Hi, I have a B22 1937, which I believe has a few non-standard mods. However, I have not found a detailed authoritative document or pictures which prove or disprove my assumptions. I would therefore be very keen to contact other B22 owners with a view to sharing details and the odd photo for clarification. I would love to hear from any fellow owners of these lovely machines. Cheers
The parts book is the first place to start.
A few changes were introduced during the 1937 season though, notably the pushrod tunnel top end and rockerbox, and the frame lugs and rubbers for mounting the oil tank.
Thanks Rupert. I have one on the way. The main mods I think my bike has are an additional screw to the left of the Pressure Valve Screw, plus my gearbox is non-standard but I can't tell from which bike! I have written to Sammy Miller for advice so hoping to hear back next week. Cheers
If you post a pic of your non-standard gearbox we can all have a go at identifying it! What larks Mr Pip!
Most likely are earlier 30's or early post war (46-48 B series) gearboxes as they have the same "bottom slide" method of fitting. Any gearbox from a different make would need major surgery to fit. BSA C range is also a possible.
Thanks Rupert. This shows the gearbox and the additional screw, immediately left of the pressure valve screw.
I think the gearbox may be from a B31 or similar!?
Yep, postwar B series box B31 and B33 1946-48, XB and YB models. Its a straight swap for your original box, no modifications needed.
Quite a lot of the internals are interchangeable with the pre war box.
The extra screw under the timing cover, would be worth investigating to see what it does and why it was fitted by someone...
Thanks again. Yes I'm tempted to remove the screw but my instinct is leave well alone until I learn more about why it might be there. I have emailed Sammy Miller for some advice. Hopefully he'll respond soon. A google search suggested it might have been done to assist in removing an old main bearing but I don't know how valid that suggestion might be!? Cheers
The main timing side bush is a long way inboard from there and in a higher position.
From the pic it looks to be in line with the oil pump driving spindle. If it is in line with the oil pipe stubs drilling there would hit the oilway from that first before the spindle. Either way, no good reason for it to be there, the things people do...
Hi again Rupert. You clearly have a lot of knowledge of these bikes. Where might I find an exploded diagram of my bike's components. I have the Parts List but that doesn't really help with how it all goes together. Plus, I didn't understand the reference to the different B31 models in your previous answer. Is there any information on both types you could email me a link to? Very grateful for any help. Cheers Martin
I only know what I know from building a couple of the 37-39 B series bikes and collecting bits for a couple more. I'm still learning... but they are fascinating things and are often overlooked.
Exploded drawing?? Havnt seen one yet. Julian Snook may be worth asking for anything related he has.
X was the dating letter for all models (eg B31) made 1945-47.
Y was for 1948.
Similar to H for 1937 as on your bike.
Happy to provide you with pics of engine internals if you provide your email address, if that would help.
Thanks Rupert. I've sent you a PM with my email address. Cheers M