Front Mech issues

[scottie7275]

Hi,
Not cycled for a long time but recently bought a SCOTT AFD Comp second hand off Facebook.

I got it cheap as there was a problem with the gear shifts. I have replaced all cables and cleaned off and lubricated both front and rear mech and both are now moving freely.

However, the front mech does not seem wide enough? By this I mean if I put the rear on the bottom cog and adjust the front to allow clearance for the chain to the outside, when I shift the rear to the largest cog the chain scrapes on the inside of the the front mech.

I have tried to adjust every which way but cannot seem to get it right? Is it possible that the front mech is the wrong one for the bike or am I missing something?

Thanks for any help.

Scott

 

[Deleted member 1258]

https://www.parktool.com/blog/repair-help/front-derailleur-adjustment

The link is to the park tools front derailleur adjustment guide, check what you've done against the guide and see if you can see where you went wrong.

 

[C R]

Hi,
Not cycled for a long time but recently bought a SCOTT AFD Comp second hand off Facebook.

I got it cheap as there was a problem with the gear shifts. I have replaced all cables and cleaned off and lubricated both front and rear mech and both are now moving freely.

However, the front mech does not seem wide enough? By this I mean if I put the rear on the bottom cog and adjust the front to allow clearance for the chain to the outside, when I shift the rear to the largest cog the chain scrapes on the inside of the the front mech.

I have tried to adjust every which way but cannot seem to get it right? Is it possible that the front mech is the wrong one for the bike or am I missing something?

Thanks for any help.

Scott

That sounds like normal behaviour, you are normally advised not to ride large large or small small, as the chain angle is not ideal. Think of the scraping as the bike telling you to use the small chainring.

 

[Globalti]

If you cross the chainline enough to cause rub you will wear out the chain very fast because you'll be asking the links to change direction four times with each revolution.

 

[winjim]

Just because cross chaining is not advisable doesn't necessarily mean that you shouldn't be able to do it. Does the front shifter not have trim?

 

[Mike_P]

I have the same issue, seems some front derailleurs are just not wide enough to cope with cross chaining issues so as @C R comments use it as an alert to swap to the other chainring - happens on both the small chainring - smallest cog and largest chainring - largest cog combinations.