# Chain grind - front derailleur adjustment



## oyeflaco (May 8, 2006)

Is it possible to adjust the front derialleur so you can use any gear in the rear cassette without grinding the chain? 

I have a Jamis Quest I bought used, it's all 105 except an Ultegra double crank. I believe the bike came standard with a triple--would you expect that to cause any problems? It seems I can set the front derailleur to allow me to use 6 of the 9 gears without grinding (on the smaller front sprocket). Is this normal? Thanks!


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## ericm979 (Jun 26, 2005)

This is normal. Your front derailleur lets you 'trim', or change the cage's position without shifting, to deal with this. If you are on the smaller cogs (higher gears) and the chain is rubbing the cage, try moving the big lever but not far enough to make a shift. It should make a faint click and hold the cage farther out so the chain does not rub. If you are in the large cogs (low gears) and it's rubbing, click the small lever to get the cage all the way over to the left. It may be easier to see this with the bike on a stand or held up while you pedal. Once you know about it, it soon becomes automatic.

Using the smallest cog with the small chainring, or the largest cog with the large chainring, is "cross chaining" and should be avoided because it'll wear the cogs and chainrings out faster. If you accidentally shift into a cross chain combination, it is not the end of the world (unless your chain is too short!), just shift back.


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## oyeflaco (May 8, 2006)

Eric,

Thanks for the reply. I definitely realize I shouldn't cross the chain, and that's actually why I had this concern. If I shift into the large chainring before about 22 mph, I will be crossing the chain pretty severely. But to get to 22 in the small chainring I have to be on basically the top gear, which is fine, but makes it impossible to get to the lowest gear for hills without grinding. 

I've noticed that trimming can help when I'm in the larger chainring, I had assumed this was because the bike was a triple and is now a double. I had attempted to adjust the front derailleur to work with all the cassette at one setting, but now I see I can trim to use the whole cassette.

Thanks for the advice, now I just have to wait til I get home to try it out...


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## Kerry Irons (Feb 25, 2002)

*What gears?*



oyeflaco said:


> If I shift into the large chainring before about 22 mph, I will be crossing the chain pretty severely. But to get to 22 in the small chainring I have to be on basically the top gear, which is fine, but makes it impossible to get to the lowest gear for hills without grinding.


What gears are you running? 22 mph at 90 rpm with a 53 chain ring requires a 17t cog in the back. That is hardly cross chaining! Unless you're running an 11-21 cassette, this should not be an issue at all. And if you actually needed an 11-21, then we wouldn't be haiving this discussion.

And, as to your original question, it should be obvious that there is no adjustment of the derailleur that can keep the chain from rubbing on the large chain ring - the two issues are completely unrelated. The chain would rub even if there were no front derailleur present.


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## mpeters25 (Apr 26, 2006)

I too was having this same question when I found this post. Funny, because I figured out the action for trimming but never knew it was an intentional and required action. Since I've started viewing this forum I can't believe the things I learn everyday. Here I thought it would be as easy as riding a bike! (I know, I know bad joke)

Matt


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## oyeflaco (May 8, 2006)

Kerry Irons said:


> And, as to your original question, it should be obvious that there is no adjustment of the derailleur that can keep the chain from rubbing on the large chain ring - the two issues are completely unrelated. The chain would rub even if there were no front derailleur present.


When I said "It seems I can set the front derailleur to allow me to use 6 of the 9 gears without grinding (on the smaller front sprocket)," I was referring to the chain rubbing on the derailleur when I'm in the small chainring. I definitely could have worded that better.

As to your question about gearing--when I get home I will figure out what the gears are. Maybe the guy I bought it from put something ridiculous on there, ha.


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