Bicycle Mechanics - Hard to shift to biggest ring
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I have a slight problem. After I cleaned my entire drive-train I noticed that my front derailleur shifting was not as smooth as before so I decided to try and tune it, this is where the problem starts.
I completely messed up the tuning and now can not get smooth shifting at all. I have have googled till my fingers bleed and have tried to follow countless videos on youtube, ehow etc and still no joy. I did manage to tune the front derailleur so that I can shift to each ring but, when I try to shift from the middle ring to the biggest it shifts but it feels like there is so much tention that I may snap the shift lever if I keep riding like that. Also, when I shift back, biggest to middle, it snaps back so quick it sounds unhealthy.
If it wasn't for the high tention it would be fine as everything is aligned and every gear is accessable. Please help, it has taken me 9 hours to get this far and don't really want to play around with it again until I'm a little wiser.
Any ideas hiow to relax the tension without messing the whole thing up again ?
Thanks for reading :o
might be low cable tension.
does your shifter have any cable tension adjuster barrels?
you have to yank on the FD cable quite hard to pick up all the slack when first attaching it to the FD. Something an inline cable adjuster can easily address.
Did you change the position of the outer limit screw, or cable tension adjuster? (if you have one).
From your description, it seems that the lever is fighting against the limit screw, and you need to back off the limit or cable tension adjustment. Which really depends on what other problems there are. If it shifts, but just needs too much tension, it's more a cable issue, if it's sluggish to shift, it;s more likely the limit is keeping it from moving out enough. Since it's easier, I'd try the limit screw first, & back it off by degrees, and see if things improve.
Other possibilities are that the entire FD is out of position and/or the cage isn't parallel to the chainrings.
BTW- on non-index front derailleurs cable tension doesn't matter as long is it's close enough for the FD to function within the travel of the shifter, but index fronts should have an adjuster like the RD. If yours doesn't consider buying an inline adjuster to make fine-tuning easier. It shouldn't take an hour to set up a front derailleur, never mind nine. If you need a review try the park tool site for a decent tutorial.
Yes they do. I tried twisted the barral but that only seems to move the derailleur slightly and does nothing to make the shifting easier. Felt under the tube when riding and thetension of the cable is very high. When I was trying to fix the problem I noticed that when the chain was on the smallest ring, there was so much slack on the cable it was hanging. I undone the nut and took the slack off but did not pull the cable hard, just took the slack off.
I did mess around with both limit screws aswell if it makes any didfference.
06-02-10, 03:27 PM
If you have done all that I very much doubt that we are going to be able to help you here, especially with info like "I did mess around with both limit screws." You need a good mechanic who can see what is going on and correct it.
Since you moved the limit, I'll go with my theory that the outer is a bit too tight. Test and adjust it by shifting without using the lever. leave it in the slack (low gear) position and shift by directly pulling the bare wire away from the frame. You want to adjust the outer limit so it makes the shift smoothly without going beyond, or hitting on the crank arm. Repeat the process to set the inner limit for shifting to the innermost chainring.
Now that the range of travel is established adjust the cable tension with the barrel adjuster so it shifts according to the lever position. If you don't have a barrel adjuster, consider an in-line one for next time around, but in the meantime, disconnect the wire and take up the slack in low gear and that should get you close to home.
If when you then shift to high the FD doesn't move all the way to the limit, try this trick for taking up more slack. Holding the cage our a bit against the spring turn the inner limit in exactly two turns. Pull up the slack and attach the wire, then turn the limit back to the original position. If that now makes the cable too tight, repeat but this time with only one turn on the inner limit.
Im doing as you said, pulling on the bare wire but I don't see how adjusting the limits help. It seems to shift no matter where I let the limits to.
This may or may not be helpful, but I had a similar sounding problem recently with a double ring setup and it turned out that the little plastic piece on the bottom of the bottom bracket where the cable feeds through was very slightly misaligned and it was causing the cable to drag a bit on the edge of that piece before going up to the front derailleur.
I don't believe this but I finally fixed the problem and just finished tuning. Gears shift quick and smooth. I am not sure if it was the same problem as what you discribed Andy K but sounds very simular :lol::crash:
I never noticed before but the cable wraps around a piece of plastic before being secured by a nut, the cable had slipped off and that was waht was causing the high tension. Such a small thing causing so much trouble :crash:
I can't believe you posted that Andy K just as I noticed the problem too :lol:
Not sure what damage I may have done shifting gears while the cable was wraped around a pivot point but I probably need some new limit screws, I wore the heads abit doing so much adjusting and probably need some new cable as it is beginning to fray now. Apart from that all is fine now and I am really happy.
Thanks for all the help people.
Oh, and I was following all the step by steps in earlier google searches and following the adice in online videos correctly but no amount of adjusting was going to make that mess run smooth.
At least I learned a lot about how to adjust a front derailleurs today, knew it couldn't have been so complexed. Thanks again all :D
06-02-10, 05:36 PM
I remember have tried peyote back in the day in my country before the stoners made it an extinct plant in the desert. good stuff anyways :D
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