Problems with a triple

redddraggon

My nephew has just got a road bike with a triple. Ive been trying to get the high and low stops right on the front derailler correct (which I think they are now), but the chain regularly drops off the inside when shifting to the granny ring (and even when shifting to the middle from the granny apparantly).

To try and prevent it dropping off, I've set the derailler so that it rubs slightly in the 30-25 combination - but the chain is still dropping off.

Having never had a triple myself - is there anything conceptually different between setting up a double and a triple?

I won't be recommending a triple to beginner again at this rate.

MartinJ

Seems strange. My triple is 100% reliable. High and low stops set up just like a double - cable tension adjusts the position of front mech for middle chain ring.

Only thing I can think of is that the rear mech is having difficulty taking up the slack in the chain. Possible things to consider:

Has is got a long cage rear deraillieur? (Essential)

Is the chain too long?

Does it make a difference which which rear sprocket its on when you change to the inner ring?

Good luck.

hammerite

redddraggon wrote:

My nephew has just got a road bike with a triple. Ive been trying to get the high and low stops right on the front derailler correct (which I think they are now), but the chain regularly drops off the inside when shifting to the granny ring (and even when shifting to the middle from the granny apparantly).

To try and prevent it dropping off, I've set the derailler so that it rubs slightly in the 30-25 combination - but the chain is still dropping off.

Having never had a triple myself - is there anything conceptually different between setting up a double and a triple?

I won't be recommending a triple to beginner again at this rate.

don't know what they are called, but you could try fitting one those ring things with a nipple just below the grann ring, to push the chain back on if it trys to slip off.

redddraggon

A dog fang, thanks for that forgot about them,

hammerite

cool name

Another question about this. I've adjusted my triple recently as it was out, think it got knocked.

It rubs on the extremes opposites as you'd expect, but it seems to rub on more gears than it should. In the granny ring I can probably only use the four largest rear rings. The others rub like mad. On the top ring I can only use the four smallest rear rings without rubbing. On the middle ring I can use the 5 smallest rear rings without rubbing (I'm sure I could use all before on the middle ring).

If I adjust it any where away from the current setting then the chain usually doesn't engage up or down properly. Any ideas?

Shimnolo

Try my method. I take the bike to my local dealer and tell him it's playing up. He chews on the end of his pencil for a while, then scratches his head as I describe the symptoms.
When my uncertain voice tails off into embarrassed silence he stops scratching and points to a new and very shiny bike hanging on the wall. I then give him my credit card and ride home on a fully-functioning machine.

Works every time.