Tuning gears......driving me mad!!!

Col1253

I am coming towards the end of my first ever bike build and am trying to fit new cables and tune (for want of a better phrase) the gears.

I have at last got the rear ones sorted but I can’t seem to get the front ones right no matter what I do!!

The main issue I am having is that no matter how much I tweak the front derailleur the chain keeps coming off when I change the gears, normally when I change down gear to the smaller cog. Now I know this sounds like the derailleur is simply in the wrong place but if I try and tweak it the other way, the chain falls off the other side which I have never seen before!! I have tried adjusting the actual height of the front derailleur but that does not seem to work either.

I am using a Shimano Ultegra derailleur and crank set and have a Shimano Hollowtech II bottom bracket.

I am basically trying to learn as I go along with this build and so far, no major disasters. I appreciate that there could be many reasons why I am failing at this task but..........Anyone out there have any ideas what I could be doing wrong?!?!?!

desweller

Sounds like you simply do not have the bottom limit screw wound in far enough.

arlowood

Take a look at this video

http://www.youtube.com/watch?v=lxV_vKlgolc

Step through the process as they descride (I know the accent is a bit irritating) and that should hopefully sort out your problems.

Remember - you need to detach the able before trying to set your low limit clearance

Col1253

Thanks guys, fingers crossed I think I have sorted it!!

Phil_D

What was the source of your problems in the end?

Pross

Rather than starting a new thread I'm going to hijack this one as the OP seems to have his issue sorted!

On the subject of tuning gears I'm have issues with my rear mech (105 with Tiagra levers). I am finding that I cannot get the adjustment set so that it goes both up and down the cassette seamlessly. If I adjust so that it goes up smoothly it won't come back down and vice versa and where you would expect it to be just right it does neither smoothly (the lever needs to be held over for a while to go up the cassette and it can take several seconds to finally drop back down, often changing at just the wrong moment under load).

Any idea how to overcome this? The only thing I can think of is that the cable itself has stretched and that I need to manual tighten the cable before fine tuning the gears but will this overcome the problem in both directions?

styxd

Pross wrote:

Rather than starting a new thread I'm going to hijack this one as the OP seems to have his issue sorted!

On the subject of tuning gears I'm have issues with my rear mech (105 with Tiagra levers). I am finding that I cannot get the adjustment set so that it goes both up and down the cassette seamlessly. If I adjust so that it goes up smoothly it won't come back down and vice versa and where you would expect it to be just right it does neither smoothly (the lever needs to be held over for a while to go up the cassette and it can take several seconds to finally drop back down, often changing at just the wrong moment under load).

Any idea how to overcome this? The only thing I can think of is that the cable itself has stretched and that I need to manual tighten the cable before fine tuning the gears but will this overcome the problem in both directions?

Could be sticky cables, outer cables to short or a bent mech hanger. These seem to be the 3 main things people overlook when having gear issues.

Col1253

Phil D......Can’t say for sure what the problem was in the end if I’m honest!! I watched the video on the link provided by arlowood (cheers for that by the way) and basically started again. After a few tweaks here and there it now seems to be ok although I have yet to actually go out for a proper ride on it as once I took it up and down the street to test it.....I discovered some play in my forks which in turn identified I needed a new headset!!!

Pross.....I would love to offer some useful insight into your problem but I am a total novice at bike maintenance hence my plea for help on here!! Hope you get it sorted though, gears have become the biggest pain in the bike build to date!!

arlowood

Pross wrote:

Rather than starting a new thread I'm going to hijack this one as the OP seems to have his issue sorted!

On the subject of tuning gears I'm have issues with my rear mech (105 with Tiagra levers). I am finding that I cannot get the adjustment set so that it goes both up and down the cassette seamlessly. If I adjust so that it goes up smoothly it won't come back down and vice versa and where you would expect it to be just right it does neither smoothly (the lever needs to be held over for a while to go up the cassette and it can take several seconds to finally drop back down, often changing at just the wrong moment under load).

Any idea how to overcome this? The only thing I can think of is that the cable itself has stretched and that I need to manual tighten the cable before fine tuning the gears but will this overcome the problem in both directions?

Hi there

Your problem suggests that the inner cable is not moving smoothly either due to some problems with the outer or fraying of the inner at some point.

As a suggestion - try going back to first principles as demonstrated in this video.

http://www.youtube.com/watch?feature=en ... JxVbo&NR=1

If your problems persist then it looks like inner or outer cable replacement is needed.