rear brake drum circlip

Information relating to the Matchless G12 or AJS Model 31 650cc twin
Locked
John Carney
Member
Posts: 30
Joined: Tue Dec 29, 2020 10:13 pm
Location: JERSEY

rear brake drum circlip

Post by John Carney »

Hi,

I've had an issue ( see earlier post ) with the speedo gearbox jamming.

On further inspection with the wheel off I've noticed the rear brake drum circlip is not home properly and try as I might I can't get it to re seat. There is a small amount of play on the washer behind it but not enough to push it home.

I don't want to open a can of worms but wondered if anyone has encountered this or has any thoughts how I can resolve it.

thanks, John
You do not have the required permissions to view the files attached to this post.
John Carney
Member
Posts: 30
Joined: Tue Dec 29, 2020 10:13 pm
Location: JERSEY

Re: rear brake drum circlip

Post by John Carney »

I thought if I can get the rear brake drum off to have a look on the bench I might be able to see why the circlip doesn't have the groove visible to push it home. I suspect it may just be overpacked with grease, or the brake drum bearing may need to be pushed in further ??
I removed the chain, and nut holding the brake cover plate and drum onto the frame and its all loose but the rear brake drum won't come away ? I would take this into somebody who knows, but the currrent waiting list here is 1 to 3 months so I'm hoping to resolve myself if its possible. There doesn't seem to be anything that covers this in the instruction book.
User avatar
Duncan
Member
Posts: 2118
Joined: Thu Jul 10, 2003 1:00 am
Location: HAMPSHIRE UK

Re: rear brake drum circlip

Post by Duncan »

The dummy spindle has a cutaway in it for the swinging arm, pull it to the rear of the bike to remove it and the sprocket, you will need to ensure that the brake torque are is clear of its register and the through bolt and spacer through the chain guard removed. The dummy spindle can then be removed from the bearing and the dust shield removed from the back of the bearing, you should then be able to see if the bearing is fully home.
John Carney
Member
Posts: 30
Joined: Tue Dec 29, 2020 10:13 pm
Location: JERSEY

Re: rear brake drum circlip

Post by John Carney »

Hi Duncan, that explains things, :D got it off and apart now. I should have done this a while back to check the brake pads anyway but have been putting it off as I couldn't see how it was done. The bearing needs to be moved slightly so I'll take it in to a garage to get it moved with a bearing puller. thanks for your help :)
mdt-son
Member
Posts: 373
Joined: Wed Feb 01, 2012 1:22 pm
Location: Vestland NORWAY

Re: rear brake drum circlip

Post by mdt-son »

Not sure how you intend to use a puller on ball bearing 021598 as the outer race is buried in the QD brake drum. There is no restraint for a puller. Gentle pressure on the inner bearing cup is the way to go (heating with MAP gas may ease the tight fit somewhat). If you want to replace the bearing due to age, it can be knocked out from the drum side by applying pressure on the outer bearing cup. Use of heat is not prescribed in the workshop manual but may be beneficial. A deformed circlip should be replaced.

- Knut
Locked