New sram s1000 crank bolt keeps coming loose!!
Bought my flash 2 alloy couple of weeks ago and notice the drive side crank bolt was very loose. About 2 rides later it was wobbeling around again. Checked again and it took another almost full turn.
Now i dont have a torque wrench so it could be that im being to nice to it. But is this a common problem? This is a new crank style to me as it has some type of adjustment on the non drive side(mabye for spacing) that has an allen bolt lock on it.
Anything else i should be checking?
SRAM torque spec for that bolt it fairly high. I'll see if I can find the specific for that crank
Its sbout 40ftbs. I cranked it good last time. I "heard" it if you know what i mean. Untill i get a torque wrench I will just keep checking it every couple days. Just wasnt sure if I was missing anything.
*you beat me to it.
I've never had mine come loose on my few sets of stylo cranks. Maybe put a dab of blue lock tight on the threads?
There's a drive side crank bolt? on my S1000 crankset the drive side crank is attached to the spider. The only thing that holds it in is the bolt on the non-drive side.
If the bolt wasn't torqued properly during the initial build, and the LBS did not check it (which should be done) a bolt that continues to come loose, will always come loose. This is due to the spindle/crank interface becoming wallowed out, not allowing a snug fit.
If I were you, I'd make a trip to the LBS where you purchased the bike from and have them check it and torque it to specs. If it continues to come loose, make sure that the LBS takes care of you. Don't be a duoche canoe about it, but stand your ground.
I will verify with a torque wrench and go from there. If it comes loose i will let them know. I bought it in florida and live along way away.
Are the bolt and both mating surfaces lubed?
If the mating surfaces are not lubed, the parts may be binding before fully mated, allowing the bolt to come loose after some applied torque and vibration. If dry, the bolt itself may be experiencing more friction than expected and therefore requiring more torque than specified to get the bolt to mate the parts properly.
If everything's lubed, I'm not sure what's going on here, but just to hedge against the odd situation, I would check to make sure the bolt is not somehow bottoming out (such as if the wrong length bolt had been supplied, the bolt hole not properly formed, or something lodged in the hole causing the bolt to essentially bottom out.
I can barely get my mouth around it.
Originally Posted by frdfandc
Once ridden and it has loosened, you actually damage the crank arm, and it will never set right again. It will continue to work itself loose, even with locktight and that bolt is as tight as possible.
Chances are you will need to replace you cranks. I've seen rookie mechanics get fired on the spot for not checking crank bolts. I would have your shop go over the bike completely. Make sure they greased the pedals. And you know what rookie wrenches do? They build up new bikes out of the box.
That explains a lot actually.
Originally Posted by machine4321
Depending on region.
Well had a long 26km ride today with super rocky trails. It held up fine, when I took the crank off all the mating surfaces are libed and show no wear. I must have caught it early.
Here is my theory. The non drive side has a lock nut type set up that sets the depth for the drive side spindle. The gap between the back of the non drive side crank arm is about 10mm from the chain stay(clearance). The drive side clearance is mabye half that. My guess is the lock nut needs to be adjusted to allow the drive side spindle to stick out further so it can make full contact.
I assume the installation goes like this: loosen locknut/adjusting ring all the way. Allow spindle to come as far out as it can and tighten drive side crank bolt to spec.
Then tighten adjusting ring untill proper spacing is achived. Tighten lock nut on it and should be good to go.
Cliff note is the spindle is offset right now causeing the non drive side crank arm to be further outboard then it should be, causing the the drive side to not mate to the spindle at full depth.
What you guys think.
Im sure that was it. The preload ring was loose and must have worked its way inboard. Just pedaling would have caused it to work inboard.
When I was tightening the drive side bolt it was creaking, this is why I didnt over due it. Once the preload ring was all the way back out the crank bolt felt nice going in and i could tell it seated all the way. I thightened the preload ring by hand untill the was no play and sinched the lock bolt on the preload ring.
Also had to adjust the front derailer because it wasnt straight.
Morel is check you new bike over if you havent built it yourself
What drive side nut? Post a picture of the s1000 cranks because they sound not like these
Sorry its a bb30 not gpx. Shoul have mentioned that. Where your hollow part is, mine has a 10mm hex that threads into the spindle