Building a BSA B31/B32/B33/B34 from parts. Episode 8 of many - gearbox reassembly is easy, right? 

I did enjoy the time lapse sections !

One of my first big spannering jobs was putting a new cluster in my KH250, cos it kept jumping out of second. Went up to London, got a cluster from a breakers in Leytonstone, took it back home, fitted it tothe motor on the kitchen table, and it did just the same on the test ride. Apparently, they all did, after a while.

Well done , think would have ended. Up using my 2lb hitting stick . Looking forward to part of the gearbox instalment .

Quite interesting as I am rebuilding my A10 Gearbox. Just waiting to get the re ground layshaft back! Many thanks for the video!👍

Just put my B31 gearbox back together (video out soon)... yes fiddly to reassemble... BSA service sheet in brief: fit camplate and plunger, set to neutral, place layshaft, fit first pair of gears together with selector fork, fit mainshaft first pair of gears and their selector fork, make sure fork pins are in camplate groove, slide in fork selector rod and fit grubscrew, fit washer and final large gear to layshaft, fit mainshaft into inner cover with kickstart ratchet mechanism, gear selector rocking lever and push into gearbox making sure the dots on the rocking lever are aligned (neutral position). Haynes manual has a different method! I followed the service sheet except I fitted the mainshaft then the inner cover (easier). Fat fingers a hinderance! I think BSA must have employed ladies to do the gearbox assembly.

Obviously not a "how to video" but a "how not to" video!!. Nice to see that it eventually went together though.

I thought the gasket gloop was Red Hermetite, but that looked like some modern equivalent, Red Hylomar perhaps? Very impressed by your patience, there would have been copious effing and blinding if I was doing that job.

Regarding the clutch arm in the outer cover, the wear is usually worst in the direction that the arm moves…which must reduce the lift at the clutch pressure plate by that amount…not a good thing, especially if you have a 6 spring clutch. If you fit a bush it needs minimum interference or it will bow the outer cover. The temptation is to then flatten the outer cover on the gasket side by grinding, etc. This then screws up the gear change quadrant engagement…

Bit late to this party…but for future reference, give yourself a fighting chance! Put the gear change detent plunger in and select neutral…then start filling the box with gears…

Hi you can put the shafts in both together with forks then fit fork pivot shaft after, it would help if you had case other way up in vice to , cheers Bill

When you find washers missing and wrong screws/bolts it’s a worry about what you can’t see

Hope you don’t miss out the rest of the g/box , I’m about to take mine apart & will need to know how to put the kick start back together .