overtightened clutch bolts caused by conversions, RESOLVED

:? while assembling my clutch I'm sure I made a big mistake. The manual says the torque is 7.2 lbs (foot pounds)

now two things happen
- my torque wrench has Nm and inch pounds
- the converters found online say 7.2 lbs is 32 Newtons and None of the online converters say Nm and non have inch pounds either

So is Nm different than Newtons?

Next, I proceeded to tighten the bolts to 32 Nm on the torque wrench and lots of bad stuff happened :cry:
- one felt like it snapped and when I removed it you can see it kinda split in the middle of the threads up by the neck
- the other 3 didn't snap but they all have clutch basket threads in the bolt threads, not much, about 3 threads worth, in this case that may be a lot
- one head snapped completely and is torqued all the way in the hole

:?: questions are, does anyone think the basket is salvagable and the newton question above

Leter Rip!

Thanks guys

 

Re: overtightened clutch bolts caused by conversions, need help

You just got a hard lesson in basic physics. A torque wrench measures TORQUE. You input a FORCE into the google conversion. Here's a link to what you should have put into google (it took me a while to get google to give me the right answer):

http://www.google.com/search?hl=en&safe ... =&gs_rfai=

Physically, you didn't account for the moment arm that you were applying the force (one foot vs one meter) so you were a little of 3x the torque you should have put on it. The bad news is that what ever you stripped will need to be replaced. You might want to look on ebay for a replacement clutch basket (for the inner hub where the threads are), and get new bolts and washers. I'm not sure if the springs will be damaged.

To convert from lb-ft to lb-in, just multiply by 12 - so 7.2 lb-ft is 86.4 lbs-in

Torque wrench does not measure FORCE, it measures TORQUE

 

Re: overtightened clutch bolts caused by conversions, need help

7.2 ft/lb= 86.4 in/lbs= 9.672nm= 976.2n-cm http://www.convert-me.com/en/convert/torque

Newtons per Meter (Newton-Meters) is different than Newtons per Centimeter;

32nm (Newton-Meters) is 23.6 foot-pounds which is why you damaged your parts.

If you pulled threads I wouldn't trust that clutch basket; just replace it.

I have found that clutch baskets (and whole assemblies) can be had on eBay for as little as $10; that clutch is common to all the 650's and 750's 81-83 inclusive so that will widen your search prospects. Just find somebody that's parting out a bike with low miles and go for it.

Or check with chacal and see what he has in the way of "raw material."

 

Got one on ebay, thanks guys