In the 2007 Sram Technical Manuel it states;

The left hand shifter offers a trim
function for the front derailleur to allow
the chain running smoothly on the
small chainring in extreme positions.
(Shift position 1 and 2 is for the small
chainring. Shift position 3 is for the large
chainring.)

I don't understand what this means, after shifting into the big ring, if I move the shift lever again it only shifts back into the small ring. can anyone tell me how to adjust the trim?

In the 2007 Sram Technical Manuel it states;

The left hand shifter offers a trim
function for the front derailleur to allow
the chain running smoothly on the
small chainring in extreme positions.
(Shift position 1 and 2 is for the small
chainring. Shift position 3 is for the large
chainring.)

I don't understand what this means, after shifting into the big ring, if I move the shift lever again it only shifts back into the small ring. can anyone tell me how to adjust the trim?When you're in the inner ring and shift toward the smaller sprockets on the cassette, the chain clips the cage slightly in the 3rd and sometimes 4th position. If you do a small click on the L/H shifter the cage moves enough to stop this. It is a myth that Force/Rival have NO trim, rather they don't have the extra one Shimano has where one can nudge the cage back a smidge when in the big ring and 3rd to largest sprockets. Sram does not need this as the cage appears to be a little wider.

When you're in the inner ring and shift toward the smaller sprockets on the cassette, the chain clips the cage slightly in the 3rd and sometimes 4th position. If you do a small click on the L/H shifter the cage moves enough to stop this. It is a myth that Force/Rival have NO trim, rather they don't have the extra one Shimano has where one can nudge the cage back a smidge when in the big ring and 3rd to largest sprockets. Sram does not need this as the cage appears to be a little wider.

I was under the impression that I could adjust the cage while in the large chainring. (just like Shimano) I now understand the trim function Sram talks about is for the small chainring. ( Too much red wine last night to read properly:crazy: )

Thank you for the excellent explanation, :thumbsup:

It takes some tweakage but what you want to do to avoid needing/wanting trim in the big ring is set the high limit screw on the FD conservatively so the chain is quite closer to the outer cage when you're in the big chainring + smallest cog, this will maximize the use of the wide cage to avoid having rub in the big chainring + larger cogs.