Con rod and head bolt torque settings.

[Steve Slocombe]

Dear Ivor, correction coming, sorry. The VL head bolts are 9/16" AF but the shanks are 7/16". The calculation about cross section is still correct, in that 5/16" studs have half the cross section of 7/16" and so should take half the torque. Big ends should not be tight on assembly. Orientation is important, and the rods and caps should all be marked to help assembly. Check with the engine builder what torque was used on the cap bolts, and if it was under 30 that might solve your tightness issue.

[Ivor]

Thanks Steve, I just done the con rods at 30, and they were 5/16" (Bigger than I remember when I posted the question ) The only worry I've got there is that one of the big-ends is tight, and I'm not sure if it will just bed in ? The white metal specialists that did all the work on the crank sent the rods back to me loose but they said that they had assembled them and then taken them apart. I think the head bolts are 9/16", So I will see how 55-60 feels.

[Steve Slocombe]

Dear Ivor, I was told 25 pound feet on the rod cap bolts by my engine builder on a Henderson KJ. I have 5/16" diameter head studs on this I-o-e engine and was told 15 pound feet by my local old bike shop. I thought this was a bit low, as the 9/16" head bolts on the VLs get pulled down to 55-60 pound feet and a 5/16" stud has half the cross section, so ended up pulling them down to 20 pound feet, then going over again after the crush rings settled down. I'd be interested in what the Indian experts have to say.

[Ivor]

Does anyone know the torque settings for the head bolts and con rod end caps for a 1940 four ? It's the small con rod bolts that I don't want to over tighten and sheer off.