My non drive side crank arm came loose and fell off the bottom bracket. I almost crashed hard.
Before I go back to the shop that installed my crankset a few months back and give them a few choice words, is there any other reason why this could happen other than it not being properly installed?
You never felt it coming loose on any previous rides?
You never felt it coming loose on any previous rides?
No, I never felt it coming loose on previous rides.
I felt it for a second or 2 right before it happened but that is it.
I have never heard or seen this happening but have to believe you had some warning. How can a crank be so loose as to fall off and you as a rider not notice? It’s always our (the riders) responsibility to make sure equiptment is operating before going out for a ride. You should always go through a prelim 20 seconds to make sure basic things are good to go. I have never had a loose crank as I said but have to believe you feel something is awry before it falls off. No?
You never felt it coming loose on any previous rides?
No, I never felt it coming loose on previous rides.
I felt it for a second or 2 right before it happened but that is it.
And, I’m guessing that you don’t have any of the bolts from the arm? What kind of crank is it?
I have never heard or seen this happening but have to believe you had some warning. How can a crank be so loose as to fall off and you as a rider not notice? It’s always our (the riders) responsibility to make sure equiptment is operating before going out for a ride. You should always go through a prelim 20 seconds to make sure basic things are good to go. I have never had a loose crank as I said but have to believe you feel something is awry before it falls off. No?
I have never heard of this happening either. I agree that it is my responsibility to go over my bike and check for loose bolts before I ride which I do pretty much every ride. I have never checked my crank though in the past. It is just something I have never had come loose in 10 years of riding. I will make sure to check it in the future.
And honestly, I never felt anything before the ride. I literally felt something wierd happening (I thought it was my pedal at first) and looked down and it came it right off. This was about 1 hour into my ride.
You never felt it coming loose on any previous rides?
No, I never felt it coming loose on previous rides.
I felt it for a second or 2 right before it happened but that is it.
And, I’m guessing that you don’t have any of the bolts from the arm? What kind of crank is it?
Its a DA 7900 SRM. The bolt is still in the crank arm. I should post of picture of this.
The same thing actually happened to a buddy of mine while we were riding together. He did go down, but luckily it was on a long climb so he wasn’t moving super fast. Can’t recall what kind of cranks he was on.
Its a DA 7900 SRM. The bolt is still in the crank arm. I should post of picture of this.
There should be 2, no? Is it broken or stripped any? The only thing I’m thinking is that if this did happen suddenly, then somehow the cap screw material was bad or possibly overtightened and then broke. But, if it broke, then I’d also think that it would shoot out and there’d be nothing left for you to post a picture of. Yet, you have the screw. Weird.
happened to my buddy on his trainer.
he installed it and never took the time to wonder why it was a bit difficult to get on.
Check to see if it was crossthreaded.
Its a DA 7900 SRM. The bolt is still in the crank arm. I should post of picture of this.
There should be 2, no? Is it broken or stripped any? The only thing I’m thinking is that if this did happen suddenly, then somehow the cap screw material was bad or possibly overtightened and then broke. But, if it broke, then I’d also think that it would shoot out and there’d be nothing left for you to post a picture of. Yet, you have the screw. Weird.
So you are saying I should have no bolts in the arm?
http://i37.photobucket.com/albums/e95/rcntly4298/IMG00005-20100608-2234.jpg
I’m not saying one way or another. I was thinking out loud – so to speak.
Ok, so you have the fixing bolt, the one facing up, and it appears that you have one of the clamping bolts, which is the bolt I was referring to. Is the other one there?
Take the clamping bolt(s) out and see if they’re stripped from cross threading. See if they’re broken or abnormal in some way. Look at the splines on the crank and the slots in the arm – any broken spots?
I’m not coming up with any good answers for you. Are you familiar with your shop? I mean, do you go there often?
Oh, is the stopper plate positioned properly?