AJS & Matchless Owners Club

Hello

I am in need of a bit more help please

My 1956 G50S has been a pig to start recently with it spitting back and the kick start trying to take my ankle off so i thought i would start with the timing and look at the auto advance unit
Upon inspection it appeared to be locked solid so i tried to loosen it off with it on the bike with not much success although it did ease off a bit , so i have taken it off and i now realise that i do not understand how it is supposed to work. The unit is free on the bench but when back on the engine and the chain is added and the unit is nipped up on the taper with the central bolt it goes very tight again - is this supposed to happen or is something missing ? Should i be able to open up the weights as i presume this is just rotating the magneto ?

Also on the same area, what to you lubricate the chain with ?

Thanks in advance
Trevor

On the bench the unit should open and flip back quite easily. They do wear on the pins retaining the weights. However if the chain is too tight the system will fail to work. Sounds as though this is your problem. There needs to be a fair bit of slack in the chain, but not enough to let it hit the case. You will need to recheck your timing after slackening the chain. Also remember to jam the unit open when setting the timing so you have it on full advance. (tighten the unit to the magneto and set the timing with the cam sprocket loose or its a pig to get right). The only lubrication I use on the chain is a good dollop of grease spread around it.

Clive

You are a genious sir

Two hours of fiddling about this afternoon and upon your comments its sorted in ten minutes
As you said the chain was too tight !

Many Thanks for your help
Thanks
Trevor