G'day HWM.
BSA Service Sheet 208 from October1948 (reprinted June1966) recommends 10ft/lbs for early 22TPI BSF Bolts. By early, we reckon this refers to the Longstroke Bolt, together with Steel Conrods.
A later 26TPI Cycle Thread (CEI) bolt is specified to 8.5 ft/lbs, and this bolt with its nut can supposedly be substituted for the earlier BSF bolt and nut. The torque setting was raised to 22ft/lbs in 1956, but this may be because of the use of self locking rather than castle nuts and split pins. These are the bolts used with the more familiar alloy rods.
So if anything, the scenario is confusing, as the service sheet only mentions early and later parts, rather than specific part numbers.
Maybe worth researching comparable figures for similar engines using steel conrods. I would have considered there is a fair degree of leeway as the steel rod is a much tougher component than the softie alloy rod. The Ford Engine would have steel rods, so I do not think the higher figure would distort the steel Longstroke Rod. Anyone else with experience of these rarer motors?
Sorry if this adds to the dilemma, but maybe a useful bit of background for your research.
I've got this to come, as I have an incomplete basket case Longstoke motor, and sourcing some of the missing bits is taking a fair time.
Swarfy
