cruising speed on model20

54ajay · Post by **54ajay** » Thu Mar 18, 2010 7:22 pm

i have been riding a 1954 model 20 regularly for around 3 years now and was wondering what a normal comfortable cruising speed would be for this model. The bike goes up to 45mph easily after this she seems to be revving highly and i dont want to put the engine under any undue strain i never take a pillion and there are no signs a sidecar has ever been fitted

Groily · Post by **Groily** » Thu Mar 18, 2010 9:45 pm

Ah! The comfortable cruise . . .
It should go a bit beyond 45 comfortably on standard gearing, but they are a bit buzzy. Not many bikes of the era were capable of the revs we can do - but revs on their own never killed anything.
I and one or two others I know are happy to cruise at 55mph/90kph on early models. But not much more. By cruise, I mean 'run for miles', not just to the end of the straight bit in front of you.
If you were to stuff a 17 toother on the gearbox instead of the standard 16, you'd be OK up to 60-ish although head winds and hills can be a pain. I am told by folk who have speedos that work better than mine that my sweet cruising speed is 58mph with the extra tooth, or about 53mph with the standard one. I have the personal profile of a lead brick.
2-up is emergency only with the darn silly short seats we're supplied with and my big bum.
If pressed, however, the thing will run at 65 or more and won't blow up unless it's unwell, although it might do something for the oil consumption. As mine has over a quarter of a million miles on it, I tend not to push it too hard, and stick in the 50s. I'm not usually in a hurry, or I'd have taken something else out.
So I'd say 50-55 should be OK assuming you have the standard crank sprocket with however many teeth that is.

wilko · Post by **wilko** » Fri Mar 19, 2010 12:00 am

My mate is always in front of us sitting on 65 (true) so i think you're being a little nervous. Remember they're good for 90 mph. Here in Oz with our wide open spaces it's always a good idea to up the g/box sprocket to 17 tooth. You can cruise on 50mph on an old BSA M20!!

bell · Post by **bell** » Fri Mar 19, 2010 5:15 am

Speak to Brian Lingard in the Poachers Section , he has riden one for over twenty years & he shows it no mercy . Regards Richard .

paul knapp · Post by **paul knapp** » Fri Mar 19, 2010 12:20 pm

You can cruise on 50mph on an old BSA M20!!

................LOL !

1608 · Post by **1608** » Fri Mar 19, 2010 3:06 pm

My old M21 outfit, cast iron head, used to cruise all day at 50 mph,bomb proof engine.

54ajay · Post by **54ajay** » Fri Mar 19, 2010 3:15 pm

thanks for that fellas think i might have been worrying too much didnt want to start taking liberties and abusing the old girl

wilko · Post by **wilko** » Fri Mar 19, 2010 10:47 pm

Paul you ol' skeptic! Come up to Nagambie one day and we'll give you a ride on one of my mates old hacks, it's quite surprising! (M20)

moley · Post by **moley** » Sat Mar 20, 2010 7:26 am

i have rode both early and lat 500 twins and find the early 50's one to be gutless nut the later 50's one to be suprisingly sprightly..regards

Groily · Post by **Groily** » Sat Mar 20, 2010 6:14 pm

I'd agree with that Moley.
A mate with a late one is happy at 65+; with a '54 model I'm not, although it'll do it. A good improvement on mine was the recent fitting of a later inlet camshaft, which has certainly improved things, but when all's said and done, 60-ish cruising with a 17 tooth is about what it's good for in my case. Maybe I'm too soft on it . . . it was maybe better way back when when it had original wire-wound pistons - smoother, quicker, nicer to ride - and separate exhausts rather than siamesed. But I was younger and madder then too.