Singlespeed & Fixed Gear - bent flange = dead rim?

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View Full Version : bent flange = dead rim?


sers
03-06-06, 10:52 PM
earlier today one of my neighbors asked me to help him fix a flat. it appeared that the tire had slipped off the flange at one point - a large tear in his tube seemed to confirm this. when i checked out the rim, the flange was dented about 1mm in at a small point.

i ended up telling him that i couldn't fix his flat because his rim was dented. what i couldn't tell him is if this could be fixed. i didn't want to attempt it myself. is it possible to straighten the flange of a rim, or is his wheel toast?


teadoggg
03-06-06, 10:54 PM
It depends. Sometimes they can be gently bent back into position. your LBS will be able to advise. It's hard to tell without seeing it.

endform
03-06-06, 10:55 PM
You can ride that thing till the cow's come home. I'm working on putting a 3rd dent into my current rim. I'm looking forward to probably next month at this point. It's cool to ride, but it's really really really f*****g annoying when using a rear rim brake though. I've just let mine be but anecdotal evidence from previous forum member's posts suggest that it can be bent back.


Alexi
03-06-06, 10:56 PM
most lbs will say not to fix due to liability issues, you can fix with 2 ajustable wrenches, by moving them slowly over the bent area, one after the other. so you clamp one where the rim is still straight and the next one right next to it, then bend straight, move the first one to the other side of the first bend a little and repeat.

edit. why can't I spell.

beppe
03-06-06, 11:00 PM
Yes, you can usually bend it back. No offense to teadogg, but IME most shops won't bend it back for you, and many won't even tell you how, for liability reasons.

Maybe West Town Bikes (http://http://www.westtownbikes.org/) can help?

sers
03-06-06, 11:20 PM
You can ride that thing till the cow's come home. I'm working on putting a 3rd dent into my current rim. I'm looking forward to probably next month at this point. It's cool to ride, but it's really really really f*****g annoying when using a rear rim brake though. I've just let mine be but anecdotal evidence from previous forum member's posts suggest that it can be bent back.

cool. the tire he had on there was a folding bead he'd been riding for a while. would a wire bead help keep him running longer, given that foldings can stretch after a while?

endform
03-06-06, 11:34 PM
I've got foldings on mine and have never had any problem. It's a pretty tight rim to begin with though. I don't think he'd have to worry about it coming off of the rim, especially since it's only bent 1 mm in. I have a 4 or 5 mm dent in mine and my tires never flown off while bombing down a mountain or anything.

plantdude
03-07-06, 09:09 AM
Just take your time and you should be able to bend it back. Go slowly and use a tool such as open endend wrench or adjustable wrench, although there is a tool made specifically for this:

colinm
03-07-06, 09:46 AM
I've brought one back that had nearly closed itself. Granted it's probably not as strong as it used to be, but it trued and there's no real wiggle in the rim wall. I trust it, but I wouldn't say it's as strong as a new rim.

Ira in Chi
03-07-06, 10:02 AM
Just take your time and you should be able to bend it back. Go slowly and use a tool such as open endend wrench or adjustable wrench, although there is a tool made specifically for this:

This tool is designed for steel rims.

Ira in Chi
03-07-06, 10:13 AM
Do you guys ever think for a second that there is a reason why shops won't do this? Not to be a jerk, but it DOES WEAKEN THE RIM when you bend a severly dinged alloy flange back into place. Aluminum loses it's strength when stressed, it's a fact- the crystaline structure changes. They are not telling you this just to annoy you. Not that you can't ever get it to work, but think twice before doing this and then running high-pressure tires, and if the sidewall cracks sometime down the road, understand that it is your own fault.

r-dub
03-07-06, 11:24 AM
Do you guys ever think for a second that there is a reason why shops won't do this? Not to be a jerk, but it DOES WEAKEN THE RIM when you bend a severly dinged alloy flange back into place. Aluminum loses it's strength when stressed, it's a fact- the crystaline structure changes. They are not telling you this just to annoy you. Not that you can't ever get it to work, but think twice before doing this and then running high-pressure tires, and if the sidewall cracks sometime down the road, understand that it is your own fault.

^ what he said. I've got one of these tools, but I would never use in on an aluminum rim. If it's just slightly bent, leave it bent. It will be more safe than a rim that's been bent twice. If it's too far gone for that, make art out of it, it's riding life is over.

RedDeMartini
03-07-06, 11:26 AM
Are people so scared to say NO?
No, it is not a good idea, but it can be ridden. It is so easy to do a rim swap, why not just save yourself the hassle? A LBS is not a scam, thye know it won't work and they don't want to be held responsible when you keep *****ing about it. Ride it as long as you need to but it is broken. Swap a rim onto there ASAP, you can usually get them for free if somene ****s up a hub. Then the whole wheel goes in the trash, your own private shopping trip.

Rim swap: tape the new rim to the old one. Pass the spokes across and get them finger tight,don't use a tool. The take them to the localshop to get it tensioned.

Easy