Front derailleur problem

bianchi007

My ultegra front derailleur seems as though it's range of motion is less than it should be. When it was in the big ring and 11 sprocket the chain was Rubbing and the limit screw was loosened fully, I tightening the cable and now it rubs when in small ring and the 25 sprocket, again with limit screw loosened fully. This is a new bike anyone know what's wrong or how to fix this?

lescol

Sounds like the cable is slightly too tight now! Follow the instructions in the youtube clip and you should be sorted, it's important to have the limit screws adjusted correctly.

Type 17

With a 9+ cassette, the correct placement of the Front Deraileur (FD) cage is very important (more important than with up to 8 sprockets) - if it is too high, like the one in the initial shot of the video above, or if its sides are not perfectly parallel to the chainrings, then the cage will rub the chain when the smaller or larger sprockets are used.
Note that with some bikes (short chain stays, 9+ cassettes, triple chainrings are factors) it may not be possible to adjust the FD to avoid some rubbing in some gears, but usually only in ratios that you shouldn't use due to cross-chaining.

To set up a FD from scratch, first set the height and cage-straightness, then the limit-screws, and finally the cable tension.

Xpro

Is this the new 6800 ultegra? They can be tricky to adjust..

If so below applies: ( taken from cycling forum, not my article)

Here's the Shimano 6800 set up pdf aswell
http://www.google.co.uk/url?sa=t&rct=j&q=&esrc=s&source=web&cd=1&ved=0CCMQFjAA&url=http%3A%2F%2Fsi.shimano.com%2Fphp%2Fdownload.php%3Ffile%3Dpdf%2Fdm%2FDM-FD0002-03-ENG.pdf&ei=rmGBVOSiC4T0UMXKgvAP&usg=AFQjCNHD75RkTeFa7zzb0Uvirl-hYXh92w&bvm=bv.80642063,d.d24&cad=rja

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The ultegra 6800 front derailleur has a trim function on both the big AND the small ring. So big lever and little lever. (if you dont know what the trims functions are - they are lever clicks that allow you to move the cage slightly to eliminate chain rub)


To set up the 6800 front derailleur correctly an inline barrel adjuster should be used. It will make set up much easier. if you dont have one, install one. Make sure it is screwed all the way in too, before starting.

Start off with the outer limit screw screwed out (the limit screw closest to the big ring)

Start over. undo the cable

When clamping the front derailleur to the frame make sure the gap between the big chainring teeth and front derailleur cage is 2mm.

Toe the cage in slightly (around 4mm) when clamping. Then use the support bolt to align the cage with the big chainring. The support bolt is a small screw that pushes up against the seat tube to add stiffness to the front derailleur when shifting. It also moves the front cage outwards as you screw it in. See page 8 of the pdf below
http://www.google.co.uk/url?sa=t&rct=j&q=&esrc=s&source=web&cd=1&ved=0CCMQFjAA&url=http%3A%2F%2Fsi.shimano.com%2Fphp%2Fdownload.php%3Ffile%3Dpdf%2Fdm%2FDM-FD0002-03-ENG.pdf&ei=rmGBVOSiC4T0UMXKgvAP&usg=AFQjCNHD75RkTeFa7zzb0Uvirl-hYXh92w&bvm=bv.80642063,d.d24&cad=rja

So first , with the cable de-attached. Put the chain on the small front ring and 25t (or biggest) back cog. - Make sure to click the downshift lever into its lowest position.

Adjust the inner limit screw (closest to the frame on the front derailleur) so the gap is 0.5mm from the chain and the front derailleur's plastic plate,and not rubbing on the chain.

Clamp the cable (pull the cable fairly tight with pliers and clamp). Then shift the chain onto the 11t cog (or smallest) at the back, and shift the front onto the big ring. (if it doesnt shift up - add more tension by loosening the bolt and pulling more cable ,then re-tighten the bolt). Now when in the big ring there should now be some chain rubbing on the cage if you spin the cranks.

Then wind the inline barrel adjuster (adding more cable tension) until there is a 0.5mm gap between the outer cage and chain, and no chain rub. Look down at the front derailleur cage as you do it, and spin the crank until the rubbing stops. At this point it is crucial that the front area of the front derailleur cage is parallel to the chain plates. You can fine tune the angle with the support bolt.

Then wind the outer limit screw in until it touches the stop. (If the outer limit screw is screwed in too much it wont shift up - this is why you screw it out at the beginning.)

Next shift the front down onto the small ring and the rear on to the second to last smallest cog. Then click into the front small ring trim position. now whilst in the trim position,add a little bit more tension with the barrel adjuster. This will eliminate any slop in the trim and make it more positive to click.

Now it should all be set. Check all gears and trim settings. Make sure the chain isnt being thrown over off the big ring.

If you find the small ring trim click isnt very positive. Start over and try the second cable routing tab position. (remember to wind the barrel adjuster in again before starting.)

There will always be rub in the big/big combo. This is cross chaining.

pprendeville

The Arts Cyclery videos are good also. Took the text from their video ages back.

How to adjust a Front Derailleur
1: Parts include:
- lower (inner) limit screw (nearest the frame)
- upper limit screw (furthest from frame)
- cable tension anchor (coarse tension adjustment)
2. Adjust position of derailleur.
Loosen cable tension anchor.
Bottom of derailleur cage needs to be 1-3mm from top of big chainring and also parallel to it.
3. Barrel adjuster needs adjusting all the way CW (releases tension in cable and allows for adjustment later)
4. Shift to small chainring and largest sprocket to set inner limit.
- Inner plate of derailleur cage needs to be as close to chain as possible without touching it).
- To do this you must tighten the inner limit screw (turn CW). Note: helps to pull out deraileur with your hand so it's not up against the stop, making the screw easier to turn.
5. Adjust cable tension.
- Loosen cable anchor.
- Pull it hand tight.
6. Shift into the big ring.