Triban 3 chain noises

[Kookas]

My drivetrain makes a regular click noise on the smallest cog. I took a little look and one particular tooth on the smallest cog keeps hitting the bottom of the walls of the links as they leave the second guide wheel, which then holds the link up away from the tooth.

The click comes after the link slips over the tooth, when the chain subsequently 'snaps' back down onto the next tooth. It's a regular click as it happens every time a link passes over that tooth.

It seems odd that the tooth might be bent. It is the smallest cog, so could it be that the maximum isn't set right? I've tried loosening the H screw without luck.


View: https://www.youtube.com/watch?v=ZdmNJR6Q-Qc&feature=youtube_gdata_player

 

[fossyant]

Stiff link on the chain ?

 

[BimblingBee]

I'd try loosing the cable (may 1/4 of a turn) looks like more of an indexing issue rather than stiff link as it's every revolution of the cassette rather than revolution of chain.

Sheldon is your friend too... http://sheldonbrown.com/gearing/index.html or look up park tools website.

 

[Kookas]

I looked at those sites, but found them pretty cryptic. Also, I'm missing two gears - I can't shift into my two largest, and three of my 'gears' are the same cog (the smallest). How can I move the derailleur towards the wheel?

Apparently I need to tighten the cable by turning the barrel CCW, but that loosens the barrel - and it ends up coming off altogether before I get my largest gears back.

 

[BimblingBee]

From what you've described you need to increase the tension on your cable to the rear mech. At the moment the first 2 or 3 'clicks' from the shifter (When you are in the lowest gear) is taking up the slack. When you get to the top you have run out of 'clicks' so are missing those gears. The H/L stops may also need adjusting.

Basically it is a Indexing issue and you need to start from scratch. Its easy to fix but if you can't then your only solution would be get a mate who can or take it to a bike shop. Cost is 10-15 quid, but it does depend on where you live.

Ps My first post was wrong as I didn't have the full details. This post is correct!

 

[subaqua]

or use the manufacturers info attached - and can be downloaded for free from techdocs

 

[Kookas]

I fiddled a bit more, and now have my full range of gears back. Basically, I undid the cable by the nut and there was still a very slight amount of slack in it. Pulled it taut and did it back up, then tightened up the barrel adjuster a small amount. On top of that, the original issue I mentioned (tooth hitting the links) is also gone. Thanks for your help guys.

 

[HovR]

I looked at those sites, but found them pretty cryptic. Also, I'm missing two gears - I can't shift into my two largest, and three of my 'gears' are the same cog (the smallest). How can I move the derailleur towards the wheel?

Apparently I need to tighten the cable by turning the barrel CCW, but that loosens the barrel - and it ends up coming off altogether before I get my largest gears back.

Your gears need completely resetting as the cable tension is too loose.

I'm assuming your Triban has 8 gears here. If it's more, replace 8 with your highest gear.

1. Start by putting your chain into gear 8, your smallest cog.
2. Now put your shifter into gear 8, your highest gear position.
3. Wind the barrel adjuster so that it is pretty much all the way in (turn clockwise).
4. There should now be a lot of slack in the cable. Undo the anchor bolt which holds the cable to the derailleur enough to allow the cable to move freely.
5. Pull the cable as taught as you can (making sure all outers are properly seated in the cable stops on the frame) by hand and then tighten the anchor bolt nice and tight so the cable can't move.
6. Now test the gears. if the gears are slow moving on to a larger cog, then unscrew the adjuster barrel a quarter of a turn at a time until the gear shifting is nice and smooth.
7. If you unscrew the barrel adjuster too much then it will become slow when shifting in to smaller cogs. Simply screw the barrel adjuster in, quarter turns at a time.

Assuming there is nothing else wrong with the bike (i.e. worn cables) then that will get your shifting back to normal.


Edit: Cross posted with you, sounds like you did pretty much exactly the right thing! Good to hear you got it working again.