I have owned a 1946 B31 for for around 12 years and I cannot figure out how to avoid the centre stand hitting the exhaust pipe when pushing the bike off the stand. This is despite the bike being fitted with an apparently plunger silencer with an indent underneath to avoid such a problem. I would be grateful for any help on this problem. Keith
my M21 does exactly the same as well as bashing up and down from tarmac to exhaust when going over potholes. I have temprarily put a spring on it which i slip on and off after starting the engine. This is not a very good solution. Toying with the idea of getting/making one of those older stands which bolt onto the frame near the rear wheel axle. I would also be grateful if someone in the know would solve our mutual difficulties!
Hi,
I would say that the springs are either a bit tired or not strong enough. This bashing up and down can happen on any bike but hitting the tarmac more likely on the lower slung ones. It could also be that the 'stop' part of the stand and frame is worn allowing the stand to come up a bit too far and hit the silencer. Have a look at the contact points between stand and frame. They can be welded up and filed/ground back to correct shape.
Dave.
Hi Keith
I assume from the date that your bike is similar to my B33, rigid and with the 1946-48 gearbox.
The stand I have has a bump, as in the picture, which limits how far it folds up. If yours is the same you could try just cable-tying a piece of hard rubber to the frame tube where this usually contacts ( I do this with brake levers/ footrests) or build up the "bump" with weld.
er...the picture is bigger than intended but..................
(https://i.ibb.co/cX3QZ4g/main-stand.jpg) (https://ibb.co/prwdMY0)
Hi Pete. Thanks for your reply. Yes, my stand is the same as yours but there is no obvious location for the stop part to hit the frame. It's near to a position where two tubes join at right angles.
Does your silencer have a scalloped section on the underside to allow for the stand to sit higher when folded up. Mine does but according to Armours this was first fitted to the plunger models. Without this indentation in the silencer, the stand would hang pretty low when riding.
I have two of these bikes, one of which I am restoring. I am well on the way and now only need the exhaust, the chains, a battery, wheel builds and the rear brake tie bar which is proving to be difficult to find but at least I have a pattern on the other bike.
Keith
I can't remember seeeing a scalloped section, I'll have to have a look next time I'm in the garage. I do remember seeing one silencer with a few dents on the underside but there are 2 B31s, an M20 and M21 lying around the place so could be on any of them, or in the spares/scrap section.. ;D
Thanks Pete. Could you also look to see if you have a spare rear brake anchor bar please. Thanks -Keith
I couldn't find any indentations in the silencers fitted to any of the plunger or rigid bikes. On the rigid B33 the "stop bump" on the stand contacts the frame cross member behind the gearbox and stops the stand hitting the silencer by a few millimeters only.
Sorry, no spare brake anchor bars lying around, in fact I couldn't find the one that should belong to an M20 project so I will probably have to knock one up one day..
Pete