Clutch repair failure

Hi Nathanb, if you are using one of these throw it in the bin. NOW!

I actually have one of those also hahaha

Yes.

Even a high-quality Ft. / Lb. torque wrench operating at 3.0 Ft. / Lbs. is at the far, far lower end of it's operating range, well below the commonly cited ~20% & above operating range where accuracy is to be expected. Doubtful if final torque is really anywhere close to 3.0 Ft. / Lbs.

Rule of thumb we use is reasonable accuracy is expected within 25% to 90% of full scale. That differs somewhat from common field lore; it just gives a little extra margin of safety when working with decades-old fasteners & threads that may have been stretched by PO's and age.

An In. / Lb. torque wrench is a necessary addition to a well-equipped tool set when working with smaller fasteners and/or aluminum threads such as on old motorcycles of questionable history

Don't cheap out on torque wrenches. It only takes one broken fastener or stripped thread to consume many times the cost of a cheap torque wrench in needless repairs, not counting the cost of stress to the user.

Someone correctly mentioned oiled threads above. Unless otherwise specified, torque values assume all threads and fastener surfaces to be clean & dry. Easy to do in a factory environment, but when working in an already-oiled environment (like clutch baskets), not always possible. Recommendations range from a ~25% reduction to 40% reduction in torque when threads are lubricated. We generally use 30% less torque on oiled fasteners, as it's easy to do the math in our heads.

Much has been written about the how fastener lubrication affects torque requirements. Here's one example; there are many more:
www.engineeringtoolbox.com/torque-lubric...-effects-d_1693.html

We also 'sneak up' on final torque for most multiple fasteners - that is, we don't torque all fasteners to full spec on the first go. We do ~30 % full spec., then ~70 %, then final 100 %.

Torque conversion tables are ubiquitous on the interwebs, and are useful in calculating low values often found on bikes and reduction percentages for oiled fasteners and sequential tightening. Here is just one example:
www.kylesconverter.com/torque/foot--poun...o-inch--pounds-force


Good Ridin'
slmjim & Z1BEBE

Yes, 3ft/lb is a ridiculous number, anything that low would be quoted in in/lb.

I have 2 torque wrenches I have owned since the early 80's and only once during yearly calibration have had one sent back to head office for repair and calibration, they actually apologised and didn't charge me whilst giving me a loaner until I got it back, wow!

I don't think I will see that level of service or quality now that Snap on own them, Expensive crap from China.

Mc Tavish wrote: Hi Nathanb, if you are using one of these throw it in the bin. NOW!

Actually I have been schooled here on this forum that a beam style torque wrench is a very important tool to have. Its biggest advantage is used when installing torque to yield bolts. That style wrench lets you see when the torque value has stopped climbing and the bolt is slightly still rotating, That's when you know to stop as you have reached the yield value.

Hi Mikaw, This will be my last post regarding the merits of torque wrenches.
I stand by my comment about throwing that style of wrench in the bin, utterly useless!
They also have no place or use during the installation of TTY bolts.
TTY bolts are set to a prescribed torque value and finished with a degree wheel.

A beam-type torque wrench got my old Metro's engine back together and running for the 30k miles until I sold it...but I'm not trying to start a debate here :whistle:

OP, I'd really suggest getting a 1/4" drive in/lb torque wrench. Mine was $40 from Meijer, which is sort of a lot, but I use it more than I use my 1/2". In my opinion the investment pays for itself the first time you use it.

Hey one last question. you say if there's too much oil in it it could cause it to slip what if there's a little bit of a leak in the gasket which I was going to fix when I finalized it but could that cause it to slip also?

I hope you can see the settings for 3.5 ft. Lbs.

An oil leak wont cause slippage of the clutch.