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Heavy Clutch Operation

John Hudson. Roadholder No. 107 - Jan/Feb 1982

Recommendations for easing the load on your left hand

The AMC clutch withdrawal mechanism is designed to work with a handlebar lever which measures only 7/8" between centres of cable nipple and lever fulcrum screw. Levers with greater centres withdraw the clutch farther than is necessary with a corresponding increase in operating pressure.

The small operating lever in the clutch operating body must come up exactly in line with the cable entry in the gearbox outer cover. If it does not, then as the lever rises it tries to put a 'Z' in the inner wire and this is nearly always the cause of broken cables at the gearbox end.

The operating body is hardened and so is the ballrace against which it bears in the gearbox inner cover, but the lockring which secures it is soft and so as the ring is tightened, the body must 'creep' round with it, the soft ring gripping the hard body which easily moves against the hard ballrace.

Before removing the outer end cover, take out the cable and adjuster complete and make a small 'pop' mark on the top face of the inner cover exactly in transverse line with the centre of the cable entry hole in the outer cover.

On boxes other than Commando, removal of the inspection/filler cap makes it fairly easy to see if the lever is reasonably in line with the cable entry as it operates across the centre of the aperture but on the Commando this is not so easy as they had to put the cable entry further forward because of the position of the rear Isolastic mount, they did not move the position of the aperture.

On reassembling to put the lever in the right rotational position - hold it about 3/8" short of its correct position until the lockring begins to turn it. Now as ring and body turn together, they should come to a stop in the right position - check with a short steel rod or Allen key which will closely fit in the slot in the body to see that it lines up with the mark you have made on the inner cover. If the body has turned too far, slacken off and go back say 1/2" and try again. This can usually be done in 2 or 3 attempts at most.

One final point - with flat bars, almost all replacement cables will be too long and if one has soldering ability it is not too difficult to remove the nipple at the gearbox end, pull out the inner wire and shorten the outer until it fits properly. Leave the outer cable in position in the handlebar lever and put the bars to full left lock, then with the cable passing over the back of the oil tank (on Dommies), cut off whatever is necessary to allow the outer to enter the adjuster without being tight at any point.

 


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