BSA 1939-1955 C10 Three Speed Gearbox Strip and Rebuild

It is hoped that this video may be helpful to anyone about to embark on a strip-down of this type of gearbox by sharing the experiences of the author.
The video shows the strip and rebuild of the BSA three speed gearbox as fitted to 250cc BSA bikes from about 1939 to 1955, the number on the casing is 29-3255.
It is simply a basic strip and rebuild, it does not go into detailed examination of individual gears or components.

[@vivbaker5139]

At last I will be able to replace my kick start spring. Many thanks for taking the time to make this video.

[@saxophrage]

Glad that this video was helpful. I enjoyed making it and it's good to know that it has been of some use in the preservation of these fascinating old motorbikes. Thank you for your comment.

[@olliehurst8674]

Great video for people doing restorations/rebuilds. Good work!

[@roydevries6537]

Many thanks. Most informative. Cheers

[@charuduttshirpurkar9791]

Excellent video .I am having same three gear boxes.

[@mvwdederde3393]

Great! Just what I needed!!

[@thelaird9195]

Great help with my C11 restoration. Any chance of an engine rebuild video.

[@47dirtyden]

mmm brings back memories of C11 g/box o/haul I did waaaaay back in 1965 when I was18 & hadn't a clue what I was doing, the layshaft gear had lost teeth which I had to replace, this was due to oil loss as the box leaked badly

[@saxophrage]

Thank you for your good comments. From what I can gather this gearbox was famed for its oil loss. Mostly folk would use grease or a mixture of grease and oil in the hope that being thicker it would take longer to leak out. It was also good to retain a stoic attitude that the leaking oil would keep the rust at bay:)

[@anzacforever832]

Is there no gasket between the 3 cases

[@markmarriott4720]

Thanks for this. Really helped me out with mine. Do you want to do the c10/11 engine now?

[@rez1378]

Hi sir, can you help me, i have some problem with 1 & 3 gear, that gear not long to stay at they position and then jump to neutral, what should I do to fix that.. thnks before.. (sorry for my bad english word)

[@wealthyglistensiahaan6830]

Hi Sir. I have same type of gearbox but its pawl carrier plate was not inside. Does any one knows where to get that ? or have drawing to follow to re-create a new one ?..Thanks a lot

[@saxophrage]

Thank you for your comments. Finding parts for this ancient gearbox is becoming increasingly difficult, although they do come up from time to time on the usual online auction sites. Failing that there are a couple of websites that specialise in parts for vintage British bikes. I seem to remember having some success with one located in the UK having a name something like DragonFly.
Good luck finding your pawl carrier plate, and with your restoration !

[@rusiruliyanage1971]

Great video