If you like our site, please consider joining our club!
By joining you will help ensure that we can continue to provide this service
JOIN HERE!

/2 flywheel bolt

Post Reply
mcsherry1328
Posts: 285
Joined: Fri Oct 27, 2006 3:00 am
Has thanked: 12 times
Been thanked: 3 times

/2 flywheel bolt

Post by mcsherry1328 »

Looking for the dimension of the flywheel bolt thread. The bolt diameter and the pitch. I want to buy a tap to clean threads on the crankshaft.

User avatar
jwonder
Posts: 784
Joined: Wed Nov 23, 2016 7:50 pm
Location: Long Island, New York
Has thanked: 3 times
Been thanked: 7 times
Contact:

Re: /2 flywheel bolt

Post by jwonder »

The /2 models had Slotted M8 x 1.0 pitch screws. They were 20mm long and are available on Salis here: https://bmwclassicmotorcycles.com/index ... 1210070155

There are 6.

So you would need an M8 x 1.0 pitch tap.
James Wonder
Vice President, Vintage BMW Motorcycle Owners
2022 BMW Friend Of the Marque
Long Island, New York

mcsherry1328
Posts: 285
Joined: Fri Oct 27, 2006 3:00 am
Has thanked: 12 times
Been thanked: 3 times

Re: /2 flywheel bolt

Post by mcsherry1328 »

Sorry, I didn't specify that I'm looking for the dimensions of the large flywheel bolt that secures the flywheel. The bolt is 18mm just looking for the pitch. Is this specific to BMW or should I be able to find a tap to fit crankshaft ?

User avatar
jwonder
Posts: 784
Joined: Wed Nov 23, 2016 7:50 pm
Location: Long Island, New York
Has thanked: 3 times
Been thanked: 7 times
Contact:

Re: /2 flywheel bolt

Post by jwonder »

Salis has them listed as M18 x 1.5.

I am not sure why you are doing this, but two things I would note:

1) if you do use a tap then I would use a bottoming tap. I would wonder if the threads on the bolt were pulled before the internal thread in the crank.

2) I would use a thread chaser versus a a tap as I would think you would not want to remove any material from the threads.

I would be interested in the reason for the tap for future note.

Hope this helps.
James Wonder
Vice President, Vintage BMW Motorcycle Owners
2022 BMW Friend Of the Marque
Long Island, New York

Post Reply