Shimano 105 standard to compact.

garrynolan

Hi all, I run Shimano 105 standard and want change to a compact (50/34) set-up. Can someone give me advice on how to do this? Please bear in mind that it needs to be: a/ cheap, and b/ easy. Thanks very much. G.

gozzy

Buy and fit a compact 105, or another compatible, chainset. That ought to do the trick.

Beeker

I recently did the same switch. Front derailleur needed slight adjustment and chain needed to be shortened....hills are a little easier now!

Rodders30

Gozzy wrote:

Buy and fit a compact 105, or another compatible, chainset. That ought to do the trick.

Excellent, I couldnt help but laugh

buckmulligan

Yeah it depends what chainset you've got, but it should just be a straight swap. I'd guess it's a hollowtech one, in which case all you'll need is the star-shaped tool to get the right crank arm cap off and a 5mm allen key to undo the pinch bolts and away you go! Not even sure you'll need to adjust the front derailleur, is the chainring spacing different between a std and a compact? Even if you do, it's only a 10 minute job all in.

I'm thinking about going the other way, so I'd be happy to swap my Tiagra compact for your 105 standard!

garrynolan

Thanks for all the replies - some useful info in there. G.

haf1zur

How can I tell if mine is Compact or Standard? Count the tooths?

k-dog

You could count the teeth - it often says on them too.

If changing you'll probably have to lower the front mech too which will change the cable tension and mean that you'll have to adjust it to get it to shift properly.

haf1zur

so guessing 53-39 is standard?

k-dog

That's right.

houndlegs

Go to the shimano tech docs website and follow the fitting advice on there,it's really straightforward.
And I should know cos I ain't long done it myself