BSA Owners' Club Workshop Discussions

The BSA Workshop => Twins => Topic started by: MrShifta on 06 Sep, 2023, 21:14

Title: A10 head info reqd please.
Post by: MrShifta on 06 Sep, 2023, 21:14
Hi lads, I have bought the missing engine from the project I bought last year. I had already built an  other engine and sold the bike.  I now have the makings of a spare engine along with a twin carb aluminium head as well as the cast iron one. 
Question is do I build it with the ally head or use the iron one and sell the ally head and what bike is the twin carb head for.
The cases are just DA10 **** although the timing cover has the rev counter drive on it.  I suspect the owner was trying to make a replica RR or SR engine.

Ideas anyone ?
Title: Re: A10 head info reqd please.
Post by: LIONELSMITH on 11 Sep, 2023, 16:41
It was the Road Rocket that had the Alloy cylinder head with an inlet manifold separate to the cylinder head, enabling twin carburettors to be fitted.. So it could be a genuine RR engine. That is worth checking.
Title: Re: A10 head info reqd please.
Post by: JulianS on 12 Sep, 2023, 08:48
Lots of information on A10 heads here.

http://atlanticgreen.com/a10dph.htm

The earlier Road Rocket and Shooting Star heads had a detachable manifold for the single carb, around start of 1956 the head casting was changed to a cast in manifold for single carbs.

There were some after market manifolds made for the earlier heads to allow twin carbs to be used.