Copper Head Gasket Torque?

[motovate]

I did a search figuring It would be an easy find because the copper head gaskets have been around for awhile but didn't find anything.

Anyone using the higher compression copper head gasket that is .010 thick find that they need more then the 170 inch/14 ft lbs torque for a stock .020 aluminum head gasket????

Thanks.

LBM

[michael_perrett]

I use a .010" copper head gasket on my Suzuki TM 250 head conversion to Hodaka 250 SL. I use the standard 250SL torque specs for it.

Mike Perrett

[Bullfrog]

I don't think the change to the copper head gasket (alone) requires a torque specification change. That being said, Harry Taylor tested and adopted a new (higher) "standard" torque specification for the 125cc Hodaka engines long ago. I've adapted his specification (yes, "adapted", not "adopted") and now use 250 inch-pounds for the head nuts on the 125 engines. I would recommend that specification for all "regular" sorts of 125cc Hodaka engines and riders. Hot shoe racers with well tweaked engines might like Harry's specification of 300 inch-pounds.
Ed

[motovate]

Thanks - I guess it would of helped if I pointed out I was going to use one on a 01 Dirt squirt. Not sure if the head studs are the same size as the 125's.

I have an old but lightly used bar arm style inch pound torque wrench that reads in 25 inch pound increments so I would probably go to 175 on it any way as the stock settting. Wondering if maybe in the 200 inch lbs might be bit better. Or if the studs are essentially the came as the 125 go to the 250 range.

Any thoughts ?

LBM

[motovate]

OK - I looked at the schematics for the 01 and the 94A. Both show M8 which I take to be an 8 mm stud. So the higher torque in the 200 to 250 inch pound range should be fine - - - - - unless the case thickness where the studs go into is a lot different and would tend to pull the studs out of the case at the higher torques on the 100cc case.

Anyone ever compare the late 100cc cases to the 125 cases where the studs go??

I'm looking for tight enough and not to pull the studs out of the case.

Thanks.

LBM

[Bullfrog]

I didn't think about the model 99, 01 and 02 engines in the previous comment. They the have larger studs and head nuts common to the 125cc engines . . . and can be torqued to 250 inch-pounds also.
Ed

[motovate]

Outstanding! Thanks

LBM

[dcooke007]

And one additional tid bit to head bolt torque. Always re-check torque after a couple of heat cycles. Most head bolts will be a bit looser after a bit of run time.

Danny Cooke

[motovate]

Thanks Danny that's a good idea.

LBM