Hitchcocks Forum

Quick question on head fixing torque values with composite head gaskets.

24 ft/lbs seems to be the normal figure, should I be using the same with a composite gasket?

Also do I need to re torque the head back down after running the bike as with a copper gasket, if so should it be after a set distance, or just bring the engine up to running temp allow to cool and then re torque ?

Hi Andy, I assume you are talking about the Classic engine Bullet. If so, I believe the torque value for the head studs is listed at 24 ft/lbs in the manual, I feel this is on the high side so have always gone slightly under that at 22 ft/lbs but that is just my preference.



The composite gaskets should still be re torqued and this is always the practice I have followed. I get the bike up to temperature and then allow it to cool fully before re torquing, usually leaving it for the next day. I would usually just go for a short ride (5 miles or so) but expect there would be no difference if it was just warmed up on the stand or a 30 mile ride, just make sure it gets up to temperature.

Dan

Do you recommend re-torquing after one run immediately following installation, or after say 500 miles? Or maybe both?

In my opinion, there is no immediate rush to re torque the head after the first run if its not convenient to do so. If you end up doing a few runs before getting round to re torquing, that should be just fine. I personally would want to try and get this done within the first 50 miles or so, instead of letting it build up to 500 miles without being re torqued.



You do hear of people re torquing a second time later on down the line, say 500 miles or so, but for me, its not something I have ever found the need to do.

I was advised that the composite gasket did not need retorquing so I didn't. It's been ok for 5000 mls so far. I used 21 ft/lds.