Crimped fork tubes? Fail torque wrench

[Leyton]

Hello All

Bit of a tricky one to gauge on a forum but... bike = CR125

I suspect my bitchin bar tourqe wrench is readying way off, I tourqed me fork clamps 15ft-pounds for the bottom and 16 on the top.. but to a spanner it feels way tooo night. They are hard to un do with a 10cm long 10mm spanner :P

Does this sound odd ?

They felt very loose when I first undone them, with the spanner.

If I have "Crimped" them as they say, is it a case of just loosening them off and it comes right or am I in for a world of poo ?

[pete376403]

did you lubricate the threads and under the head of the bolts? Threads and bolts in perfect condition? Many things affect bolt torque.

If you are trying to undo with a 100mm long spanner then its going to take 45 lbs force on the end of that spanner to equal the 15lbs on the end of a one foot (300mm) wrench

And if you've crimped the fork tubes I'd take that to mean thay have been crushed out of round, which to me is a Very Bad Thing

[Robert Taylor]

As Pete said, condition of threads and lubrication, also under the head of the bolts if they have a washer face. Correct torque is essential as is calibration of the torque wrench. Overtorquing is bad, especially with USD forks.

[Leyton]

Hello

Thanks for the replys

Yes I have lubed the threads and under the heads as per propper practice.. clean surfaces etc...


It is only when I checked it with a ring spanner with my hand that things did not "Feel" Right.

Upon measuring the out of round today, it appears my right fork is crimped by .1 of a mm at the worst! YIKES!!!

I reckon my wrench is faulty by around 12-15ft pounds. So imagine 25-30ft pounds on USD forks. I will confirm the calibration today after getting the new wrench... have not been unable to sleep Forks are expensive!

I am off to buy a $140 one today... And cross my fingers my fork bush's dont complain too much.


How much crimp is too much crimp ?, I did the ol fork compression test in the shed but I dont think I will know until I start coming off some jumps... and if my forks dont come back up.. then oh deer

Cheers
Leyton Smith

[pete376403]

If you take the springs out and move the sliders right up as far as they can go, do they come back out again without binding?

[Brian d marge]

I think you ate worrying to much
from the factory they are probably no round, do as suggested take springs out and see if the bind, I doubt they will
torque wrenches are only a guide........
Stephen

[Leyton]

Brian

Thanks for your assurance, I am picking you are totaly right...

I checked my old wrench aganist my newer more expensive one... and my old one was 8ft pounds out. I would like to think that is not enough to crimp the forks..

Next old change in those forks and I will inspect, or if they feel odd. But I think things are going to be ok...

Morrel of the story... if you are going to rely on tourqe settings for something that is sensitive to crushing.. remove the doubt, and don't use your old crappy supercheap $14 bar wrench that you purchased to fix that crap car from years ago

Thanks guys!!!!

Happy New Year!

[riffer]

I love my torque wrenches. I have two - a Warren & Brown Split Beam (which my father gave to me) which goes up to 120ft/lb, and a Facom S208-100 fixed ratchet click-type which, naturally, goes up to 100Nm.

Both fantastic wrenches. I thoroughly recommend them.

[gatch]

I forked out $300 for my norbar style 1/2".

I've used it twice..

[Crasherfromwayback]

I've used it twice..

Who'd ya hit with it?

[Madness]

I used to know a guy who worked in an ISO accredited test lab for tourque wrenches & tools. Warren & Brown was in his opinion the best brand of torque wench by far for accuracy and repeatability - by a country mile apparently. Norbar is a quality brand don't get me wrong but their designs have a shitload more parts than a W&B = not as good over time.

[gatch]

I used to know a guy who worked in an ISO accredited test lab for tourque wrenches & tools. Warren & Brown was in his opinion the best brand of torque wench by far for accuracy and repeatability - by a country mile apparently. Norbar is a quality brand don't get me wrong but their designs have a shitload more parts than a W&B = not as good over time.

Yup, if I'd had quick access to a beam type wrench that didn't cost my soul, I'd have had that instead. Less parts, more cost..