SRAM Red front mech

broachboy

Greetings forum goers, I have an issue with my red(and my force on my 2nd bike) front mech that is causing much frustration. The issue is that when on the big ring the mech outer plate rubs against the chain on all but the top 5 sprockets of the cassette, and unlike my previous Shimano and Campag bikes there is no way to 'trim' the mech to stop the rubbing Anyone out there have any thoughts or ideas as how to put this issue right please ? :roll:

ck101

Google this, well covered in the past.

StillGoing

You can trim SRAM front derailleurs but it isn't the same as Shimano. When you've clicked up to the big ring, there is an intermediary click before the click to go back down to the small ring. This intermediary click effectively trims the front derailleur. However, if you tinker with the mech there should be no need to trim as SRAM FDs are designed to operate cross chained without interference.

simonj

If they are the later yaw ones there is no trim funcion and if setup ok should not rub.

gloomyandy

All of the above varies on which front mech and which shifters you have... The Yaw front mech should work over the full range of gears and the Yaw compatible shifter will not have any trim. Older front mechs may not work over the full range (but typically will rub only on the extreme of small/small when adjusted properly). The shifter for the 2012 red group had trim on the big ring and is described above. I think that some older Red (and possibly force) shifters had the trim on the small front ring (but I don't have any of those so not 100% sure).

I have bikes with Yaw/2013 Red and 2012 Red, the Yaw stuff works fine on all combinations, the 2012 has rub on small/small only.

broachboy

Brilliant, thanks for the replies. I will check what combo of levers and mech I have and post back

sungod

assuming there's not something broken, sounds like cable tension is too high, because pre-yaw red shifters have trim on the big ring

i.e. as if the tension was set with the shifter in the trim position, rather than the full tension position

release the cable, go through alignment/adjustment from scratch

StillGoing

sungod wrote:

assuming there's not something broken, sounds like cable tension is too high, because pre-yaw red shifters have trim on the big ring

i.e. as if the tension was set with the shifter in the trim position, rather than the full tension position

release the cable, go through alignment/adjustment from scratch

Exactly. Both my 2010 Force and 2011 Red shifters have trim function and the FD has no rub when cross chaining from big to large and vice versa.

broachboy

Thanks so much for your help and replies. Please see the pics of my levers and front mech below ...





Not sure to be honest what year the components are, but I guess they are pre yaw.

The reply from sungod sounds like it could be a possible, I only thought to myself yesterday that even on the small chainring the front mech cable was quite tight :roll:

sungod

broachboy wrote:

<...>
The reply from sungod sounds like it could be a possible, I only thought to myself yesterday that even on the small chainring the front mech cable was quite tight :roll:

if the cable is tight on the small ring, it's almost certain that tension is too high

fwiw i've got sram red of the same period, there's no rub at all on the big ring, even when cross chaining all the way, the only time there'd be some rub is on the small ring if i were to use the 2-3 smallest cogs (but i never cross chain on the small ring)

NANS295

madasahattersley wrote:

They are 2010-2011, and yes pre 'yaw.' Setting up those front mechs is something I'd get your local mechanic to do - they are made of titanium, so are notoriously rubbish at shifting (I've got one myself) but work ok if set up properly. I'd really recommend getting a newer 'yaw' one though. You've got a nice bike by the looks of things, and the £115 on the new mech will make her happier

I believe Sram only recommends the Yaw front derailleur as a complete system i.e. you also need to buy the newer shifters and chainset. I'm not 100% sure why though.

styxd

Get an old shimano mech (5600, 6600 or 7800) - that should cure your shifting issues.

NANS295

styxd wrote:

Get an old shimano mech (5600, 6600 or 7800) - that should cure your shifting issues.

Similarly I don't think you should mixed Shimano front derailleurs with Sram shifters. As far as I know it's due to Sram and Shimano shifters having different pull ratios.

styxd

NANS295 wrote:

styxd wrote:

Get an old shimano mech (5600, 6600 or 7800) - that should cure your shifting issues.

Similarly I don't think you should mixed Shimano front derailleurs with Sram shifters. As far as I know it's due to Sram and Shimano shifters having different pull ratios.

They work fine, aslong as it's the older "600" series. Shifts far better than my SRAM mech ever did.