Gears skipping

[jukka]

Ok i have adjusted all my rear derailer gears and they chnage perfectly.Now I am in the middle of adjusting the front derailer which has 3 sprogs on it.The smallest sprog i started with and runs good. i try to change to the 2nd sprog (middle one) nothing happens but i can change up to the 3rd sprog no problems.

When I am on the 3rd outer sprog it changes down to the 2nd sprog no problems from the 2nd sprog it wont change to the 1st sprog. I have tried tighting the cable from the shifter on the handel bars and also tried adjusting the derailer guide but throws every thing out. I have set it up so its 3mm above the outer sprog as suggested anybody got any tips on how to fix this problem???

 

[simon_brooke]

OK, to start with, put the chain onto the middle cog at the back and the middle cog at the front, obviously with both shifters in the appropriate setting. Adjust the cable tension so that the front derailleur is exactly centred on the chain (same amount of space both sides).

Now, while pedalling (helps to have the bike on a work stand), change down on the front shifter. If the chain does not drop onto the small ring, click the shifter back to the middle position, loosen the low limit stop screw on the front derailleur (usually marked with a '-') half a turn, and try again. Keep doing this until the chain changes down to the small ring at the front easily every time. If it falls off on the inside of the small ring you have backed off the low limit adjustment screw too far, so tighten it half a turn.

Now, change onto your largest (lowest gear) cog at the back, and repeat the middle to small change at the front, adjusting the low limit stop screw as before. This should only need a very, very small adjustment if any at all. I've seen some bikes where it's impossible to get this particular adjustment right (i.e. changing down at the front when the rear is already on the largest cog), but on most you can. If you can't, then you will need to fit a dog-fang to prevent the chain falling off on the inside.

Once you have the middle-to-small adjustment right, again put the chain onto the middle cog at the back and attempt while pedalling to change into the big ring at the front. If it won't go, loosen the high limit stop screw (usually marked '+') half a turn and try again. If it falls off the outside of the big ring you've gone to far, so tighten the high limit stop screw half a turn at a time until it no longer does.

Once that's working fine, shift the chain onto the smallest cog at the back and again repeat the middle to largest change at the front. Again, you should only need to make very, very small adjustments at this step, and you should be particularly wary of the chain overshifting off the outside of the big ring.

Once this adjustment is satisfactory you're done for the front.

 

[spandex]

+1

Simon that is a good right up

 

[jukka]

Thanks simon appreciate the awesome advice will give it a go tomorrow !