konrad

I am so grateful for the help I received with my gearbox I want to give something back to this forum. I'm a retired electrical engineer and a hobbyist machinist. I have done a fair amount of work reverse-engineering the TR280i's electrical system. Cheers. I have replaced the .PDF file with an entire website: https://www.ossa-efi.com/home It corrects some errors and omissions as well as providing greatly increased technical content.

Peter, that was hugely helpful! Thanks a million! I never would have "guessed" that solution. Here's a pic for the next poor ******* who has to tackle this problem. The grey screwdrivers eventually worked. The red and green were too small. It helps to have the gearbox held rigidly (I lightly clamped it in a vise) when first moving the circlip. I had to progressively move the circlip along the shaft as more and more wiggle room became available. Eventually, everything just fell apart. I tried the pallet knife shown between the circlip and the adjacent gear, but it was not helpful. I removed the circlip completely as I did not want it stretched while I wait for bearings to arrive.

I now see 3 circlip locations, but none look like they would allow any gears to then be removed. Much more information here: https://www.ossa-efi.com/home/engine/gearbox

This is great information, papapitufo! Thank you! I have a question and an observation. How do you remove the secondary shaft (where the drive sprocket attaches) to get to the point shown in the first photo? I see two inaccessible snap rings, and that's all. I believe there is an error in the second bearing part number. MT280232043 appears to be a Torrington bearing for the “clutch pump piston” (OSSA equivalent 173002RA). I think we actually want to also replace two MT280432039 (30x33x10) bearings while everything is apart. These are the bearings on which the clutch basket turns.