Author Topic: Blown cylinder head gasket and duff wrench  (Read 4052 times)

Online bsa-bill

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Re: Blown cylinder head gasket and duff wrench
« Reply #30 on: 06.08. 2020 09:49 »
Quote
One of the reasons why deflecting beam wrenches tend to stay in calibration much better than the micrometer adjustment type is defecting beam wrenches are never left with a load on the torsion bar.

fully agree
All the best - Bill
1961 Flash - stock, reliable, steady, fantastic for shopping
1959 Rocket Gold Flash - blinged and tarted up  would have seizure if taken to  Tesco

Offline Scott and Jay

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Re: Blown cylinder head gasket and duff wrench
« Reply #31 on: 07.08. 2020 05:27 »
Yes, I now turn mine down again - after each use. I was given my torque wrench by my brother. I took it to our local classic-bike-enthusiast engineer, when he was doing something else for me. He's a brilliant guy that makes our hobby all the more enjoyable. He said mine is an standard-quality click-type. He had a top-of-the-line one, with perfect calibration. He put a socket on his - to match mine, facing it (must have been a 3/16). He set them both to the same foot-lbs, then turned them against each other. The clicks weren't simultaneous, but very close. He did it again, at another setting - and the same closeness resulted. That was enough to judge mine "close enough"...

Offline bikerboy

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Re: Blown cylinder head gasket and duff wrench
« Reply #32 on: 26.09. 2020 14:58 »
Old school for me I am afraid, I do it by feel. IMO the only thing my TW does is check that the bolts are done up evenly.

If my TW clicks too soon and I dont think its tight enough I wind it up a bit more until I personally am happy that its tight enough.

Just to be particularly annoying to some, I have never retorqued a head in my life on an A10 and have owned them for at least 49 years, I will add that I have never blown a head gasket either.

All of mine have alloy heads and I do them up then leave them overnight. I check them again the next day and then whack the rocker box on, job done IMO.

Just make sure the head surface is flat, always use a properly annealed solid copper gasket and make sure the threads are perfectly clean before trying to fit the head. I will admit most of my bikes only do 2 to 3 thousand miles a year but thats only because I have 6 of them and normally try to use them alternatively.


BSA A10 x 4
BSA A65 Lightning
Triumph T150v
Tribsa (A10 frame 750 Bonnie motor)