Clutch Drag

gortnipper

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On my mk2 I get 3.17mm/0.125".

Have you checked the clutch operating lever and cable end nipple via the tranny inpection cover?

As an aside, I bought a Venhill cable for UK bars a few years ago and the sheath was cut a bit too short, making the adjuster all the way out like yours.
 
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As an aside, I bought a Venhill cable for UK bars a few years ago and the sheath was cut a bit too short, making the adjuster all the way out like yours.
That is just one of the things I am considering.

Who supplied you with the correct cable length?
 

gortnipper

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That is just one of the things I am considering.

Who supplied you with the correct cable length?
It wasnt enough that it impaired the cable pull so that it resulted in your symptoms, so i left it.

Did you check inside tranny?
 
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Did you check inside tranny?
The primary is together and again in the manual the clutch rod should be around 244 mm mine is 249 mm which can only be good in this case.

First I will fit the old cable as a reference. The operating arm is securely placed and correct and if this helps no further then it will be of with the gearbox lid for a peer inside.
 
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think 249mm is correct for a Commando.
One more problem solved thank you!

From the middle of the cable drum to the beginning of the sheath on the clutch cable according to AN should be
89 mm mine is not far off with 92 mm.
 

gortnipper

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One more problem solved thank you!

From the middle of the cable drum to the beginning of the sheath on the clutch cable according to AN should be
89 mm mine is not far off with 92 mm.
Cable length correct?
 

L.A.B.

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From the middle of the cable drum to the beginning of the sheath on the clutch cable according to AN should be
89 mm mine is not far off with 92 mm.
What is the clutch lever pivot radius (pivot to nipple centres) and when adjusted how much cable travel?
 

concours

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"pushrod and thought I smelt GB oil on the adjuster face. "

Push
Rod
Seal
(as mentioned above)

gear oil will make the clutch drag.
 
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Woody850 said:
Could the clutch rod seal screwed onto the end of the mainshaft be of disturbance?

Pull the clutch adjuster screw completely out of the diaphragm cup.
Look inside and "my" (DD/AGTS) CCRS will have about .1" sticking out beyond the CCRS when pushed in ALL the way and seats the 1/2" ball against the release cam.
For the test the cable must be loose.

Added:
To disengage the clutch the following observations can be made. The clutch carrier is pushed out .035" than the clutch starts to disengage. At this point the high fingers have been well lifted and the low fingers are now just starting to lift off of the clutch pressure plate. By .050" lift both sets of fingers are free and clear of the clutch pressure plate and the clutch should have almost no engaging properties.
 
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What is the clutch lever pivot radius (pivot to nipple centres) and when adjusted how much cable travel?
The pivot radius from centre to centre is 27 mm while the pull
taken from between mounting and lever at the maximum is
13.5 mm.

The lever in itself has in it's pivot hole become oval despite the
insert (one has been ordered).

Now yesterday I set the clutch centre screw at 1/3 out while
(the purists won't like me for this) on the cable as it enters the gearbox I lay two small 1mm thick washers to lengthen the sheath. Gear change was fine but neutral seemed not as positive as I am used to, it just felt like there could be a bit more pull.

DynoDave's excellent instructions gave me peace of thought that all is well in the primary and gearbox. Pity you weren't around when the manual's were being written.
 
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13.5mm seems low. My Mk3 it's about 19mm.
I really don't know, 19 mm is a lot. Comparing the lever mounting to my T140V they are both identical only the pressed steel lever gives more pull.

Having repositioned the mount on the bar it is possible to win maybe a mm or two.

Andover Norton show the same part
CLUTCH LEVER MOUNTING (06.3374)
for both Triumph and Norton although painted black so I don't think mine was replaced with the wrong part.
 

L.A.B.

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I really don't know, 19 mm is a lot.
My Mk3 has standard lever parts. As your clutch has an inadequate lift at the pushrod/spring then only having 13.5mm cable pull at the lever would seem to be the reason why.

Andover Norton show the same part
CLUTCH LEVER MOUNTING (06.3374)
for both Triumph and Norton although painted black so I don't think mine was replaced with the wrong part.


The clutch pivot in AN's photo is the 063678 extended pivot casting (above) which is correct for '73 -'74 Commandos such as yours but is not the same part as previous 063374 (black) or 063372 (alloy, below). The 063678 extended pivot casting wasn't used on Triumphs.




Edit: Yet another AN parts error the '73 - '74 Norton pivot is listed as the individual part but the correct pivot as part of the '71 - '72 and Triumph switch cluster assembly.

 
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cable pull at the lever would seem to be the reason why
I had been staring the problem head on in the mirror and couldn't see the reflection. I would buy you a beer with a nip (shot of whisky) to go with it LAB.
Obviously it was a quick fix by an earlier owner of my bike and at this point has it reared its ugly head.

Many thanks for all the help I have received.
 

L.A.B.

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:)

There were three versions of alloy Commando clutch lever.

062249 ('71)
062702 ('72 - '74 and replaces 062249)
065878 (850 Mk3).
 
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My Mk3 has standard lever parts. As your clutch has an inadequate lift at the pushrod/spring then only having 13.5mm cable pull at the lever would seem to be the reason why.
I am baffled as to why 12.5mm of cable pull is inadequate. That represents the WHOLE cam profile shown here of .500". That is 2-1/2 times the pull required to make the clutch disconnect.
131" is full travel clutch movement of which only .050" should be required to give complete clutch disengagement. What kind of gearbox shifter mechanism maintenance or work has been recently done... or NOT been performed that is being overlooked.... just thinking out loud?

If there is no glued up plates, over tight chains, or notched clutch hub then is should shift like a swiss watch...IF...the gearbox is good.

FWIW
My cable measurements were cable movement at the gearbox. Therefore I did not consider bowden cable contraction which removes some cable pull effectiveness.;)

Added: we seem to have moved from clutch drag to hard to find neutral as the residual symptom
 
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