I recently took my two-year-old Trek 2700 in for a tune up, and was convinced that I needed a new crank. I left the bike at the shop, and a week or so later got a call informing me that the crank was stripped, meaning they couldn't get a crank puller in it and it was going to take a little extra time to fix. I asked what could cause that, and was told "Somebody trying to take the crank off. Don't worry, it isn't going to cost you any extra." I took this to mean that the mechanic had stripped the crank while trying to take it off, and was going to take care of it.
A couple of days ago, I go another call from the shop. They apparently haven't found any way to get the crank off, and don't know whether they'll be able to. Furthermore, they're now denying that they did the damage to start with. My question is this: is there any way the crank could have gotten stripped through normal wear and tear? This bike has never been in the shop before, and I have done any work on it except oiling the chain and changing a tire one time. It's never been wrecked, and certainly nobody has ever tried to take the crank off. Before I get into a big fight with the shop, I want to be sure I'm in the right on this. Anybody?
is there any way the crank
is there any way the crank could have gotten stripped through normal wear and tear?
Yes.
*edit* okay, re-reading let me make sure I understand. Do you mean it's stripped where the crank slips onto the bottom bracket? Or it's stripped where the puller would tap into the crank?
Crank puller
They say they can't get a crank puller into it to get it off, so I assume it's stripped where the puller would tap into the crank.
Yeah. Good point. It's real
Yeah. Good point. It's real easy to strip the part of a crank that goes on a square taper bb if you let your cranks get a little loose and then ride a bunch on em.
But that wouldn't
But that wouldn't prevent them from taking the crank off, right?
right-o
right-o
i had a crank that virtually
i had a crank that virtually become one with the BB (mountain bike jump gone wrong). my crank puller could not pull it off. It was a major ordeal to remove it, but like you said, there's always a way..... I had to do things a self-respecting bike shop would not likely attempt.
If the BB square bracket is damaged, it will damage any new cranks you put on it (lesson learned the hard way). Might need both a BB and cranks.
2-year-old Trek 2700
I doubt it's a square taper bb. Probably the tech didn't pull out the little washer that's under the crank bolt before threading in the (outer part of the)crank puller. Then when they screwed in the inner part, it pushed up against that washer instead of the bb spindle, and insta-stripping ensued.
I can't think of any normal wear-and-tear that would strip the inner threads of the crank, because they should be covered by the crank bolts. but who knows?
It's real hard to strip a
Depends on type of cranks, bb, etc.
It's hard to strip the crank-pulling threads on a crank without trying to use a crank puller to take it off. It's relatively easy to strip a crank with a crank-puller if you're not careful.
There is _always_ a way to get the thing off. If it's really that shot, you can use a dremel to cut out a section of it.
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burp
burp
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blah blah brace frame hit with hammer up at with crank bolt loose gotcha
Gear puller. Rent one from
Gear puller. Rent one from Autozone.
Sounds like they stripped
Sounds like they stripped it, but it would hard to prove or get them to fess up.
You may be able to use a pickle fork to pop it off- auto tool used on ball joints.
threading can be an issue on
threading can be an issue on lower-end cranks. sometimes they aren't tapped correctly from the manufacturer, sometimes the assembler (factory, not shop) will airtool the hell out of something and damage the first couple of threads, sometimes the kid with the wrench is a numbnut, and sometimes the wrench (puller) has been used in the commission of a stripping, and threads (from the aluminum crank) will reside between the threads (of the steel tool) like corn stuck in your teeth. When you use a corn-filled puller on an otherwise good crank, well you can fill in the rest.
so the short of it is, it could be the manufacturer, the factory worker, the shop worker or the tool...
...or gnomes.
Hard steel tool on soft
Hard steel tool on soft aluminum cranks. I had a a set of LX cranks do that along time ago. I just used a gear puller to get it off... then used that as an excuse upgrade my cranks!