Triple or Double crankset???

AskyourmA

I have a Lapierre Audacio 400 (2010). Its got a full Shimano Tiagra groupset with a triple crank and a 9 speed cassette. I'm looking to upgrade with nearly new parts from ebay and other related sites for as little as possible (funds are low). Can I get away with changing to a Shimano Ultegra or 105 double crankset, front & rear derailleur and 10 speed cassette and use exsisting tiagra shifters???

kenmc

the shifters will be your problem here, with 9speed shifter you will only be able to access 9 of your 10 rear gears. the front one will also be weird, as you've got a triple driving a double crankset.

07Lapierre

If you stick with 9 speed cassette, your right shifter will work. Once you change the front Chainset to a double, you should be able to adjust the limit screws on the front derailleur to stop it shifting to the "granny" gear (which you won't have if you change to a double chainset)

Explosive_Cornflake

Stick with 9 speed, but get an old [new] Ultergra 9 s-peed casette.
Use whatever frotn cranks you want. As mentioned above, you can use your triple shifter on a double, but I wouldn't use a 9 speed shifter on a 10 speed block.
Something like at 9 speed 12-25 or a 11-23 on double would be fine.

AskyourmA

Thanks for the info lads... I have sourced a 105 crankset (new) with bb for $70 in SF USA, so I have my bro on the case who can check it out and get it home for me... Its on craigslist, as follows;
Brand new Shimano 105 Hollowtech Octalink 170mm Crank 53/39.
Innovative superlight crank with hollow arms and hollowed out spider.
This crank is the same as the Ultegra except the chainrings have a slightly different shape.
Orig. MSRP $180; Sell $35
105 Octalink English Hollowtech spindle bottom bracket. 68x109.5, brand new never used.
Orig. MSRP $70; Sell $35

Not sure if the BB will suit my Lapierre, and the Tiagra cranks I have are 175mm, so any thoughts on the above would be appreciated... For the record my Lapierre is a 55cm Frame and I would be a 33inch leg in jeans etc...

ashleey

Octalink is not new! Don't buy. You need to look for Hollowtech II type shimano stuff. Newest 105 is 5700. Your current bike probably has external cups as a bottom bracket

dave_o_brien

Not meaning to derail your plans, but why are you looking to do this? If you want to upgrade your bike, going to a double makes acertain amount of sense, but going from a Hollowtech 2 to an Octalink does not. Also, the upgrade in changing mechs is small compared to the outlay, unless you change your shifters, which is expensive. Wheels would be where I would spend my money on your bike.

AskyourmA

Thanks Lads, Hollowtech II it is so... As I said I'm looking to upgrade for the summer for small money and then next year it's new bike...

ashleey

New shifters cost as much as a good set of wheels. Tiagra 9 speed is a good set up and if you want to change things here just buy new chain rings and cassette and chain of a higher spec when yours wear out. Buy some mavic ksyrium wheels and continental gp tyres with your cash. Alternatively buy a new tiagra double chainset from ribble and a double front mech and leave everything else alone

AskyourmA

@ashleey I here you man and I'm checking out your rec's... On ribble all I can find is a Tiagra 10 speed double crankset but I have found this on another site...

http://www.shinybikes.com/shimano-tiagra-9-speed-double-chainset.html

Are these the wheels you would recommend...

http://www.ribblecycles.co.uk/sp/road-track-bike/Mavic-WHEELS-FACTORY-ROAD-TRI-Mavic-Ksyrium-Equipe-Clincher-Wheels-Pair/MAVIWHFR480

If so I need to start saving...

ashleey

That tiagra 4500 double is the correct replacement and you will need a new front dérailleur for a double. The new tiagra 4600 is 10 speed. The 4600 crankset should still work with 9 speed chains and rear but you may need spacers to make the two chain rings slightly wider apart but maybe not.
To be honest you could get shimano rs20 wheels for less than the mavics and will be a good wheel with your bike.