Tiagra v 105 Groupset/Ultegra

npowell28

I've have a Bianchi with Tiagra front and rear mechs/cassette/shifters and an FSA vero 34/50 chainset. I've noticed that there is some wear on the chain rings. There are a couple of chipped teeth. The cassette is fine.

1. The bloke at my lbs said that i can't change just one part of the drive train and that i must change it all. Is that true?

2. If i have to change it all should i just replace it with tiagra bits or should i go 105 or even ultegra. I only have the one road bike so use it all year round for work and play.

Thanks for your help.

nochekmate

I suggest that if the advice from the guy at your lbs is genuine, then I'd look for another lbs - he doesn't know what he is talking about and looks like he's out to make money from you.

You can happily change out the chainset and not worry too much about front mech, rear mech, shifters etc.

When you say that some of the teeth on the chainset are worn are you sure that this is not by design. Chainsets don't always have uniform teeth and the profile of some teeth may be different to help with shifting processes.

npowell28

Thanks. What i meant to say was that he said i should change the entire drivetrain e.g. the cassette, chain and chainring as they should all wear down at the same rate?????

ddraver

^that is generally the advice yes....How long have you been using the kit?

u05harrisb

Id just go for full tiagra again, that is inless you have some free money or are racing or similar. if you dont feel disadvantaged with tiagra at the moment then i wouldnt bother really, but of coarse up to you ive got full sora on my bike, does the job well enough when racing and stuff but will upgrade to tiagra when it wears out

unixnerd

I'll bet you could happily run it for another 1000+ miles and never notice the difference. So it's a bit worn, if it all has to replaced anyway just keeping running it until you start to have shifting problems.

lemoncurd

Agree with unixnerd here, if it works then run it until it's knackered (unless you want to upgrade for aesthetic reasons).

Also bear in mind that some of the teeth on chainrings have different profiles to help shifting, these can appear to be damaged. Look closely at this image and you'll see that there are teeth near the top that are slightly different shapes to the others.

http://s.wiggle.co.uk/images/shimano-4603-cset-zoom.jpg

pbt150

Chainrings aren't symmetrical all the way round, some teeth are shorter than others to help shifting.

Chainrings also wear much more slowly than cassettes because you shift less and engage more teeth at a time. If you need to replace them though just buy new 9 speed rings.

It's not really worth switching to 105 or Ultegra. The shifters will need changing, and they cost £££!