Threads in brake and clutch levers

[Gearbox]

Just wondering what thread should be in a Rocket Gold star levers. I have some new cables that have cycle threads and they don't fit. Assume they are after market.
Would it be safe to assume that A10's should have cycle?
Thanks

[RDfella]

Depends on who made the levers - unlikely now to be original. If it were me, I'd try a BSF bolt. If that didn't fit, a metric one (both coarse and fine - the latter is quite popular on japanese made stuff). After that, it's BA, UNF until you find what fits. 

[chaterlea25]

Hi gearbox
Post some photos of the components involved as your question is too vague

John

[Gearbox]

Thanks for the replies.
Basically, I have a new set of cables for my mongrel machine. (Gold star with the engine replaced by a super rocket unit, but to RGS spec) The new front brake cable adjusters are cycle threads on both ends. One end fits my 190mm twin leading shoe brake and the other end does not fit the handlebar control. The previous cable had split adjuster screwed onto the handlebar end and has a coarser thread. I am assuming these are aftermarket handle bar levers and wondered if the originals would have had cycle threads as per my new cables. If so, then I will replace them with suitable controls. 
Hoping Autocycle Engineering can help here

[Rex]

The adjusters at the hub end I've always found to be 5/16 BSCy but as you say, the handlebar end is usually a coarser thread, and dependant on the age/country of origin of the levers. Some later crappy repro items have a metric thread here.

[Gearbox]

Had a bit more time tonight. Looks like I have crappy repro levers, as they have an 8mm thread. Fortunately, my brother is going to modify the old cable fittings so that they will work untill I can get the proper items.
Still like confirmation as to what thread was in the original equipment.
Cheers
Seamus

[jjbsa]

It's a shame the makers of the repro levers didn't use an 8mm fine thread as its pitch is 1mm (25.4tpi) and a 5/16" cycle threaded adjuster would have gone in, maybe with a cycle thread tap needed to get clearance on the long length of thread inside the adjusters.  Goldies with clip-ons had welded on lever supports that had 5/16 Cycle thread in the lugs (I've just checked).  You can get cables that fit these from George Prew, Address: Mill House, Royston Road, Barkway, Royston, SG8 8BX, Phone: +44 (0)1763 848763  George tries very hard for authenticity in what he sells.  He has a passion for Rocket Goldies (as I do).  George's web site seems to have gone so perhaps he is winding down his operation.

The pivot bolts used by BSA on the levers were 0 BA (6mm x 1mm pitch, same as nnormal ISO metric apart from the angle of the thread groove) when BSA made the bikes, but now 1/4 inch bolts seem to be supplied.
I hope that helps,
Jon

[JulianS]

The original pivots were 1/4 x 26 tpi.

See below from 1958.