Cams and ignition timing

Information relating to the Matchless G85 500cc Heavyweight, AJS 7R, Matchless G45 and Matchless G50
bjorn
Member
Posts: 69
Joined: Mon Jan 01, 1990 12:00 am
Location: NORWAY

Re: Cams and ignition timing

Post by bjorn »

On exhaust pipe sizes:

The '55CS has a 1.5" pipe. The '56CS has a 1.75" pipe that fits between the B52 Box and the footpeg. The footpeg is scalloped at the top to give clearance.

Bjørn
Braaap
Posts: 75
Joined: Mon Jul 09, 2018 10:24 pm
Location: New Zealand

Re: Cams and ignition timing

Post by Braaap »

The only advice i can offer re finding correct jetting, is; always jet downwards.
Fit a huge jet... and the bike should blubber on full throttle. Then jet down until it is happy.
If u start your experiment with a lean main jet u may wreck your engine before you discover the correct setting.

Slightly different issue for my G3L last time out... she was cutting out when ridden at a steady half throttle. Eg. On the needle. Investigation revealed the needle clip had let go and the needle was rattling loose, and pretty much blocking the fuel off.
Motor was running very lean, getting hot and grabbing the exhaust valve stem.
Ran ok at full throttle tho. Not sure how 😅
Locked