BSA Owners' Club Forum

The BSA Workshop => Singles => Topic started by: blackdog on 24 July, 2017, 20:59:24

Title: M21 wheels
Post by: blackdog on 24 July, 2017, 20:59:24
Hi, can any one help with the configuraton of the wheels on a 1961 M21. The rear wheel is 'quick release' and is currently slightly off center. The hub will not push fully onto the driving flange as the bearing sleeve will not let it. The hub only sits into the driving flange by about 3/8" which does not seem right. If it pushed on further it would probably be ok.

The front wheel (7" hub") again seems to sit too far over to the o/s. The diagram I have of the set up shows a spindle sleeve going through the bearings however my spindle fits the bearings perfectly and there is no sleeve. I put a distance piece between the bearings and all seemed well until I put the wheel into the frame. The diagram also shows a nut fastening the brake cover plate on but as I have no spindle sleeve I cannot do this. If I push the brake plate up to the stantion sleeve and locate the plate stud into it to stop it spinning there is around a 1" gap on the spindle to the n/s and the wheel is off center.  If any one has any photographs of their wheel set up or can advise how the configuration should be I would be grateful.

Hope the above makes sense  :o

Title: Re: M21 wheels
Post by: JulianS on 25 July, 2017, 20:07:22
I thought the post 1956 M21 was fitted with the 8 inch single sided front brake which is a different setup to the 7 inch one.

I wonder if you have a mix of parts in your front hub?

Can you post photos they are worth so much more than words in these situations.
Title: Re: M21 wheels
Post by: JulianS on 26 July, 2017, 10:27:34
The other possibility with 7 inch front brake is that it is the similar type used on some unit singles. If the whole wheel is from a unit single then, as the offset is different  due to different fork centre measurements, the rim will be off centre for your bike.

Photo is from C15 parts book and shows the setup used on some competition models, similar used on some B44 and C25. No nut to hold brake plate and spindle which runs in near side bearing with no sleeve.
Title: Re: M21 wheels
Post by: blackdog on 26 July, 2017, 14:59:07
Hi Julian It is the same as the diagram you have posted so that would explain why the front wheel is off center. I will take a picture of the rear and post it. Thanks for your help.
Title: V twin 1930 BSA kickstart quadrant
Post by: Julian lee on 26 July, 2017, 16:57:57
Hi can anyone please help me I need a kickstart quadrant for a 1930 BSA 3 speed gearbox on a y13 v twin please ring Julian on 07706912974