AJS 1930 1000 cc v twin model S1/S2 discussed and Black Mountain test ride to check all is well. 

I recently rebuilt the engine in this machine, with rebored cylinders, new pistons and reground valves etc, but the owner reported it appeared to tighten up while pulling a sidecar with a passenger on board. I suspected it might just need running in as a solo for a couple of hundred miles first, so I tested it pulling up the Black Mountain in solo trim, as any tight running engines tend to complain going up there. As it happens, my only concerns were in regard of the rather worn [and oily] sidecar tug tyres which were fitted, but we managed the 30 mile round trip with no problems, although my camera battery let us down for the 50 mph 'blast' in the last mile or so on the way home. Both AJS and I lived to tell the tale, though, and that is the main thing!