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Re- torqing Head
Posted: Mon May 21, 2007 6:05 pm
Author: 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
Posted: Mon May 21, 2007 6:40 pm
Author: 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

Posted: Mon May 21, 2007 7:22 pm
Author: SP10mk11
Ok thanks very much for that.
Gary
Posted: Sat Jun 30, 2012 8:12 am
Author: hanskloss
I've just done first 150 miles on new 1075 Wisecos, I suppose retorquing should be done on COLD engine, but better ask ?
Posted: Sat Jun 30, 2012 8:13 am
Author: Pigford
hanskloss wrote: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

Posted: Sat Jun 30, 2012 8:50 am
Author: hanskloss
thanks Pigford, not a long wait for an answer at all

off to the garage now
Posted: Sat Jun 30, 2012 9:15 am
Author: 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............
Posted: Sat Jun 30, 2012 4:35 pm
Author: Pigford
Ginger Bear wrote: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

Posted: Sat Jun 30, 2012 5:26 pm
Author: 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.
Posted: Sat Jun 30, 2012 5:37 pm
Author: Taffus
this thread is all torque.....
I'll get me coat.....

Posted: Sat Jun 30, 2012 6:38 pm
Author: Pigford
Taffus wrote:this thread is all torque..... I'll get me
STRAIGHT-JACKET .....

See yer in Dutschland lad

Posted: Sat Jun 30, 2012 8:41 pm
Author: 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.
Posted: Sat Jun 30, 2012 8:58 pm
Author: 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
Posted: Sun Jul 01, 2012 8:37 am
Author: Pigford
hanskloss wrote: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"

Posted: Sun Jul 01, 2012 9:02 am
Author: 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.