Gearing up for a sidevalve


So Arthur Pentney (OBM Letters July) likes his Norton sidevalve solos but not his BSA M20 which was “somewhat heavy and ponderous and lacking cornering ability” – could this be because he was talking of a rigid model with girder forks?

Not so the postwar 600cc M21! My plunger one with teles and the wonderful eight-inch front brake is a terrific steed for getting around town.

I’ve had it for many years and did tens of thousands of miles on it, combo and solo, with a 16-tooth sidecar sprocket – at a max speed of about 45mph!

Article continues below...
Advert

Enjoy more Old Bike Mart reading in the monthly newspaper.
Click here to subscribe & save.

I always knew it could pull a much higher gear so eventually l put a 19-tooth engine sprocket on.

Read more of this Letter and other Letters, Opinion, News and Features in the September 2019 issue of OBM – on sale now!


Advert
Subscribe to Old Bike Mart Enjoy more Old Bike Mart reading in the monthly paper. Click here to subscribe.