LBS "tightened" my crank, but it's loose again and clanking
08-16-09, 07:46 AM
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LBS "tightened" my crank, but it's loose again and clanking
I gad some play in my crank and so I brought it in to my LBS. I also had chain hop and a new chain didn't fix it so I had them swap in a new rear cog. I had asked them to 'service" my crank and mentioned grease. When I picked it up they said all it needed was to be tightened. I rode it 5 miles and it is making God-aweful clanking sounds and is loose again. (btw - it was fine when I test rod eit outside the shop)
what the heck is clanking?
do I take it back to this shop or go to another?
what the heck is clanking?
do I take it back to this shop or go to another?
08-16-09, 08:10 AM
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If it's a "square taper" crank and you rode it while it was loose, you may have damaged the crank to the point where it will never stay tight again.
Aluminum square taper cranks have to be a very tight fit on the hard steel bottom bracket spindle and the recommended installation torque is very high. If the cranks get loose for what ever reason, usually because they weren't installed properly to begin with, the steel spindle will distort and damage the hole in the crank so that it will never fit properly again.
If that's the case, your only option is a new crank.
Aluminum square taper cranks have to be a very tight fit on the hard steel bottom bracket spindle and the recommended installation torque is very high. If the cranks get loose for what ever reason, usually because they weren't installed properly to begin with, the steel spindle will distort and damage the hole in the crank so that it will never fit properly again.
If that's the case, your only option is a new crank.
08-16-09, 08:19 AM
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[QUOTE=HillRider;9495868]
If it's a "square taper" crank and you rode it while it was loose, you may have damaged the crank to the point where it will never stay tight again.
/QUOTE]
Hi
That sounds like my problem with my daughters bike, pedal comes loose and the centre nut holding it in place loosens too. Tightened it a few times, but the same thing happens.
On inspecting the bolt, the first quarter of the thread is stripped. Maybe a new bolt will solve the problem.
G
If it's a "square taper" crank and you rode it while it was loose, you may have damaged the crank to the point where it will never stay tight again.
/QUOTE]
Hi
That sounds like my problem with my daughters bike, pedal comes loose and the centre nut holding it in place loosens too. Tightened it a few times, but the same thing happens.
On inspecting the bolt, the first quarter of the thread is stripped. Maybe a new bolt will solve the problem.
G
08-16-09, 03:55 PM
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If it's a cheap, old bike and you don't want to spend money on it.....take crank off and try tapping
(alright, hammering - gently) the inner face of the crank around the axle hole. This may take some time/trial and error, but it can work if you're desperate. I've done it in the past a couple of times but not with a decent/expensive bike !
(alright, hammering - gently) the inner face of the crank around the axle hole. This may take some time/trial and error, but it can work if you're desperate. I've done it in the past a couple of times but not with a decent/expensive bike !
08-16-09, 03:56 PM
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It's a dilemma. On the one hand, the shop which carried out the work should be compelled to do it properly. On the other, you may be reluctant to entrust it to them again. I incline toward the latter course, but I do my own work anyway, and it's hard to imagine yourself being dependent on other people (which I guess I would be if this computer went AWOL). Your call. If you decide they should put it right, ask to speak to the shop owner or manager. Say as little as possible, after explaining what you requested to be done and the present outcome. Sometimes, we put ourselves at a disadvantage in these situations by talking too much to cover our discomfiture, and predatory merchants sense this. If you know any outlaw bikers, it wouldn't hurt to take them along as well, just for a bit of background menace. Tattoos are good.
What's clanking is probably one of the cranks, which is loose on its taper. If it were mine, I'd feel happier if the entire bottom bracket were taken apart and regreased, so the balls and races can be checked - unless it's a sealed one, naturally.
What's clanking is probably one of the cranks, which is loose on its taper. If it were mine, I'd feel happier if the entire bottom bracket were taken apart and regreased, so the balls and races can be checked - unless it's a sealed one, naturally.
Give me a ****ing break.
08-17-09, 02:11 AM
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If you've got damaged crankarms from riding it previously when it was loose, most likely there's absolutely nothing the shoppe can do to fix it for you. You'll need to buy a new crankarm.
