I've a bent chain-ring and wonder about bending it back — sound idea?

I've a Fuji Newest 4.0, 2009; with a little over 300 miles on it. I've noticed a "shoop-shoop" sound while pedaling. If I fiddle with the position of the front derailleur the noise sometimes goes away. A closer inspection shows that the largest ring is bent; three gear tooth/tips look like they hit something and the ring bends out about 1/8" at that point.
I don't recall hitting a curb or hole. (I haven't used that gear yet and all the other teeth still look new.)
— My question is: will I do more damage if I just bend it back? Will I do damage to the "structural integrity" of the gear (metal fatigue by multiple flexing)?
— I'm 59, in decent shape, but I may never use that gear (hopefully I will), right now I'd like it to be quieter.

Thanks for reading. All suggestions/comments are appreciated.

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Permalink Reply by Gecko on June 24, 2009 at 5:18am
I've bent chainrings before and had to bend them back, it's not a big deal. Just get a crescent wrench and tighten it down on the bent part of the ring, then bend slightly whichever way it needs to go. Park also makes a tool specifically for bending chainrings but it's like 15 bucks. It's kind of trial and error, but to keep from having to bend it too much, just do a little at a time, it doesn't take much force to get it back to where it needs to be. Also, make sure the main part of the chainring is straight, don't just trust the teeth, some chainrings have purposely offset teeth to help with shifting. If the teeth are really bent you may need to have it checked at a shop to make sure you don't need to replace the ring. Bent/broken teeth will only get worse with time and could cause skipping eventually.
Permalink Reply by Ron on June 24, 2009 at 6:15am
El Gecko is right on. Also remember chainrings are relatively cheap and easy to replace.
Permalink Reply by Michael J Blane on June 24, 2009 at 6:47am
Thank you El Gecko and Ron! I'll give it a try in the next day or two.
If it were bent in toward the next smaller ring, I might think was to aid shifting. It's bent away, toward the pedals. And three of the teeth are slightly flattened on their points. Man, I really don't recall bottoming on anything.
If I end up wrecking it, then I guess I'll have to replace it.

Thank you both for your rapid responses.
Permalink Reply by Barry Niel Stuart on June 24, 2009 at 10:12am
Barry Niel Stuart wrote: As new as your bike is, I'd recommend taking it back to your Fuji dealer and letting him fix it under your warranty.
Permalink Reply by Gecko on June 24, 2009 at 10:28am
Good point Barry, I agree. I always forget about warranties because all my bikes are previously owned and/or custom.

Michael, it would be a good idea to take it to the shop who sold it to you and see if it's covered at least. When I worked at a shop, we had more than a few brand new bikes with damaged parts because of damage to the box during shipping. I dunno if we're opening a can of worms here but if the shop sold it to you knowing that it had damaged parts they could be liable for the repairs. Most likely they'll blame it on you and make you pay to replace the ring, but I'm not sure, it all depends on how honest the shop staff is.

Also, do you lock your bike outside for any amount of time?
Permalink Reply by joe on June 24, 2009 at 11:15am
i dont bend mine. i just break them in to several peices. r
Permalink Reply by Michael J Blane on June 24, 2009 at 11:19am
I have a pretty good relationship with the people where I bought it (Wastyn's).
I hadn't thought about warranty. Good idea.
It does look as if I went off a curb and bottomed the gear. Certainly don't recall doing that though.
Permalink Reply by Tank-Ridin' Ryan on June 24, 2009 at 1:19pm
LMAO!

joe said:
i dont bend mine. i just break them in to several peices. r
Permalink Reply by Michael J Blane on June 27, 2009 at 5:07pm
Thanks again to all.
I ended up taking it over to Wastyn's had a couple of other minor tweaks attended to. Took about 5 minutes and everything is fine.

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