Tighten the cylinder head

Pushrod Twin

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VOC Member
Remember when using your crows foot to do the calculation below, or cheat & use the torque wrench at right angles to the crows foot.
(Actual torque required) x (torque wrench length)
(Torque wrench length) + (Length of adaptor) = torque wrench reading to achieve actual torque on fastener

or you will over torque them. I know the crows foot is only 1 1/2 inches or so long, measure it for the calc, but it can be the difference between stripped threads or not. (Now that you have probably well finished & been riding the tail off it!! Oh, no, its cold there isnt it? Cheers, R:eek:
 
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Bracker1

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I am a bit confused. Once properly stretched a bolt should not have to be retorqued unless it has exceeded it's useful life and no longer holds.. Connecting rod bolts in autos are torqued once and left to run thousands of miles. Why not just get new head bolts and nuts not have to worry about retightening. 8 bolts can't be too much money. Thanks, Dan
 

Don Morris

Active Forum User
VOC Member
Hi Bracker1, yes you are quite correct, but do consider what you are clamping up. In the case of the big end its just solid steel.

In the case of a cylinder head/muff'/gasket these will all settle. Over time or heat cycle.
 

Bracker1

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Thanks, That will explain it. My bike is settled in for the winter, so I'll check this spring. Merry Christmas, Dan
 

Simon Dinsdale

VOC Machine Registrar
VOC Member
VOC Forum Moderator
Bracker1,
The problem with the head nuts needing re torqueing is the paper cylinder base gasket which can sometimes be too thick, compresses and so effectively reduces the the torque the nuts are tightened to. A couple of heat cycles over a few hundred miles settles the base gasket and then you can re-torque the head. Some people have used an o-ring in a grove machined in the bottom of the cylinder muff and eliminated the base gasket, but I don't know if this eliminates the problem of re-torqueing.
Cheers,
Simon.
 

mr.hutch

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VOC Member
Yes of course wonderful tools but they are very expensive, I own a 'snapon' screwdriver that cost 30£ fifteen years ago! was it realy worth it ?
In retrspect no, perhaps if I had been a professionel, then yes.
 
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