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Discussion Starter · #1 ·
I have a question about the torque load for the "star" shaped bolt that "sandwiches" the left and right side crank.

View attachment 274928

How do you determine the right amount of torque? The bolt is of a weird shape that you need a special tool to remove or install.

Right now I have the wavy washer pretty much flattened in my bike and my crank feels very stiff and doesnt free spin at all. If I loosen it, it feels a little bit smoother but Im not sure if that would not be enough to keep the crank from sliding.
 

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You should go to Shimano's TechWeb site and look at the Service Inspection doc (SI) for your particular crankset but they are all pretty much the same even for the road bike cranks.

Use the TL-FC16/18 to tighten the cap.
Tightening torque: 0.7 - 1.5 N·m {6 - 13 in. lbs.}

Basically the plastic cap applies a light pre-load to the bearings, it doesn't hold anything together, that is a the job of the two socket head screws which you tighten last to 12-14nm (106-122inch pounds).

I assume the wavy washer you refer to is between the crank and the BB bearings, thats non standard, Shimano use 3 different thickness washers depending on the width of your BB. Again refer to the SI for positioning of the washers on both sides of your BB.
 

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Don't use any tool. The idea of the plastic tool is that you use your fingertips to turn it, and when it is finger-tight, that's enough.

Your crank feels stiff and does not turn freely because you have overtightened the bolt. It is only for preloading the bearings. It does not hold the crank in place.

Repeat, do not use any tool, no torque wrench, nothing. Fingers only.
 

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Many mechanics will tell you to make that piece finger tight and then even back off 1/4 turn before you tighten the pinch bolts. The pinch bolts are the only thing that hold the crank arm on and you are best off not to turn this cap too tight. If you really wanted to use a torque wrench, you can pick up one of these:

Park Tool Co. » BBT-10 : Adjusting Cap Tool : Crank Tools

and then you can use one. I used this on a new build with a torque wrench on a Chris King BB and it has been absolutely flawless. But honestly you can do the same thing with the "finger tight" method.
 

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Discussion Starter · #7 ·
Thanks for the reply. I just rebuilt the crank with the hand tighten method and it seems its still pretty stiff. I even backed off the nut a quarter to half a turn and it did loosen up, but not free spinning smooth. I dont have the chain hooked up and I cant get the crank to do a full rotation before stopping. If I apply no preload on the bearing itself then it will spin freely

Im suspecting the adapters are creating too much drag somewhere.
 

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Discussion Starter · #9 ·
I bought the bike in September so 5 months now. I had the bearing changed out last month since I had a noise issue which I took the bike back to the shop and they found out the bearings in my bottom bracket to be shot. But turns out it was unrelated.

One thing I forgot to mention is my bike uses a PF30 and the shop who built my bike used Enduro's BB30 to HT2 adapter. Im having a hard time finding any documentation or instructions on how to properly install their adapters and I am suspecting the adapters, when the preload nut was tightened, is pressed against the face of the bearing binding the rotation and making it stiff.

When I take the preload out of the crank my crank spins freely.
 

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I bought the bike in September so 5 months now. I had the bearing changed out last month since I had a noise issue which I took the bike back to the shop and they found out the bearings in my bottom bracket to be shot. But turns out it was unrelated.

One thing I forgot to mention is my bike uses a PF30 and the shop who built my bike used Enduro's BB30 to HT2 adapter. Im having a hard time finding any documentation or instructions on how to properly install their adapters and I am suspecting the adapters, when the preload nut was tightened, is pressed against the face of the bearing binding the rotation and making it stiff.

When I take the preload out of the crank my crank spins freely.
It seems to be a popular misconception that BB bearings are pre-loaded. They aren't. All those adjustments are meant to do are close the gap/ take up play in the crankset/ BB interface/ assembly. Once that's accomplished, stop tightening.
 

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So what your saying is, tighten the nut till there is no more side to side movement and stop?

Should I take out that wave washer?
Why are you using a wave washer? I've never seen that specified in any Shimano docs for crankset installs.

Yes, tighten the nut till there's no play and no binding. If there's binding, back it off a bit. BTW, don't confuse binding with a little drag. Shimano cranksets generally exhibit some drag, especially with new BB's.
 

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It was put in there by my shop. As mentioned before, this is a pressfit30 bottom bracket with adapters for shimano cranks.
Yes, I scanned through your thread and saw that your bike had a PF30 BB and you were using the Enduro adapters.

I've seen nothing indicating the need for wave washer for that install, so I'd suggest removing it, then reinstalling tightening the plastic nut (hand tight) till there was no play/ no binding.

Some cranksets do require a wave washer, but not Shimano.
 

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Discussion Starter · #16 ·
Yeah, I have seen that and other similar products where they completely replace the PF30 bearing with a conversion.

I might look into that depending on how much it would cost to have it shipped to me. (I live in Hong Kong...shipping will be ridiculous)
 

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Yeah, I have seen that and other similar products where they completely replace the PF30 bearing with a conversion.

I might look into that depending on how much it would cost to have it shipped to me. (I live in Hong Kong...shipping will be ridiculous)
I just offered that link as a FYI. Once installed and adjusted correctly, your BB setup should prove durable.
 

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Yeah, it cost 85 for the conversion and another 80 bucks just to ship it.

Its ridiculous how expensive the shipping is.
I ran into that when I was selling a frame to a potential buyer in Taiwan. Turned out shipping was ~$150 so he backed out of the deal.

Let us know how you fare with your BB setup. I know the crankset will be fine, but am curious how the Enduro adapters will hold up. They look to be of high quality.
 
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