AJS & Matchless Owners Club

Is there a recommended torque for the four sleeve nuts on the long through bolts?
Steve

Please see attached.
http://archives.jampot.dk/technical/Ser ... 61_no6.pdf
Looks like 40 foot pounds.

Yep 40 lbs it is if you're brave enough! I chicken out at around 35-37 and also use a head gasket rather than lapping the joint as I only run on the road and can't be bothered continually lapping in the head joint. Gets rid of the persistent weeps.

I do the same as Rob.

Colin

40 ftlbs in accordance with literature was what I did previously. Going the last bit from 35 to 40 always felt like it was a bit too much. On assembling my latest engine I asked Danish G80CS specialist Carsten Kuhl what he uses: 4kgm (or about 40 Nm) was the answer, any more than this doesn't help!
He knows what he's doing, so I took the advice and torqued down to 30ftlbs. Felt more correct than the 40ftlbs I was used to. No head leaks! I don't use a gasket and very rarely (almost never) need to lap head and cylinder together.

Regards
Bjørn

I decided on 30 lb ft too, in the end. With a copper gasket too. Firing it up tomorrow for the first time in months since a big end repair. Wish me luck!

How is the riding weather in Norway? It must be getting towards the end of the season for you I imagine.

Best wishes
Steve

30 lb ft turns out to be fine, no compression leakage.

The later models seem to be 42ft/lbs and in my ingnorance used to use 50-55 thinking this to be better, but no all that happens is the barrel expasion is too much and the sleeve nuts neck or even snap. So use the factory figure and you must check after 100 miles or so after a new rebuild because they will be need torquing up again , otherwise it will leak.

A repost of my comment from last year.
"40 ftlbs in accordance with literature was what I did previously. Going the last bit from 35 to 40 always felt like it was a bit too much. On assembling my latest engine I asked Danish G80CS specialist Carsten Kuhl what he uses: 4kgm (or about 40 Nm) was the answer, any more than this doesn't help!
He knows what he's doing, so I took the advice and torqued down to 30ftlbs. Felt more correct than the 40ftlbs I was used to. No head leaks! I don't use a gasket and very rarely (almost never) need to lap head and cylinder together."

I do have some very slight oil weep from the cylinder to head joint. This however, is always from the push-rod tunnels seeping past the thin rubber o-rings. These, as supplied from the club are not really up to the job. Viton o-rings can better cope with the high temperatures.

Tightening above 40ftlbs is asking for trouble. As John points out, the sleeve nuts can neck or actually snap. If they don't snap you can pull the stud bolts out of the crankcase! Refer to one of the enclosed photos (not my engine!!). Even if you do not pull out threads or snap a bolt/sleeve nut, the forward right stud bolt boss can be extensively damaged (disclaimer again: not my work!)

Keep the rubber side down!
Bjørn