Limited chain rattle - front mech.

merlin321

Hi all,
I have a 9 speed triple on an scr2.
The largest and smallest rings have a full range of gear selection with no rubbing or slipping anywhere. On the middle ring being in gears 1-5 is fine, but going into 6 the chain begins to rub on the front mech and 7,8 and 9 are rubbing continuously.
Changing up and down through any gear is smooth and easy so I don`t want to go tinkering and censored up what I`ve already got, but the rubbing noise is spoiling an otherwise great ride.
Any ideas?

Many thanks.

John.T

Check the the mech cage is parallel to the big ring. If it is angled in at the back you will get this. Check that the cable is fitted correctly to the mech. If so then you need to use the adjuster to slacken the cable until the problem goes away. You may need to compromise somewhere.

japsy

merlin321 wrote:

Hi all,
I have a 9 speed triple on an scr2.
The largest and smallest rings have a full range of gear selection with no rubbing or slipping anywhere. On the middle ring being in gears 1-5 is fine, but going into 6 the chain begins to rub on the front mech and 7,8 and 9 are rubbing continuously.
Changing up and down through any gear is smooth and easy so I don`t want to go tinkering and censored up what I`ve already got, but the rubbing noise is spoiling an otherwise great ride.
Any ideas?

Many thanks.

There should be trim selection when in the middle ring. This should allow you to move the fd to stop chain rub on the extremes. So you effectively have 4 positions for your index.

Try moving on to big ring (does the lever not allow you to move further
?), then click once to go down to middle. Click down again and the fd will move inwards but the chain will still stay on the middle ring. Click one more and then it will drop to your granny.

Shimano tech docs document this feature.


I have this on my scr2 2007.