Front Derailleur Problems, please help!

lukebennett

Hi,

Since about Wednesday last week my front derailleur has been malfunctioning, I suspended my bike, and have been fiddling with it ever since, I have now spent countless hours on it.

It is a compact crankset so only has two gears on the front, I started from the start, so I set my derailleur up the correct height from the chainring, and positioned it parallel, I then set my lower limit which worked fine. After slacking off the adjusting barrel all the way I pulled the inner cable finger tight and screwed it on the derailleur. Next I shifted up a gear, which seemed to work fine, so I set the outer limit screw to what was recommended, and then shifted down again, but then, when trying to shift up again it wouldn't shift up. So I assumed it must be down to the outer limit screw being too tight, so I loosened that, but then the chain actually just falls into the pedals, let alone it taking ages to actually shift up. So I thought I'm going to have to screw the outer limit screw slightly in. But then it wouldn't shift up at all.

So the problem I'm having is, if I want it to shift up, the chain will have to fall into the pedals, or otherwise, I can't shift up. I'm doing really minor adjustments but every time there is enough room to push the chain up to the higher gear, the chain is just falling into the pedals. Is there something wrong with my derailleur? Or am I just being really stupid? because I'm riding my bike exactly the same as before and it is not working like before. ha.

That is the question I would like asked anyway, because today a friend of mine recommended a mechanic, so I took it to the mechanic, he seemed to think the front derailleur was fine, but was still finding it difficult to get a smooth change he probably also thought I was being ridiculous when I was saying it was coming off, (probably thinking I'm changing gears wrong) he may be right about me changing gears wrong, but before, I could change gears wrong perfectly fine, so there is something wrong lol.

He also told me when I was there which was something I didn't realise, which was my chain is worn, and I would need to change my rear cassette, he used some sort of tool on my chain and wiggled it, it made a sort of clicking noise, and said the rear cassette would need to be changed when I change the chain. Is this right? for £50

If someone can somehow figure out my blabber I am in a bit of a pickle to say the least, and would really appreciate some good honest expertise ,

thanks,

Luke

richiebones

sooo...does the FD now work?

how many miles has the chain done? if its really streached and done lots of miles then its reasonable to say that both chain and cassette need replacing

lukebennett

it works if I am in about the 4th gear in the rear cassette but if I go higher it drops into the pedals.

I think that I probably do on average about 60 miles a week sometimes a lot more, so about 1,680 miles?

richiebones

sorry but it sounds like a FD set up issue to me
is this how you have set the stops....?
disconnect the FD cable, let the chain drop into the small ring at the front
shift into to largest cog at the back
put your thumb onto the FD body and turn the screw nearest to the frame
if the body of the derailleur moves thats the screw want...if it dosent its the other one.
screw it until their is a 1mmish gap between the inner plate of the body and the chain...
attach the cable
shift into the big chainring at the front and the smallest at the rear
grab the cable at the down tube (dont use the shifter)
pull the cable down whilst screwing down the other stop screw until their is a 1-2mm gap between the outer plate and the chain
set up like this you shouldnt be dropping the chain........

theadam4

FD's can be a pain sometimes! I would also recommend you check the cable. if it is old and dirty / rusty then that could hinder the shifting, it would also cause inconsistent shifts (which is what it sounds like you are getting) a new cable is only a couple of quid and easy to fix and rule out.

on the FD, I have had one in the past that needed to be slightly angled with the tail slightly in, otherwise it wouldn't shift smooth.. try that.

finally about the chain and cassette. If the chain is worn more than 1% then yes you will need a new cassette, if it is less you may be able to get away with just a new chain. There is a way to measure the chain stretch with out a checker, this website shows you how near the bottom of the page. http://sheldonbrown.com/chains.html

Good luck!!

lukebennett

thanks guys, I will try both of those, also do you think it is worth me trying to change the rear cassette and chain and that if it needs it, or just take it to the mechanic for £50 because he knows what he is doing?

drlodge

My Super Record FD will dump on the chain on the inside if I'm not careful - its properly setup and a top end piece of equipment. I just have to be gentle on the thumb shift and not press it fully home when shifting (3 clicks not 4). "Cheaper" shifters don't have this multi-click shift facility - you either change completely, or you don't.