Triumphrat

Snakeoil

I would doubt that you would be able to get a socket on the nut due to lack of overhead clearance.

You can torque nuts with a common box wrench (ring spanner). Just use a spring scale or digital strain gauge to pull on the other end. Torque is mass x distance so just just measure the wrench where you willl place the spring scale and do the calc.

If you are using a combination wrench and the open end where you will hook the scale is 8 inches from the center of ring end, then you just mutiply 8 inches x the lbs you read on the scale for the torque reading. So if you want to torque nuts to 200 inch-lbs, 200/8 = 25 lbs. So 25 lbs is what you want to read on the spring scale.

If you want to measure in foot lbs, 200 inch lbs is 16.67 ft-lbs.

So take your 8 inches, divide it by 12 to get the fraction of a foot, which is .667 foot. Now divide 16.67 fl-lbs by .667 ft and you get 24.98 which rounds to 25 lbs, which is the force you read on the scale for foot lbs. Notice it is the same mass, 25 lbs in both cases because 200 in-lbs = 16.67 ft-lbs.

The other key point is always pull the scale 90 degrees or perpendicular to the axis of the wrench.

Got it?

regards,
Rob

loxx101

You know, I've never even thought about it that way... Damn good point!

I've always just used a torque wrench!

Snakeoil

Measuring torque on used hardware is an approximation at best IMHO. Variables such as dirt, damaged threads, oil or other lubricants all vary the friction which varies the amount the bolt is stretched for a given torque read. Add to that the accuracy of the torque wrench, not to mention how well it is calibrated all add to the variability. My experience with spring scales is they are pretty accurate. They are at least accurate to within 1 lb and that's all you need. So using a spring scale might even be more accurate than using a torque wrench.

There is a used tool shop near me and he has a torque wrench calibrator bolted to his wall. Never did ask him were it came from, but it is a pendulum that swings thru 90 degrees with a weight on the end. The scale is an arc graduated in in-lbs and foot-lbs I believe. It's been a while since I've used it. I've brought a couple Taiwan click type torque wrenches in there and calibrated them. Then I ran them thru their range and they were remarkably accurate.

regards,
Rob

mtnbkr01201

Total bummer, I wish I had read this post before, I'm going downstairs right now to do the upper end on my TR7RV, as well as new ring's, base gasket - the works.
Would love to replace the base nuts with stainless (another time).

Bill

An Irishman on a Limey

mtnbkr01201

Be very careful as to the light settings on a click type torque wrenches, got a brand Click Type (always used old school) new one from where I work, used it a few times on wheel axle nut, head bolts, no problem, when I did the front wheel bearings - and torqued the nuts for the caps - stripped one clean - not the nut - but the entire stud, now using a locktite to hold.

Crap

obollox

Two or three open ended spanners held on to the hex nut can help
prevent rounding it off.

DAVE M

It's ages since I did the base nuts but don't think they were torqued.

I am pretty sure that H Hancox just did them "tight" if you use the correct spanner, then you're limited as to how hard you can tighten them anyway.

I have 6 sided stainless on mine ( I think!) the bike is in the garage and it's cold.

loxx101

Surely if you were torquing them to the correct setting, no matter what type of torque wrench it is, if it strips then the stud needed replacing anyway?

Yeah, where I did my apprenticeship we had a test bench for torque wrenches that were calibrated every 6 or 12 months. I have a Norbar torque wrench that maxes out at 50Nm or something (ideal for Triumph engine, that's why I bought it). I'm going to have somebody I know who still works where I used to to check my torque wrench for accuracy before building.

As far as I can remember (without looking) the Triumph book states torque figures dry. Using lubricant on the threads could cause you to over tighten them considerably.

rubber biscuit

Tighten it up' 'till it snaps or strips, back it off a half turn....perfect!

loxx101

Haha! If only there were a like button. Facebook is spoilt.