Hi, sorry to make my first post a plead for help, but i have reached the end of my ability with this problem. I have this 1948 BSA B32 which I bought a few weeks ago. It has the original gearbox, which I believe was only used by BSA for a few years.
I removed the inner gearbox cover and failed to note the position of the selector quadrant. I also do not know what gear the bike is in.
I have been trying by trail and error for around 8 hours to reassemble it correctly, but I can never get access to all the gears. My method of testing has been to replace the inner cover and turn the quadrant using a spanner, so sans gear change mechanism. Is this an ok way to test the gear selection? My main problem is that i do not know which gear corresponds to which segment of the selector quadrant; also i need help in getting the gearbox into a known gear.
Thanks for replying. i have a book with all the service sheets in, they have not been helpful thus far. I suppose i can assume that the position shown in the fig b.14 is either 1st or 4th? Part of the trouble is i have no clue what gear the bike is in, the gearbox is still in the frame, which obviously makes things harder, but i am reluctant to remove it as it do not have the necessary tools to remove the clutch
Hello Jacob, AFAIK the position shown refers to 4th gear position. There should also be a centre pop mark which will correspond to a line or centre pop? on the selector shaft actuation gear (there was on my 1952 M33 gearbox). If you refer to Service Sheet 608 this may help you better. HTH
In 4th the sleeve gear is locked to the main shaft by the furthest away selector fork pushing the mainshaft sliding gear into the sleeve gear, you want the gearbox to be in this position and then follow fig B-14 for the selector quadrant.
It appears I have been a fool and have made a stupid error.
I have previously had the inspection cover off, but I have been doing all this work with it on.(As the box is in the frame, I wanted to prevent debris from falling in.) So I decided to remove the cover and had another attempt at refitting the selector mechanism. This time everything worked; i could access all gears. I think i must have had the cover on upside down. I just tried refitting it, and it seems as though it will foul one of the selector forks if it is mounted wrong.