The gearbox and gearchange on my '73 Triumph Tiger 750.
The change has been terrible since I got it as a non-runner import from Toronto. Got it running, legal and on the road, and the go and stop is fine. But the gearbox has been horrible - missing gears, false neutrals etc - but no mechanical nasty noises.
Had 3 goes at sorting the change, eventually replacing all the pingfuckits that make up the positive stop change mechanism - and that made it worse! So, today, after a lot of research, I decided to open up the gearbox itself. Had some difficulty in getting the pinions off the 2 shafts, because they are held in by 3 selector forks which in turn fit into a camplate that must have been designed by Stan himself, in the days before CAD. Clever boys those men from Meriden, RIP etc.
Was somewhat heartened by the general good condition of the internals, so there was no mechanical calamity causing the problem, but did find a thrust washer that looked as though it had fallen off its locating peg when the PO assembled the 'box last and could have caused lateral positioning errors of the gears along the layshaft.
Anyway, after a good sniff around, and with the workshop manual to hand, I took my time re-assembling the work of Stan, according to the manual. After a few "ah, that's how it goes" moments, got it all back together, and now it feels like I think it should, or rather as how I remember Triumph gearboxes from 35 years ago.
It all seems to work, but I'll give the gasket goo overnight to go off before I refill the oil and, if it's stopped pissing down, try a road test. Can't be any worse......
EDIT: Sorted. All gears now available on demand, and predictably. 2nd to 3rd sometimes iffy, but I know why and a bit of use should sort that. Phew. This has been a 'journey'. At leasI now know intimately the workings of the Triumph gear change and gearbox mechanisms. All knowledge transferrable to my '72 Daytona 500, now in build.