Bike set up. Please help!!!!

[jpb]

hi folks I have a question. I'm currently upgrading my Tiagra set up to ultegra 6700. I have changed the front & rear derailleurs and the chainset. I haven't yet changed the cassette chain or levers as I need to wait another month (keep the wife happy).

Whilst waiting a month, am I able to use this set up using the 9 speed chain/cassette and shifters. I asked a specialised shop and they said it is fine yet I went to a shop where they sell all trek gear and they say no. I'm desperate to get out on it but don't want to damage it if I can't ride it with this set up.

Your help is much needed and appreciated in this dilemma!!!

 

[jpb]

hi folks I have a question. I'm currently upgrading my Tiagra set up to ultegra 6700. I have changed the front & rear derailleurs and the chainset. I haven't yet changed the cassette chain or levers as I need to wait another month (keep the wife happy).

Whilst waiting a month, am I able to use this set up using the 9 speed chain/cassette and shifters. I asked a specialised shop and they said it is fine yet I went to a shop where they sell all trek gear and they say no. I'm desperate to get out on it but don't want to damage it if I can't ride it with this set up.

Your help is much needed and appreciated in this dilemma!!!

 

[Oldlegs]

You should be fine on that setup.

Did the trek shop say why it would'nt work. Possibly they thought you had changed the shifters as well?

 

[accountantpete]

I think you would be ok - the Tiagra chainrings are 9/10spd aren't they?

The problem is that the 6700 chainset is .5mm narrower between the rings and if you use the old chain it is going to scratch it.

Should be ok if you keep on the big ring though!

 

[fossyant]

Fine. Change levers chain and cassette when ready.

 

[aberal]

Personally I'd wait a month, hard as that might be. Old (thus worn) cassette and chain and shiny new (thus unworn) new chainrings and rear derailleur put together are probably bad ideas. I doubt that the front derailleur will make much difference to anything. Plus, apart from anything else - I would guarantee that now sooner have you got the new stuff up and running smoothly enough and you will have to go through the same setting up thing all over again one month later with the new shifters/cables etc. Best to do it all at once.

 

[jpb]

The Tiagra is 9 speed. The guy in the Trek shop said that it could damage the chainset but I don't see how. I can really wait a month as I'll have nothing to ride on. Not riding since Wednesday (last part came today) I killing me. I have just bought the 10 speed chain but got a kms instead of the 6700 because I've heard bad things about the new chain this year. Could I use the 10 speed chain on a nine speed cassette or would that not work because it's too narrow for the cassette?

 

[jpb]

** can't wait a month** (typo)!

 

[aberal]

You may have to upset the wife...

 

[jpb]

Ha. I don't think that's worth considering.

 

[jpb]

Or another idea would be to get the new cassette which I can do but not the shifters. Would this work? Everything would then be 10 speed and new apart from the 9 speed shifters. Wouldn't be able to buy the 6700 shifters this month as they're the most expensive @ £240 and there's no talking the wife into that this month after all I've spent so far!

 

[aberal]

There is a general piece of advice (or good practice) which states that you should change your chainrings and cassette every time you change your chain - because wear on a chain is uneven and uneven wear can then cause problems on existing chainrings etc etc. Now that's probably good advice (or good practice) - though hardly anyone does that. But it you accept the principle, and looking at the big changes you are talking about, if you can change the drive train in one go, then that would go some way to avoiding any potential problems. Ideally, you should have changed your drivetrain - cassette, chain, rear derailleur and chainrings first. Then shifters, cables and front derailleur second. IMHO.

 

[jpb]

Cool. I'm going to change everything first before I ride it apart from the shifters. I'm guessing the only downside of that is only being able to change to 9 gears instead of 10.

 

[Oldlegs]

No!

You cannot use 9 spd shifters on a 10 spd cassette.

Edit: To explain.

A 9 spd shifter pulls the derailleur nine equal movements across the cassette. A ten speed cassette has much narrower spacing and the shifter will try and put you in say gear 5 1/2 - this does not work.


Hope that makes sense - it's past my bedtime.


Beware donkeys bearing good news!

 

[jpb]

It does. Thanks for the info. I think the best thing to do is just wait until I get the shifters. As much as it kills me to wait...it's the best option