Chain rubbing on front derailer

[thomas]

On my way back from a ride earlier I got cut up then grinded my gears a little bit. The chain is now rubbing on the front derailer when in the highest gear. If I push the gear changer all the way over this stops it rubbing.

I assume I need to adjust the derailer? From what I could see on the actually derailer there is a bolt that an allen key would adjust. This is behind the 3 front gears.

I don't have many tools with me at uni, I do have an allen key. Do I need to loosen the bolt and then readjust it so it doesn't rub then tighten it again? It seems a little tricky as it's behind the gears and the allen key have to fit through the 3rd and 2nd gears.

I'm a little worried that if I loosen it that it might ruin it in the other gears too. It seemed very tight when I had a quick play after getting back.

Any advice ?

 

[Smokin Joe]

There are two small screws on the outside of the mech that limit the travel to stop the chain overshooting. You need to slacken of the high gear limit screw, probably by 1/4 turn at the most. The screws may be marked H (High) and L (Low) but are not always. If not, when you are on the large chainring look carefully to see which of the screws is butting against the stop on the mech and that will be the one.

 

[thomas]

There are two small screws on the outside of the mech that limit the travel to stop the chain overshooting. You need to slacken of the high gear limit screw, probably by 1/4 turn at the most. The screws may be marked H (High) and L (Low) but are not always. If not, when you are on the large chainring look carefully to see which of the screws is butting against the stop on the mech and that will be the one.

Ah! I did see them when looking and did wonder about adjusting them too! Many many thanks...I'll have a go at adjusting them when I next use the bike

 

[Smokin Joe]

BTW, before you do that check the cable when the chain is on the small ring. If it has gone slack that may be the cause of the problem and retensioning will solve the problem. Apologies for not mentioning that first.

 

[Apeman]

Disaster struck when trying to remove bottom bracket on my Claude Butler Hybrid. Using a bottom bracket remover I stripped all the splines off obviously using too much pressure as the bracket was very tight. Where did I go wrong? The bracket holder seemed to be made from some sort of composite plastic. Now am faced with a trek to LBC and embarassing explanations.

 

[Paulus]

Disaster struck when trying to remove bottom bracket on my Claude Butler Hybrid. Using a bottom bracket remover I stripped all the splines off obviously using too much pressure as the bracket was very tight. Where did I go wrong? The bracket holder seemed to be made from some sort of composite plastic. Now am faced with a trek to LBC and embarassing explanations.

Are you in the right topic?

 

[thomas]

BTW, before you do that check the cable when the chain is on the small ring. If it has gone slack that may be the cause of the problem and retensioning will solve the problem. Apologies for not mentioning that first.

If it has gone slack, how would I retension? In a similar way to doing the screws? cheers.

 

[Smokin Joe]

If it has gone slack, how would I retension? In a similar way to doing the screws? cheers.

You probably have a barrel adjuster on the downtube through which the cable passes. Just screw this anti-clockwise until the slack is gone. Alternatively you can unclamp the cable at the mech and pull it tight with a pair of pliers while you tighten the clamp bolt.

 

[Angelfishsolo]

+1 Thomas, did you get your front mech problem sorted out? What was the cause of it in teh end?

You probably have a barrel adjuster on the downtube through which the cable passes. Just screw this anti-clockwise until the slack is gone. Alternatively you can unclamp the cable at the mech and pull it tight with a pair of pliers while you tighten the clamp bolt.