Bicyclists: Trek 4100 won't go into 7th gear. Any idea why?

[dak125]

I don't want to get this thing repaired if I don't have to. Basically it won't go into 7th gear while pedaling, it will still be in 6th even though it says 7th. But, if you stop pedaling it may eventually lock into 7th. The guy at the bike shop said something about a frame adjustment or something, if it's something easy I'd rather do it myself. Any ideas? Or do you know of any good cyclist forums?

Thanks.

 

[Brutuskend]

It won't drop into the small cog in the rear?

 

[Don Vito Corleone]

Your terminology is confusing to me, since everyone has a different notion of what "7th gear" means. Are you trying to shift into a smaller cog or a larger one?

In general, the most common cause of rear shifting problems is cable stretch. When the cable stretches, the bike becomes resistant to shfting into a lower gear. You can adjust this with the barrel adjuster on the rear derailleur (which you turn counterclockwise to tighten the cable).

 

[Sukhoi]

Yeah I assume he means 7th gear as in one of the smaller cogs on the rear.

 

[The Stigenator]

your drive train needs aligning.. check teh cables and lube it and check the play.

 

[Brutuskend]

Originally posted by: DonVito
Your terminology is confusing to me, since everyone has a different notion of what "7th gear" means. Are you trying to shift into a smaller cog or a larger one?

In general, the most common cause of rear shifting problems is cable stretch. When the cable stretches, the bike becomes resistant to shfting into a lower gear. You can adjust this with the barrel adjuster on the rear derailleur (which you turn counterclockwise to tighten the cable).

Or the stops on the dérailleur are set too tight.

Or the dérailleur tab on the frame is bent.

Or you have rust/dirt in the cable housing and it's keeping the cable from sliding smoothly.

 

[dak125]

Holy big words! I should mention that I'm quite the bike terminology noob, so, I don't have a clue what a derailleur is or most anything else you guys said. Is there a "bike map" that points out the parts of the bike so I can put 2 and 2 together? Thanks!

 

[Brutuskend]

Here

 

[notfred]

Originally posted by: dak125
Holy big words! I should mention that I'm quite the bike terminology noob, so, I don't have a clue what a derailleur is or most anything else you guys said. Is there a "bike map" that points out the parts of the bike so I can put 2 and 2 together? Thanks!

Just pay your local bike shop $5 to adjust it. It's a 5 minute adjustment. I don't feel like defining all the different parts of a bike over the internet, though.

You can try reading this, it expalians a lot about derailluers

 

[dak125]

Originally posted by: Brutuskend
Here

Thanks for the link. I'll look at it more in depth tomorrow. From a quick glance I didn't see the "barrel adjuster". Is it on the rear derailluer? Perhaps a hex nut type deal? Thanks for the help. I'll respond tomorrow.

 

[Brutuskend]

Originally posted by: dak125

Originally posted by: Brutuskend
Here

Thanks for the link. I'll look at it more in depth tomorrow. From a quick glance I didn't see the "barrel adjuster". Is it on the rear dérailleur? Perhaps a hex nut type deal? Thanks for the help. I'll respond tomorrow.

Yes, it under where the cable housing goes into to the read dérailleur.
There is also another barrel adjuster on the shifter itself. (99% of the time at any rate)