Difference in front and rear mech's performance

shdaxner

Hi All

So as the title says really, I am currently using a 2008 Carrera Vanquish which has a Tiagra rear mech and a Sora front, the Tiagra rear i find has a nice gear change and is easy to set up, whereas the Sora front is a nightmare to set up and not the best of changes
Because of this i was thinking of upgrading the Sora front to either an Ultegra or 105 front and if it is worth it, doing the same with the rear mech.
But i am a little stuck, as before i exchange my monies i want a little bit of reassurance as to how much an improvement it will be (if any)

Any one have any clues?

ugo.santalucia

shdaxner wrote:

Hi All

So as the title says really, I am currently using a 2008 Carrera Vanquish which has a Tiagra rear mech and a Sora front, the Tiagra rear i find has a nice gear change and is easy to set up, whereas the Sora front is a nightmare to set up and not the best of changes
Because of this i was thinking of upgrading the Sora front to either an Ultegra or 105 front and if it is worth it, doing the same with the rear mech.
But i am a little stuck, as before i exchange my monies i want a little bit of reassurance as to how much an improvement it will be (if any)

Any one have any clues?

Are you sure you are setting it properly, with the correct tension? Front Mechs are all the same and you might end up spending money and having the same problem. Front indexed shifting is a stupid invention and it rarely works flawlessly... a ratchet would give you a lot less hassle... what I am trying to say is that probably the problem is in the levers rather than the mech. You need to set the right tension

shdaxner

Hmm, Thanks for the reply, i dont understand what you mean by ' the correct tension ' i must add im a relative newbie to bikes but i do all my own maintenance but indexing at the moment is proving to be a real PITA, it seems to take a few days from stripping down to have the bike running nicely again. Although this is the first road bike i have ever owned so have never fiddled with the levers (Tiagra Shifters by the way)

I was thinking of booking it in to get indexed at my LBS but i would much prefer to learn how to index myself, at the moment it is running nicely, nice and quite and good changes but everytime i strip it down and give it a clean it takes days of tweaking to be nice again.

Also, are we sure that the higher end mechs are no different? ive read alot of reviews and information about the higher end parts people seem to think there is a considerable difference.

Thanks Again

ugo.santalucia

shdaxner wrote:

Hmm, Thanks for the reply, i dont understand what you mean by ' the correct tension ' i must add im a relative newbie to bikes but i do all my own maintenance but indexing at the moment is proving to be a real PITA, it seems to take a few days from stripping down to have the bike running nicely again. Although this is the first road bike i have ever owned so have never fiddled with the levers (Tiagra Shifters by the way)

I was thinking of booking it in to get indexed at my LBS but i would much prefer to learn how to index myself, at the moment it is running nicely, nice and quite and good changes but everytime i strip it down and give it a clean it takes days of tweaking to be nice again.

Also, are we sure that the higher end mechs are no different? ive read alot of reviews and information about the higher end parts people seem to think there is a considerable difference.

Thanks Again

If you want to believe that...
Take a Dura Ace front derailleur, then take the Sora... the engineering is the same, a clamped cable pulls an arm which moves the derailleur, then a spring pushes it back when you release the tension. Indexing has nothing to do with the derailleur. It's all in getting the right tension at the cable. I suggest you shift to the small ring, all the way down and check the tension in the cable. If it is slack, give it some tension, if it is too tense, release it a bit. That's all there is to it, whether it's Sora or Dura Ace, it's the same. The limiting screws are only to be adjusted in case of overshifting (chain off the rings) or undershifting (chain doesn't go on the ring regardless of the tension).

Monty Dog

IME 99% of front mech problems are due to incorrect alignment / positioning. Suggest you look at www.parktool.com for detailed instructions. Adjusting the cable tension is fine-tuning.