Hello again,
The threads on my crank shaft need cleaning up. I’ve measured as best I can and reckon M12 x 1.25mm generator side and x1mm other side.
I’m surprised the threads seem different and am doubting my findings.
Can anyone confirm?
Thank you!
Mike


 

Yeah trouble with mine too lol--but anyway--right side is always finer than mag side. Cheers from NZ.
Start again--if the thread is damaged & ya don't have a die. Can you get away with tapering off a few threads so you can get the nut started. I've luckily got spare nuts [lucky me] & on the right side i can put a few hacksaw grooves in the nut thread & sort of use it as a cheapy thread cleaneruperer. With the mag side we had an adjustable jaw die at work & could set it past the damage & wind it off which generally worked to fix it so usable. Mag side is normally a long thread so have a bit to play with. Other side no so much to spare.

Thanks for that… good to hear I wasn’t off the mark with different thread pitches.
I’ve got m12 x1.75, 1.5 and 1.25 taps and dies for cleaning threads
I was running the 1.25 tap through the generator nut. Went in easily for first 5mm or so then got tight. And now it won’t start on crank thread at all.
I can buy new nuts.. that’s no problem.
What I don’t want to do is use the wrong die on the crank shaft and totally mess it up!
The crank is going to be rebuilt at an engineering shop, I will ask them to clean up the threads… unless I can get a definitive answer on the pitch.
Thanks.
Mike

Better wait untill someone with more uptodate info chimes in before forcing things. Can ya lay the tap along the mag thread on the shaft to see how it relates.

My parts supplier advises the following, which is consistent with my measurements and comparison with my taps:
Crank thread R/H: M12 x 1.00mm pitch
 Crank thread L/H: M12 x 1.25mm pitch.
We strongly advise that you check the crank first before cleaning the tread to ensure that these measurements match the crank.


 

I can confirm flywheel nut is 12mm x 1.25.