Bicycle Mechanics - Grind off chainring pins for fixed gear?

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kit
04-23-09, 01:54 PM
I found a 52t chainring at the LBS that I'd like to put on my fixed gear. The ring has shifting pins on it, and my chainline already isn't perfect. Is there any reason I couldn't just grind or file the pins off?


LarDasse74
04-23-09, 02:12 PM
Chainring pins are only useful if you have a bike with a front derailleur.

However, your description leads me to think that your chainline is bad, your drivetrain is noisy or not smooth, and you think grinding the pins off will help smooth it out... in fact, the pins are likely having no effect on the drivetrain, and the only fix for your problems is to get the chainline correct.

Good luck!

AEO
04-23-09, 02:21 PM
no need, the pins don't add any sort of noise.
but the shaped teeth don't help the longevity.
if you haven't bought it already, why don't you go look around for some older (5~7sp era) chainrings with no pins or ramps?


kit
04-23-09, 02:43 PM
I can't seem to find any 135 BCD chainrings without pins. (Except for 1/8" ones, which I'm trying to avoid.) Do I just need to be more patient? Do they come up on ebay?

LarDasse: I bought a complete bike with a chainline that looks to be off by about 7.5 mm. It's actually completely quiet-- just not at the gear ratio that I would like.

kit
04-23-09, 02:49 PM
And to further clarify, I'm concerned about the pins encouraging the chain to jump off, not the noise.

DaveSSS
04-23-09, 02:58 PM
The pins only aid the shift up from the little ring. They have no effect on the function of the chain once it's on the big ring.

tellyho
04-23-09, 06:55 PM
7.5 mm

Seriously? That's WAY too much of a difference. A silent drivetrain will not be much comfort when you suck the chain and faceplant. And I'm a pretty relaxed guy on the chainline front. You need to fix that.

As far as the pin is concerned, there's no way it will affect anything, as your chain will never get anywhere near it.

kit
04-23-09, 08:42 PM
Thanks for all of the help. I guess I won't get to go to the Darwin Award ceremony after all.