Bicycle Mechanics - How tight? or how do I estimate 360 in/lbs

I just put a sram 8sp cassete on my new deore hub wheels. The instructions from Park tool state tighten to 360 inch pounds. I translated to 30 ft/lbs (correct) and guestimated.


Can I tighten too much? Too little?

Any ideas on guestimatting?

Or should I just break down and get a torque wrench?

thanks

I never tighten those lockrings anywhere near what they specify. It makes cassette removal much easier. I have a torque wrench but rarely use it.

I never tighten those lockrings anywhere near what they specify. It makes cassette removal much easier. I have a torque wrench but rarely use it.

30 ft/lbs:eek: :eek: for a lock ring? You'll never get it off if it doesn't break first! I use that kind of torque for a crank but never the lockring. The lockring doesn't do anything other than hold the cassette in place. Looking at the Sram website they do call for 40N-m but geeeze! I put it on so that it clicks once or twice. Any more and it'll be tough to get off...trust me;) I broke a spoke on my last tour and turned the hypercracker the wrong way (freewheel vs cassette...I'm an old guy:o ) and tighten the ring probably 6 or 7 clicks and I thought it had been welded in place

I put it on so that it clicks once or twice. Any more and it'll be tough to get off...trust me;)

I agree. I usually tighten by giving it only a couple or three clicks, and no more...:)

Firm, but not hard.

OK, so I got a lot of clicks as i was tightening it.....it is on tight :eek: Best bet to try to loosen it a bit now or just wait and cuss a lot later??????

OK, so I got a lot of clicks as i was tightening it.....it is on tight :eek: Best bet to try to loosen it a bit now or just wait and cuss a lot later??????

Sleeping dog. Let it lie. Hope you don't have to take it a part on the road.

OK, I'll bite. What causes the "clicks" I put a new Shimano cassette on a new wheel, and I DID get a few "clicks" before I quit! Thought I might have broken or twisted something. Sooooo, what are the clicks??

OK, I'll bite. What causes the "clicks" I put a new Shimano cassette on a new wheel, and I DID get a few "clicks" before I quit! Thought I might have broken or twisted something. Sooooo, what are the clicks??They're really not 'clicks' but you feel the lockring 'indexing' more or less as you tighten it due to the serrations on the lockring.

AHHHH, I thought and was hoping that was the answer! Would have been very bad to screw up a new cassette AND wheel! Well, now I know. :)

Thanks Fixer

OK, I'll bite. What causes the "clicks" I put a new Shimano cassette on a new wheel, and I DID get a few "clicks" before I quit! Thought I might have broken or twisted something. Sooooo, what are the clicks??The clicks are caused by the serrations on the back side of the lockring against the serrations on the outermost cog.

Yah, no need to tighten up the lockring too much. Unlike the crankarm, there's not much lateral or torque loads on that lockring.

As an old wrench... I'm just amazed the reaction this site’s members have to the topic of torque.

If you want to put 360 inch/pounds on something here is how you do it. You can convert inch/pounds to ft/pounds by dividing Inch/pounds by 12 (12 inches in a foot) 360 inches = 30 feet so you get 30 ft/pounds. Now to get that to the bike without a torque wrench is easy. Take a wrench that has a handle that is at least one foot long. Connect it to the nut…whatever… and then go one foot (12 inches) away from the center of the socket/nut you are connected to. What you have just done is find the “foot” part of “foot pounds” now you need to apply 30 lbs of force to the wrench at the one foot handle mark.. If you have a bathroom scales you can try pushing on it and get the feel of 30 pounds of weight/force. Apply that same feeling of force to the wrench at one foot out and you are going to be close to the specs. If you put 360 pound of force on the wrench at one inch away from the center of the nut you would be at the same force. I don’t even weigh 360…(and never want to) so I use the wrench one foot out.

The only problem I have removing stuff from a bike is the dinks that think they know more than a torque wrench. (Or it is rusted on) If you work on stuff enough you do learn the feel and can do it without a torque wrench. The average Joe that puts on part once every few months or so…will not get it close. With the proliferation of carbon parts torque is so important. I have checked bikes that have so much torque on handle bar clamps that I make people sign a release so I’m not liable when the bars fail.

A carbon handle bar manufacturer conducted research at the TdF two or three years back. The old mechanics didn’t use torque wrenches. When the bikes were first set up the torques were at or very close to spec. Each day the Manufacturer would check back. The mechanics would check that nothing was getting loose by putting the non-torque wrench on it and checking. What was happen was each time they checked they added force to it. By the end of the Tour all of them had the handle bars so tight the Manufacturers had been exceeded and were at a failure point. If they would have loosened it then retightened it would have been fine. The manufacturer now requires use of Torque wrenches on their sponsored teams.

Good luck …as carbon comes more main stream torque becomes more important.

Cheers,
Dusk

In my experience, 3-4 clicks is enough. But you do need to tighten the cassette otherwise the lockring will loosen by itself. It happened to me once while riding on a coarse gravel road.

The OP is not talking about a freewheel cassette.

So, why would the mfr recommend so much torque? The custom wheels on my car have instructions that specify how much torque should be used to put the lug nuts on. I won't let any tire changer put the nuts on unless I observe the process - and I always specify 10 ft/lbs less than the mfr's recommendation. I once hit a pot hole in the dark - both right side wheels were ruined. I was only a couple miles from home and the tires were run-flat (although the impact ruined them also) so I was able to get the car home, but thought I would have to have it towed somewhere to get the two wheels off - so difficult were the nuts to remove. The mfr had supplied a special little doohigy that was supposed to fit into the custom lugs, then you used a socket wrench over the doohigy. Well, the doohigy was made of aluminum, and the force required to get those lugs to budge quickly overcame the strength of the aluminum which quickly was stripped of its shape by the steel lugs and became useless. I finally stopped by a truck repair shop, borrowed a very long handled ratchet with a - dogone, I forget what that type socket is called - one end fits over the wrench drive, the other has a hex wrench protrusion that fits into these “special” (not so special in my book anymore) lugs.

The added leverage and a steel hex allowed me to get those lugs off so that I could install replacement wheels/tires (it still took a lot of effort, and I was afraid I might strip those lugs and really have a nightmare).

I will never again allow those wheels to be torqued to mfr specifications. I bought that special socket to keep in the car.

It is very interesting to watch "mechanics" use a torque wrench, also. Many use their air driven "gun" to turn the lug on so tight that it already far exceeds the required torque, then, because they know I'm watching, will go around with the torque wrench, put it on and, of course, it clicks right away because the lug is already over tightened. More than once I've had to go onto the shop floor, insist that they back off all the lugs, tighten them by hand, then use the torque wrench to bring them up to the torque setting that I’ve specified.

Ah, woe is me!

Caruso

So how do you use a torque wrench for a cassette lock ring? My torque wrench has a 3/8" drive lug, and I've never seen a 3/8" socket large enough to fit the damn lockring tool. On a related note, why is it so bloody humongous? Why not make it 3/4" or 16mm, or something else more practical? Or just put a 3/8" drive hole in the end?

So how do you use a torque wrench for a cassette lock ring? My torque wrench has a 3/8" drive lug, and I've never seen a 3/8" socket large enough to fit the damn lockring tool. On a related note, why is it so bloody humongous? Why not make it 3/4" or 16mm, or something else more practical? Or just put a 3/8" drive hole in the end?A 24mm socket is what fits over my lockring tool. Easily found at any auto-parts store or Sears or Orchard Supply or Home Depot. The reason it's large is to attach to the outer housing of the freehub. You'll notice that the lockring spins with the cog. If it was smaller, it won't have anything to screw into. The large hole in the end of the freehub body is also needed to get the bearings, pawls and bearing-races in. Funny how the founders of the Imperial Standard are using all metric now....

A 24mm socket is what fits over my lockring tool. Easily found at any auto-parts store or Sears or Orchard Supply or Home Depot. The reason it's large is to attach to the outer housing of the freehub. You'll notice that the lockring spins with the cog. If it was smaller, it won't have anything to screw into. The large hole in the end of the freehub body is also needed to get the bearings, pawls and bearing-races in. Funny how the founders of the Imperial Standard are using all metric now....

I think the size of the lockring tool has more to do with it's former use as a freewheel removal tool. The freewheel tool that I bought for removing Shimano freewheels back when mastodons roomed the earth is the same as the cassette removal tools now days. Also the lockring tool has to fit around a 17mm nut on the axle of the wheel so it couldn't be much smaller.

So, why would the mfr recommend so much torque?

Lawyers?