X9 125cc none EVO flywheel nut

[Mackay]

Hi all, help please am trying to work out what tightening torque I should use for the flywheel nut on my 2003 (non EVO I think) 125cc from what I can see the workshop manual states 54-60 nm (so 39.83 to 44.25 ft lbf)....does anyone know if that is correct???

My confusion is another table states 116 nm (85.56 ft lbf) but i think that is referring to a 250cc?? would the torque needed on a 125cc be almost half that needed on a 250cc

Am confused and want to get it right before I put the water pump etc back on the bike and put it all back together.....

[Dave Milnes]

54-60 is the figure given for the 125 in the official torques documentation. 116 is also given in the official workshop manual on one page and 54-60 on another page in the same book.
To apply greater than 100Nm the thread diameter should be at least M12. Could these conflicting figures be for something different. Are there other studs and nuts on the flywheel which the lower figure relates to?
The last thing you want is to strip the crankshaft threads!

[Mackay]

Ok...sorry.....really confused now.....

I have measured the diameter of the threaded shaft and, it's difficult to get it exact without fully removing the nut (sorry being lazy), but, I am getting a digital reading of somewhere between to 10.5 and 11mm so going by the M12 rule the lower setting should be correct???

Please excuse my nativity in all this....am learning as I go along......

[Dave Milnes]

It is confusing when the official manual contradicts itself.
What I mean is ( I don't know the 125 that well ) is there another nut or bolt attached to the flywheel that is small(ish) that the 54-60 figure could be for, then the higher 116 figure can only be for the centre nut onto the shaft?
The official manual states
clutch bell nut - 78
clutch locking collar 78
driving pulley nut - 93
flywheel nut 116
Then on the next page of maximum tightening torques according to material it says
M12 in iron or steel 100
M14 in iron or steel 145
So this would lead you to believe that if the thread was 13mm dia then 116 would be a safe torque to attempt.
I'd probably start lower and see how this feels, building up and stopping at the first sign that it feels really solid.

[Mackay]

Many thanks for reply and info...sorry I am a bit slow on the understanding front, but think I get it know

Have been out and properly measured the shaft and it is definitely an M12 and there do not appear to be any smaller or bigger bolts linked to the fly wheel. So based on the info from the manual about M12 in iron or steel maximum of 100 it must then be the 56-60 figure I guess??

Anyone know a definitive answer on this one??

[The Bern]

I'm guessing the second chart will be a maximum value to be used if the manufactuer has not given a specific value for a particular application.

 

[The Bern]

Got it

The answer is different engine types, the workshop manual covers both & has a generic chart as well,

X9 250 cc 4T .... has engine prefix MFO4E

X9 250 cc 4T 4V has engine prefix M223M

(taken from page 10)

Torque 116Nm on page #19 (is for X9 250 cc 4T with engine prefix MFO4E) remember to apply the bracketed foot note on that page ...
Lubricate parts before assembly

Scrolling down the manual to page 31
We find the informationn that applies to X9 250 cc 4T 4V (with engine prefix M223M)
54 to 60 Nm  this time with a different but equally important foot note ...
Apply threadlock, Loctite 242