changing cassette/shifter??

[albion]

Methinks they are identical but in this case the Deore item is the higher quality.

 

[Kestevan]

Doh,

6 and 9 they look the same.......ish.

I've got a 9 spd Ultegra on mine at the moment,
http://www.chainreactioncycles.com/Models.aspx?ModelID=1094
but it was on special offer, I didn't pay £40.00

TBH it's maybe a few grams lighter than the tiagra, which will be about the same as the Deore.
If the weight is that important to you, put less water in your bidon

With regards to the 105 10spd stuff, you'll find that your tiagra shifters only handle 9 speeds. Changing to a 10spd setup gets expensive quickly.

I'd stick with the Tiagra if you can source one, or try and find a cheap Ultegra 9 spd.

 

[xxmimixx]

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