Thread restoration - front wheel bearing lock ring

[Douglass Harroun]

Routine tire change turned into a nightmare. Pulled off the old, worn tire, thought the bearings might need grease, consulted the original factory manual, clearly states the lock ring is LEFT hand thread, proceed with pin wrench- no go, then light punch and hammer, then harder. Tried heat gun. My god, why is this thread so stuck? Did we read the manual correctly? Yep. Then opened a Haynes, then a reprint manual. They state it is RIGHT hand thread! Finally got the lock ring out with combination of dremel cutting wheel and punch, hours of work, bearings required slidehammer with special lip-edge fitting. Now have to restore some damaged areas in the threaded area of the aluminum hub. Now looking for a thread file. Probably does not need to be special Whitworth or cycle thread , just 20 TPI.
Doug

 

[Nater_Potater]

Then opened a Haynes, then a reprint manual. They state it is RIGHT hand thread! Finally got the lock ring out with combination of dremel cutting wheel and punch, hours of work, bearings required slidehammer with special lip-edge fitting. Now have to restore some damaged areas in the threaded area of the aluminum hub. Now looking for a thread file. Probably does not need to be special Whitworth or cycle thread , just 20 TPI.

So, did it turn out to be right-hand thread after all?

 

[kommando]

A 1/4 UNC tap die is 20 tpi and can be used to clean up cycle 20 tpi threads used as a hand tool as long as there are some good threads left, if you get the plug version is is nearly full diameter to the end. Just used one to clean up an axle with the end thread distorted.

 

[Stephen Hill]

The locking ring, at that large diameter, is unlikely to be a CEI thread. According to the CEI thread table, the only diameter that is 20 TPI is 5/8". But your advice to use a bottoming tap as a thread scraper is sound, assuming you could match it to the threads on the hub.
http://www.motalia.com/Html/Charts/cycle_chart.html

Stephen Hill

 

[kommando]

That chart is missing a bit of detail, 20 tpi was an option on cycle on 7/16 and above so any large dia item could be 20 tpi.

 

[L.A.B.]

So, did it turn out to be right-hand thread after all?

As a rule, lock rings on the left side of a wheel are generally right hand thread, and those on the right side are left hand thread as then they shouldn't be unscrewed by the wheel rotation if they become loose.
Unfortunately some versions of the factory manual say "left hand thread" when it is right hand (and some versions of the 850 MkIII manual also give the wrong information for the rear wheel lockring which is on the left side so is right hand thread).