Torque setting - crank compensating and dynamo nut

Information relating to the Matchless G80 or AJS Model 18 500cc Heavyweight.
StephenG80
Posts: 264
Joined: Sun Apr 30, 2017 10:42 pm
Location: ARGYLL UK

Torque setting - crank compensating and dynamo nut

Post by StephenG80 »

Hi - just re-building my primary drive side and got stuck at the following points.

i. What torque should the nut holding the compensating shock assembly on to the end of the crank be or is the approach just to lock the system up (ie in gear and have someone sit over the back wheel) and tighten until tight ie common sense.

ii. What torque should the dynamo sprocket retaining nut be tightened to or is it the same approach as for the crank nut? ie lock it all up and just use common sense?

last question - in the manual it refers to a retaining ring for the dynamo nut but there no machined groove for one? (may be I miss-read it)

Any advice gratefully received ASAP as I hope to get her on the road for tomorrow and its due to be sunny!!!! :beer:

Stephen
User avatar
ajscomboman
Member
Posts: 3963
Joined: Mon Jan 01, 1990 12:00 am
Location: HAMPSHIRE UK

Re: Torque setting - crank compensating and dynamo nut

Post by ajscomboman »

Answer to questions 1 and 2 is, Yes! And the original dynamo nut did have a groove machined into it. I have a spare somewhere and I'll load a piccie when I find it, unless someone beats me to it.
User avatar
Duncan
Member
Posts: 2118
Joined: Thu Jul 10, 2003 1:00 am
Location: HAMPSHIRE UK

Re: Torque setting - crank compensating and dynamo nut

Post by Duncan »

Stephen, I would say common sense unless someone can give an authoritative answer.

Your nut should look like this:
STD-611.PNG
The picture on the spares scheme looks wrong is this the nut you have?
You do not have the required permissions to view the files attached to this post.
User avatar
ajscomboman
Member
Posts: 3963
Joined: Mon Jan 01, 1990 12:00 am
Location: HAMPSHIRE UK

Re: Torque setting - crank compensating and dynamo nut

Post by ajscomboman »

The spares service sell a modified nut which is nothing like the original.
StephenG80
Posts: 264
Joined: Sun Apr 30, 2017 10:42 pm
Location: ARGYLL UK

Re: Torque setting - crank compensating and dynamo nut

Post by StephenG80 »

Thanks folks. The nut holding on the dynamo sprocket is just an ordinary nut, no groove machined into it. I put a new WR key in and it has nipped up very snuggle on the taper, so I don't think it is going to go anywhere!

The lock washer from the spare scheme for the clutch hub nut was really thick. If I hadn't scored it with a coal chisel and pre-bent it a bit before putting it on, there is no way I would been able to bend it up in situ - is that normal?
User avatar
1608
Member
Posts: 2493
Joined: Mon Oct 05, 2009 1:00 am
Location: ESSEX UK

Re: Torque setting - crank compensating and dynamo nut

Post by 1608 »

As far as I recall there is no lock washer for the clutch centre, just a thick spring washer.
User avatar
dave16mct
Member
Posts: 3234
Joined: Mon Jan 01, 1990 12:00 am
Location: LANCASHIRE UK

Re: Torque setting - crank compensating and dynamo nut

Post by dave16mct »

It depends which clutch it is. AMC had a spring washer. Burman had a locking plate which went over a clutch stud and bent up on the nut. I always have trouble bending that.
Make sure you fit a locking device on the dynamo nut or it will come off, fall onto your primary chain, go round and fix itself onto the clutch sprocket and probabely bend the gearbox mainshaft at the very least! :roll:
Dave.
SPRIDDLER
Member
Posts: 8542
Joined: Wed Sep 01, 2004 1:00 am
Location: WEST SUSSEX UK

Re: Torque setting - crank compensating and dynamo nut

Post by SPRIDDLER »

Stephen G80 wrote: last question - in the manual it refers to a retaining ring for the dynamo nut but there no machined groove for one? (may be I miss-read it)
Image

This is the original dynamo nut, lock washer and circlip ('Ring').
'There is a tide in the affairs of men
Which taken at the flood............'
User avatar
Duncan
Member
Posts: 2118
Joined: Thu Jul 10, 2003 1:00 am
Location: HAMPSHIRE UK

Re: Torque setting - crank compensating and dynamo nut

Post by Duncan »

The spares service sell a modified nut which is nothing like the original.
000611.PNG
I cant see how this would lock, could you explain?
You do not have the required permissions to view the files attached to this post.
User avatar
robcurrie
Member
Posts: 957
Joined: Fri Dec 09, 2011 5:33 pm
Location: Limpopo SOUTH AFRICA
Contact:

Re: Torque setting - crank compensating and dynamo nut

Post by robcurrie »

Either the picture is of a wrong nut, or the nut has been manufactured incorrectly


Rob C
Locked