassembling a '78 R80 5-speed after a failed-bearing problem, but when I install the shifting mechanism, it won't shift through the whole pattern, hanging up after clicking from 1st through neutral and (sometimes) into 2nd (sometimes stopping before the spring-loaded roller cam drops completely into the round groove for 2nd), sometimes locking up there completely (no movement up OR down).
Any thoughts, or information you could point me to?
Secondarily - maybe a problem, maybe not - the top (largest) gear on the one shaft has about 1/4" of up-and-down play in it that keeps the other shaft gears from hand rotating when gravity lets the large gear drop down to its resting height when the trans is on the workbench. Raising it up by hand that 1/4" allows both shafts to rotate.
Any idea what's up with that? Maybe the gear "dropping down" won't happen when the trans is horizontal in the bike, but the idea of it sliding over that little bit and locking the gears up at speed bothers me quite a bit.
I DID NOT disassemble the gear shafts when I replaced the bearing, so everything should be as it came out, and I'm mystified as to why there should be that play in the large gear - as if there should be some spacer to hold it in its correct position.
Any thoughts or help would be MUCH appreciated!
Any thoughts, or information you could point me to?
Secondarily - maybe a problem, maybe not - the top (largest) gear on the one shaft has about 1/4" of up-and-down play in it that keeps the other shaft gears from hand rotating when gravity lets the large gear drop down to its resting height when the trans is on the workbench. Raising it up by hand that 1/4" allows both shafts to rotate.
Any idea what's up with that? Maybe the gear "dropping down" won't happen when the trans is horizontal in the bike, but the idea of it sliding over that little bit and locking the gears up at speed bothers me quite a bit.
I DID NOT disassemble the gear shafts when I replaced the bearing, so everything should be as it came out, and I'm mystified as to why there should be that play in the large gear - as if there should be some spacer to hold it in its correct position.
Any thoughts or help would be MUCH appreciated!