Re- torqing Head

[SP10mk11]

Hello i am going to re-torque the head on my Z1R tomorrow any tips on this or is it all straightforward, ie loosen off nuts in sequence and retighten?

Cheers
Gary

[Pigford]

NO, don't loosen them, just re-torque 'em as they probably work loose, due to the gaskets settling down, usually after a couple of hundred miles

[SP10mk11]

Ok thanks very much for that.



Gary

[hanskloss]

I've just done first 150 miles on new 1075 Wisecos, I suppose retorquing should be done on COLD engine, but better ask ?

[Pigford]

I've just done first 150 miles on new 1075 Wisecos, I suppose retorquing should be done on COLD engine, but better ask ?

Yes, let it cool off first

[hanskloss]

thanks Pigford, not a long wait for an answer at all off to the garage now

[Ginger Bear]

When I had my bike on the Dyno at Debbens last year, Steve said that he 'backs off' each nut, then re-torques. One at a time............

[Pigford]

When I had my bike on the Dyno at Debbens last year, Steve said that he 'backs off' each nut, then re-torques. One at a time............

Ahhh, one at a time is the key - don't undo all together, then re-do

[zed1015]

Build engine, Torque head.

Run engine nice and hot . Leave to cool overnight, Re-torque cold next day.

Re-torque in proper sequence after 500 miles ( no mucking about slackening the nuts , just re-torque)

Has worked for me for 40 years. Job done.

[Taffus]

this thread is all torque.....


I'll get me coat.....

[Pigford]

this thread is all torque..... I'll get me STRAIGHT-JACKET .....

See yer in Dutschland lad

[Garn 1]

I hope you haven't been lead up down the garden path or "screwed".
We have a problem.... too many methods of re-torquing?

I have often gone to re-torque after a period of, say, 200-300km, when engine has cooled, and found the original torque must be exceeded to move the nut at all. I marked the position of one nut, then backed it off, only to find I may get a extra angular movement at the same torque setting.

Hence, I'm of the opinion that, we may have to back off one by one, when re-torquing!
RegardZ.

[hanskloss]

done it today without backing off, only 3 nuts moved slightly, will check again at about 800 km, Garn's idea of marking the nuts makes sense might try backing off than, thanks

[Pigford]

done it today without backing off, only 3 nuts moved slightly, will check again at about 800 km, Garn's idea of marking the nuts makes sense might try backing off than, thanks

QUICK NOTE: Most important is to ensure threads are clean & lubricated so the REAL torque value is set.... If threads are dirty, the torque value is only the effort to over come the friction caused by the dirt - not the actual full resistance to compressing the head tight

Also make sure there's enough thread & room so the cap nut doesn't hit the top of the stud before the head is compressed fully!!!

I'd not get too worried, unless your Torque Wrench has recently been calibrated, it won't even be within the manual stated "range"

[hanskloss]

good point Pigford, threads were cleaned and lubed with moly grease, as to the stud's being too short - haven't thought about this, could they stretch that long? I thought about calibration before starting the build, but as my wrench was only used couple of times I had it first compared against brand new one and it was spot on, so left it as is.