Questions? Looking for parts? Parts for sale? or just for a chat,

The WD Motorcycle forum

WD Motorcycle forum
Start a New Topic 
Author
Comment
BSA WM20 rim sizes

What size rims were fitted? I’ve heard early models had WM3 and later WM2 or was it what was available at the time? Also what is the largest tyre that will fit on a WM2 rim? 3.25? Thanks in advance!

email (option): fordmadowners@yahoo.com.au

Re: BSA WM20 rim sizes

I think all BSA M20s are WM3, but Norton 16Hs are WM2, they all use the same 3-25 19 tyre.

Rob

email (option): robmiller11@yahoo.co.uk

Re: BSA WM20 rim sizes

The REME M20 standards book shows WM3 rims front and rear...I fit a 350 tyre front and rear...It's possible to get larger tyres onto that rim size but frankly, with a 400 fitted on the front the bike handles like a barge and that size can't be fitted onto the rear unless deflated first and with perfect wheel alignment, as there are clearance issues...
So, for practical road use the 350 would be the best choice IMO and visually fills the front mudguard a bit better.....I use my bike for limited off road use occasionally and really a 325 would be a better choice for that, particularly in soft conditions like sand or mud...I manage with the 350 though...Ian

email (option): ian@wright52.plus.com

Re: BSA WM20 rim sizes

Thanks for the reply’s there is a wealth of information here.
So is it the general consensus that all WM20’s were fitted with WM3 rims? Or some WM2? Or was WM2 for civilian models only? Regards.

email (option): fordmadowners@yahoo.com.au

Re: BSA WM20 rim sizes

Ian Wright
The REME M20 standards book shows WM3 rims front and rear...I fit a 350 tyre front and rear...It's possible to get larger tyres onto that rim size but frankly, with a 400 fitted on the front the bike handles like a barge and that size can't be fitted onto the rear unless deflated first and with perfect wheel alignment, as there are clearance issues...
So, for practical road use the 350 would be the best choice IMO and visually fills the front mudguard a bit better.....I use my bike for limited off road use occasionally and really a 325 would be a better choice for that, particularly in soft conditions like sand or mud...I manage with the 350 though...Ian
Hi Ian

I plan to use my late 1944 WM20 on the road would the Mitas H-02 3.50 X 19 be ok? On the website it specifies for the M21 and the 3.25 X 19 H-01 for the M20, how close is the clearance for the 3.5?

Re: BSA WM20 rim sizes

Tod I have the Mitas H-02 350x19 on several of my bikes and done 1000's of miles on them over many years. They are not a large 350 tyre compared to some others and will fit easily on an M20. There is no physical difference between an M20 and M21 anyway. Ron

email (option): ronpier@talk21.com

Re: BSA WM20 rim sizes

['So is it the general consensus that all WM20’s were fitted with WM3 rims?...]...That's right...Ian

email (option): ian@wright52.plus.com

Re: BSA WM20 rim sizes

You lot are spoiled for choice
when available I fit a 325 front and a 350/400 rear
I never understand metric tyres but I think a 90/90 fits but the 90/100 & 100/100 does not
And yes WM3 front & back

Nieuwe pagina 1