Head Re-torque Process

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45...click...done!



Last time around, one of the outer two 6mm bolts had that (just-too-much torque applied) feel, so I just snugged those. I can't imagine what good those two tiny bolts do anyhow.

On a fresh built motor or top end there should be no issues.
When initially torqueing the head it is done in several stages working up to the final figure and between each stage the nuts are stationary but don't need to be backed off to break any resistance.
When re-torqueing after the first run and cool down there is no need to back off.
After 500 miles just go round with the wrench and re-torque in sequence , no need to back off.
If you have corrosion on the studs/nuts at 500 miles then you don't use the bike enough.
500 miles can be covered in a day or two and at least within a week which is not enough time for stiction between mating parts to cause problems.
Once the head is at the correct torque there should be no reason to re-torque until the head has been off again unless the builder was incompetent and got it wrong in the first place
Hd nuts in conjunction with HD studs should be torqued to between 36 and 42 lb MAX.
Going to a higher torque has no advantage unless you want to strip the studs out of the cases.
You don't even need to go above standard factory torque specs unless you are running high compression or a turbo/supercharger etc.

Zed1015, what is your opinion of oil on studs and bolt flanges regarding torquing?
Also what about Moly Disulphate {Moly} on thread & nut flanges?
RegardZ.

zed1015 wrote: On a fresh built motor or top end there should be no issues.
When initially torqueing the head it is done in several stages working up to the final figure and between each stage the nuts are stationary but don't need to be backed off to break any resistance.
When re-torqueing after the first run and cool down there is no need to back off.
After 500 miles just go round with the wrench and re-torque in sequence , no need to back off.
If you have corrosion on the studs/nuts at 500 miles then you don't use the bike enough.
500 miles can be covered in a day or two and at least within a week which is not enough time for stiction between mating parts to cause problems.
Once the head is at the correct torque there should be no reason to re-torque until the head has been off again unless the builder was incompetent and got it wrong in the first place
Hd nuts in conjunction with HD studs should be torqued to between 36 and 42 lb MAX.
Going to a higher torque has no advantage unless you want to strip the studs out of the cases.
You don't even need to go above standard factory torque specs unless you are running high compression or a turbo/supercharger etc.

ZED1015, Knows his stuff!! He has been doing this on a Professional ( earning his Living) basis for a Long time.
I believe what he is saying is 100% CORRECT.
Regards

TennesseeZ Ed

Garn wrote: Zed1015, what is your opinion of oil on studs and bolt flanges regarding torquing?
Also what about Moly Disulphate {Moly} on thread & nut flanges?
RegardZ.

Good question...

Regarding the torque tables, the KZ650 Kawasaki Service Manual states:
"All these values are for use with dry solvent-cleaned threads."

It also states:
"When checking the tightening torque of the bolts and nuts, first loosen the bolt or nut by half a turn and then tighten to the specified torque."

Ed