Changing front crankset from standard to compact

garrynolan

Hi, really need lower gear for hills so... what do I need to change over? Currently running full Shimano 105 10 speed gears approx. 5 years old (new rear cassette and chain). Any idea of cost? Also, a question showing my ignorance - how do you find the pedal/crank length? Thanks very much in advance. G.

gozzy

All you need is a compact crankset, if you manage to get the same series cranks then you won't even need to switch the NDS crank.
You'll probably need to shorten your chain a little if your standard double has more than 50t big ring.
Crank length and model is stamped on the inside of each crank, by the pedal thread.
You can find the price by googling the model number, or looking on CRC/Merlin/Wiggle/eBay etc.

StillGoing

And drop the FD slightly.

garrynolan

Brilliant - thanks very much Gozzy. Also - philthy3. What is the FD? Ta. G.

Terrytibbs

garrynolan wrote:

Brilliant - thanks very much Gozzy. Also - philthy3. What is the FD? Ta. G.

Front dérailleur. So, you'd drop it until it's 1-3mm away from the outer ring for the best set up.

Other options you could do; I presume you have a cassette with around a 25/26 largest sprocket if you have a double chainset. The cheapest option would be to change the cassette to a maximum large sprocket of 30t (presuming you have an SS rear mech, 30t is the max recommended). And likely a new chain. 105 cassette and 10sp chain, you could get for about £45-50 maybe a bit less. You could get a 11-28 cassette on a 39/53 without changing chain...probably..just, but I'd just change the chain for what it's worth.

If you wanted an even lower gear you could get an 11-32t cassette, a GS 105 rear mech and a chain. That'd set you back maybe around £80ish.

With those two options, you have the ability to get up most hills but also keep the fast gears for when you need them. And if you wanted it even cheaper, go for Tiagra.

garrynolan

That's very helpful. Thanks again. G.