Shifter questions

jteighty

Hi,

I have a 2009 Boardman road comp and I need to replace my left shifter (tiagra triple). I don't quite know how gear mechanisms work, so please can you help me out with my ignorance. I was told I can either replace my shifter with the same model, or upgrade both shifters. I was looking into upgrading them but I'm unsure how the whole mechanism works. I know my bike has tiagra 9 speeds but uses a 105 derailer which is 10 speed. Can i just change the shifters to any 105s or ultegras and it'll work or do they need to be 9 speed. I don't really know the different components of the gears and which part are dependent on others.

Please advise.

Many thanks,

JT80

nicklouse

they need to match the cassette. if you want to go for a 10spd you will need to change the cassette and the chain.

andy_wrx

i.e. either replace with other 9sp Shimano shifters like Tiagra or Sora and keep your 9sp cassette and chain

Or replace with 10sp Shimano shifters like 105 or Ultegra or Dura Ace, but you'll need matching 10sp cassette and chain

The front & rear derailleurs, chainset and brakes will work with 10sp or 9sp quite happily

jteighty

Thanks for the responses. When you say a new cassette do you mean another ring or a full set of rings? If 9spd=9 rings, can I add a smaller ring to make it 10speed? Also what sort of chain will I need? It seems a lot simpler to just get a replacement as I loved my tiagra shifters and then I won't need to mess around with anything.

Thanks,

JT80

andy_wrx

A full cassette, all 10 cogs. You can't just add another cog to a 9 to make a 10.

The issue is that the cogs are closer together on a 10sp cassette than on a 9sp one (the overall width of all 10 is same as the 9)
A 10sp shifter is designed to pull slightly less cable with every click than a 9sp shifter does, so with every cick a 10sp shifter will tell the rear derailleur how far it has to move based on how far apart the cogs on a 10sp cassette are, and a 9sp shifter will tell the rear derailleur how far it has to move based on how far apart the 9sp cogs are.
Thus you need to match the cassette with the shifters (i.e. both 9sp, or both 10sp)

Similarly a 10sp chain is a little narrower than a 9sp chain, so as to fit the slightly slightly closer-together cogs of the cassette.



Simplest and cheapest, as you say, might be to look out for a lefthand Tiagra shifter to replace-with-same your broken one : sometimes shops split a pair when someone has broken one like you, or you can see them on eBay
- e.g. this one http://www.ebay.co.uk/itm/Tiagra-Left-H ... 336aa1514e


And actually, as it's your lefthand one which has broken, you have another choice - you can leave the righthand one alone (running the 9sp rear cassette), and just change the broken lefthand one which runs the front chainrings
The front is the same whether it's 8sp, 9sp or 10sp, so any Shimano lefthand triple shifter would work - Tiagra, 105, Ultegra, etc.
What you'd have to do here is ensure it can work a triple, not just a 2-ring double or compact
- problem is it wouldn't match : but only an issue if you are bothered by cosmetic things ?


Without meaning to insult, but from the questions you're asking I'd suggest you'll need to get a shop to fit it for you though, as whilst it's not hugely complicated or needs specialist tools, you do need to know what you're doing

McBain_v1

Read Sheldon Brown's]/b] website which is excellent - he will be sorely missed.

jteighty

andy_wrx wrote:

A full cassette, all 10 cogs. You can't just add another cog to a 9 to make a 10.

The issue is that the cogs are closer together on a 10sp cassette than on a 9sp one (the overall width of all 10 is same as the 9)
A 10sp shifter is designed to pull slightly less cable with every click than a 9sp shifter does, so with every cick a 10sp shifter will tell the rear derailleur how far it has to move based on how far apart the cogs on a 10sp cassette are, and a 9sp shifter will tell the rear derailleur how far it has to move based on how far apart the 9sp cogs are.
Thus you need to match the cassette with the shifters (i.e. both 9sp, or both 10sp)

Similarly a 10sp chain is a little narrower than a 9sp chain, so as to fit the slightly slightly closer-together cogs of the cassette.



Simplest and cheapest, as you say, might be to look out for a lefthand Tiagra shifter to replace-with-same your broken one : sometimes shops split a pair when someone has broken one like you, or you can see them on eBay
- e.g. this one http://www.ebay.co.uk/itm/Tiagra-Left-H ... 336aa1514e


And actually, as it's your lefthand one which has broken, you have another choice - you can leave the righthand one alone (running the 9sp rear cassette), and just change the broken lefthand one which runs the front chainrings
The front is the same whether it's 8sp, 9sp or 10sp, so any Shimano lefthand triple shifter would work - Tiagra, 105, Ultegra, etc.
What you'd have to do here is ensure it can work a triple, not just a 2-ring double or compact
- problem is it wouldn't match : but only an issue if you are bothered by cosmetic things ?


Without meaning to insult, but from the questions you're asking I'd suggest you'll need to get a shop to fit it for you though, as whilst it's not hugely complicated or needs specialist tools, you do need to know what you're doing

Wow, thanks for the detailed response. I really appreciate it.. I think I'll just buy a single tiagra from CRC and get a shop to fit it as you say.

Many thanks

k-dog

I think that's the right decision.

Upgrading to 10 speed would be nice - but you'd need a pair of (more expensive) shifters, a cassette and a chain.

That's about £200 of stuff - and as you've seen you can get the LH shifter for £85 on CRC.