Clutch Adjustment

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blipJC

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Can some one pleas tell me the exact procedure to adjust the clutch? My cable broke last year and when I fitted the new one it is stiff and has no "play" with no more adjustment available at the leaver. As soon as I apply the leaver the clutch disengages and won't engage until the end of the release stroke of the leaver The new cable is the same length as the one that broke and it appears that the cable is lined up with the arm and doesn't look like the arm has dropped. I have tried to loosen the adjuster nut on the primary side by hand but it just rotates the engine. I will try and nudge it with the impact gun and see if that breaks it loose. The owner and shop manual state to loosen the cable at the leaver but I have no more adjustment available and is at the max as is. Should I remove the cable when I get the nut loosened and then make the screw adjustment or adjust the screw with the cable installed? Any help is appreciated as I would like to be riding this weekend. Thanks.
 
BLIPJC,

Not a Norton whiz but this might help

Have you tried putting it in gear and using the rear brake to stop the turning of the clutch? I would get the adjuster nut undone before i tried anything else, leave the cable in.

What was the old cable like previous, was the play and release point of the lever different? Is the external length and the internal lenths the same as the old one?

Ross
 
Cable is the exact same as the broken one. It broke the solder at the leaver connection and I lost both parts to the leaver adjuster. I replaced them and that's the only thing different from the previous set up. The previous set up was adjusted correctly when I had the plates replaced at the beginning of last season and disengaged/engaged with ease. With the new cable it's very stiff at the leaver and the clutch disengages immediately. I did put it in gear and try to loosen the nut but didn't think to applied the break as it was late and was working alone. I will try that before I use the impact.
 
Have you checked the actuating lever at the end of the mainshaft, when changing a cable it can drop out of position.

It should look like this.

Clutch Adjustment
 
blipJC said:
I have tried to loosen the adjuster nut on the primary side by hand but it just rotates the engine. I will try and nudge it with the impact gun and see if that breaks it loose.
Click to expand...

The nut often needs to be shocked loose. Putting it in gear and holding it with the brake does not always work as the diaphragm spring can rotate within the clutch assembly.

blipJC said:
The owner and shop manual state to loosen the cable at the leaver but I have no more adjustment available and is at the max as is. Should I remove the cable when I get the nut loosened and then make the screw adjustment or adjust the screw with the cable installed? Any help is appreciated as I would like to be riding this weekend.
Click to expand...

Once you have slackened the nut and slackened off the adjuster (but not too far as the lifter can drop out of position) you should find play returns to the cable.

Pushrod adjustment must be done first, so screw the adjuster out until you begin to feel play in the clutch lifter (in the previous picture) then screw the adjuster in just far enough to remove the play from the lifter, then screw the adjuster out by a third to half a turn and lock it with the nut, then adjust the cable.
Note the manual says to unscrew the adjuster by one full turn, however that can be too much.
 
I recently had the same problem of my clutch turning whilst trying to undo the adjuster locknut & none of the suggestions worked (or were not feasible).

Eventually I used a dremel to 'relieve' the nut (after making sure that the open primary was well protected from any debris) & replaced with a spare (just watch out for the threads on the adjuster).

Regards

Mike

Mk III Commando
 
This morning I tried to slacken the clutch adjuster nut by hand w/ the bike in gear and brake applied. Would not budge. Pulled out the impact and was loose instantly w/ under 20 psi in the tank. As soon as I turned the adjuster screw I could see the cable slacken. I adjusted the screw and reversed 1 full turn tightend the nut and finished by adjusting at the leaver end. Now the clutch works like new. Once I check and topped up the fluids I was out riding in under an hour. I put on new premiers late last season and this year I didn't even have to tune them. 2 kicks and I was off. Thanks for all the help.
 
Okay, I admit I might be beating a dead horse here, but can someone explain the effect of turning the adjustment screw out (left) or in (right) has? I need to engage the clutch sooner than my current adjustment allows.
 
contours, gently turn the adjustment screw in until you feel it stop or seat then back it out 1/2 turn
that is the correct setting, tighten the set nut and check your handle bar gap to about a nickel width slack
 
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You want about a half turn of slack at the clutch pushrod adjuster nut. Otherwise , (too tight ) you could have it too tight against the push rod and hurt the hardened ends by having any forces on the push rod. The other scenario is too much slack at the clutch adjuster nut (1 or more turns out) and not achieve enough lift of the clutch diaphragm even after playing with the handle bar final adjuster. Once set you will finally settle on a bit of slack at the handle bar end to be sure there is no pressure on the clutch with full disengagement of the clutch lever.
 
1up3down said:
contours, gently turn the adjustment screw in until you feel it stop or seat then back it out 1/2 turn
that is the correct setting, tighten the set nut and check your handle bar gap to about a nickel width slack
Click to expand...
Thanks for the tip. My bike rolls when the clutch lever is pulled all the way. I have to assume that turning the screw to the left increases the slack in the cable. Then to gain more clutch I must turn it to the right.
 
My early bike is very critical to that clutch adjuster nut. I can only back it off about 1/8 a turn from contact or otherwise I get bad/heavy clutch action. I've tried different stack heights, but that didn't help. I never have figured it out, everything measures just like DynoDave's page. Your clutch lever should act like a compound bow, once you break over the diaphragm spring, it should be easy to hold. It's very noticeable on my bike.
 
1up3down said:
correct
Click to expand...

Thank you for the confirmation.

This problem has kept me off the bike all summer (due to lack of time mostly). It developed suddenly after a 25 mile ride. The clutch cable behaved as if it had stretched a few mm. After inspecting the back end of the cable I realized it had more to do with the rod adjustment.
 
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The clutch rod adjustment should be viewed akin to adjusting tappets. The room you leave there by turning the adjuster out a bit is to allow the rod to expand from heat without it putting tension on the diaphragm. If you form dimples on the end of your rod it is from this adjustment being too little. There is a photo somewhere of a rod with its ball bearing welded to the end from friction heat. Apparently from tightening down the adjuster in an attempt to get the clutch to operate more "fully". I would be inspecting the clutch plates and other aspects of this clutch before I started riding without any slack at the clutch rod.
 
Aditionally, I remember somewhere seeing that an Atlas actuating lever fits into the Commando but has a different ramp. I don't recall now what the effect of that different ramp is but it would be difficult to figure this one out without removing the actuating lever and comparing it to another. Does anybody remember? Is that part of the Mick Hemmings Gearbox DVD?
 
rvich said:
Aditionally, I remember somewhere seeing that an Atlas actuating lever fits into the Commando but has a different ramp. I don't recall now what the effect of that different ramp is but it would be difficult to figure this one out without removing the actuating lever and comparing it to another. Does anybody remember? Is that part of the Mick Hemmings Gearbox DVD?
Click to expand...
Yes I remember but never heard of someone who did it and made the switch-over and how the clutch action felt in comparison..
 
I followed the link provided by LAB and as a result also found a conversation about clutch rod length. What I am taking away from these two threads is that the clutch rod length combined with the ramp of the actuating lever could have a marked impact on clutch performance with very little change in actual dimension. For anyone having perpetual clutch problems it would seem that verifying these components would be worth the effort. It is pretty easy to pull the rod and look for dimples in the end. That would be one clue as to chronic adjustment issues.
 
rvich said:
I followed the link provided by LAB and as a result also found a conversation about clutch rod length. What I am taking away from these two threads is that the clutch rod length combined with the ramp of the actuating lever could have a marked impact on clutch performance with very little change in actual dimension. For anyone having perpetual clutch problems it would seem that verifying these components would be worth the effort. It is pretty easy to pull the rod and look for dimples in the end. That would be one clue as to chronic adjustment issues.
Click to expand...
Can't see that being a factor much. The push-rod ends are heat-hardened too . I've never seen one with "dimples"that could be interpreted as wearing out the length. I have 3 in my hand right now , all 3 have small dimples. And yes I'm a hoarder , just ask my wife. Enjoy.
 
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