1958 cyclone rebuild

[John M]

Hi. I have an engine case set from 1958 but the crankshaft is a bolt up suggesting it is not the original or one I should use. The fit feels unhappy and snags on the casing when rotated.
What is the best crank to use here? Will a large bearing crank fit or should I stick to safe. Original spec is favourite all along here.
Any thoughts?0

View of crank

P S Wanted Huntmaster 1958 monks hood headlight surround ]

[nevhunter]

It would be good practice to have any crank you use crack tested. Snagging isn't the end. Find where and machine a bit off and rebalance. Clean oilways carefully also before reassembly. Nev

[Roger Gwynn]

All FH cranks have a bolt on flywheel. 1958 would originally have had the large journal crank, hard to find as everyone wants one but unless you tune or ride it really hard there is no problem with the small journal. Usually the snagging problem is with the large journal rods, but I would remove a bit of metal from the case to clear rather than the crank as it won't be much.

[simon.holyfield]

All FH cranks have a bolt on flywheel. 1958 would originally have had the large journal crank, hard to find as everyone wants one but unless you tune or ride it really hard there is no problem with the small journal.

Some nice people in Bungay found one for me. None left?

[Mick D]

The fit feels unhappy and snags on the casing when rotated.

Hi

Have you set the end float correctly? my 58 FH crank case showed signs of historic contact with it's large journal crank, but after shimming there was none

Flywheel Contact.png (207.58 KiB) Viewed 352 times

Regards Mick

[John M]

Thank you for your helpful replies everyone.