35mm fork tubes seem to my eye to come in two different threads at the top end -- the threads into which the fork caps screw. Of the two, the older seems somewhat finer pitch than the newer. Is this correct?

My question addresses mid-eighties 35mm fork tubes only.

 

Harley used two different manufacturers for fork tubes, showa and I cannot remember the other one. Although I never checked them it is possible they used different threads.

 

Thanks, I think I've figured it out.

Looks like they continued the old non-bushed narrow glide 35mm forks until late '86, then went to a different design with bronze bushings on the tubes during '88, also 35mm forks. Perhaps to prevent folks from mixing the parts, they apparently went to the coarse thread. Both the bushed and non bushed were Showa forks.

In '88, they went to a 39mm fork. Don't know who made it, but it too was probably Showa.

The upshot is that the caps for the coarse threaded, 35mm forks were produced for a fairly short time -- same is true for the fork tubes themselves.

If anyone knows differently, please let me know.