Warped Chain Ring
 

I read the article on fixing a warped chain ring in Zinn's book. My 53 Tooth ring is driving me nuts because in one gear in particular I cannot trim to stop chain rub as the warped part comes through the derailleur. At least I think it's warped. Anyway does anyone have any tips on straightening out a chain ring? Does it really work or should I just get a new one? Thank you.

You could try dismounting the chainring, then rotating it to a different spot on the spider 2 or 3 holes away from its current location. That could lessen (or worsen) the warped condition. Park tool makes a special spanner wrench with a skinny slit that allows the mechanic to lever the bent chainring (or even the offending spider arm of the crank) into alignment. I had an experienced mechanic at my LBS do it though - it only took a couple of seconds to a trained eye and my front derailleur was no longer rubbing all over the place :) .

Park has just come out with a new tool to bend disc brake rotors. I bet the same tool would work just fine to bend a chainring.

That's interesting. Because when Disc brakes first came along, I used the Park chain ring tool to straighten bent rotors. Still do. But thanks, I'll have to look into one. The Morningstar disc tool was one of the next new tools I was going to get. But if the Park one is cheaper, I might try it.

Back in the 90's I was sure I had every tool a bike shop needed to fix bikes. Wrong. Since then I guess I have invested at least another $1000 to $1500 in tools. And that's okay, I love tools.

I am no doubt getting less smart in my old age, but do you have a part number for the Park chain ring tool? I have just looked on the Park website and cannot find it. Back in the day, I just wrapped the jaws of a crescent wrench with some masking tape, clamped onto the ring and gently bent away. I did not know that Park makes a tool for the purpose.

I cannot find the park chainring tool listed either. I bought it in the 80s. But Bicycle Research still makes one with a double slot. One narrow, and one not so narrow. It's part number is LC-1. I have one of those also, and use it more often than the Park. Wow! I just looked up the wholesale price and they have become way more expensive than the $5 or so I spent on it back in the 80s. I don't know what the MRSP is but I would expext you would have to pay over $20 for it. Maybe closer to $30. The Third Hand is bound to have it. Or if you have access to Quality, part # TL1001.

This just in: the Park disc brake rotor truing tool does not work on a chainring. I had my MTB out tonight, and I was bending the rear rotor back into true. I tried it on a Truativ chainring, and then on the Ultegra chain ring on my two road bikes. The slit in the Park brake tool is too narrow to accommodate a chain ring. Back to the crescent wrench for me!