MKIII Kickstart assembly rebuild

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p400

p400

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I am looking at renewing a 1975 MKIII kick start mechanism, as it is wonky, loose and hitting the master cylinder. I see the parts diagram and it seems all parts available.
I would like to leave gearbox in place, take out minimal parts, replace bushings/seals where practical, gaskets.

Is there a utube (without um, er, and shaky camera) to walk thru this ?
Maybe a written pictorial article?

This worn kick start has got to be a common problem.

MKIII Kickstart assembly rebuildMKIII Kickstart assembly rebuild
 
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Your plan of action covers a lot of ground. If the K/S arm is loose, and the splines on the arm and input shaft are serviceable than removing one tooth on each side of the pinch bolt bore and using a new bolt may just snug everything up ducky.

BTW the Mk3 K/S pinch bolt should have a thin head, about 1/2 the thickness of a standard 3/8-24 x 1 & 1/4" bolt, this keeps the fastener from tearing up the bellows on the rear master cylinder.

If you really want to replace everything associated with the K/S mechanism, it can be done without removing the g/b shell from the frame.

Also, and more apropos, checking the layshaft bearing, and NOT seeing the word Portugal on the outer race. There are volumes written about the side effects of NOT replacing that bearing, but the box should come out to effect that service.

Regarding Youtube Norton videos; there is a guy that drinks a lot of beer and uses the least appropriate tools for everything, entertaining for sure, an example of what not to do, definitely.

Best wishes
 
If the splines are worn on the kickstart shaft, you may need to replace it as well as the kick start lever. I wrecked a new lever by constantly re tightening the bolt which would never ever hold fast. Even using loctite. You sometimes have to bite the bullet for both. YMMV
Cheers,
Thomas
 
Sometimes the kickstart lever can be tightened on the kickstarter shaft splines by increasing the pinch gap on the kick lever.Remove kickstart lever and mount in vice (use some form of protection to not damage finish to chrome) with the pinch gap positioned so that a hacksaw can be run thru the gap.The hacksaw frame will need two blades mounted side by side.A selection of 2 X different blade TPIs is usefull . Then carefully run the said blades thru the existing gap and so increase the gap.Use different blade TPIs to gradually increase gap. The Kickstarter should now be refitted and should tighten up like when bike was much younger.A new high quality, higher grade bolt will also help as the threads in the kickstart and the threads on the bolt will be stretched and worn.This worked for my 850 MkIIA .
 
I have not opened this MKIII gearbox yet, but I am concerned about the kick lever stop. It appears this kick lever has been wearing against the rear master cylinder...…..and the reason is the lever seems to return too close to vertical. I see the sales lit shows the kick lever resting at about a 45 deg angle.

what stops the shaft/lever at the return position?
Is it shaft #32 hitting a stop in case #1?

MKIII Kickstart assembly rebuild
 
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