Does 2.5mm make a difference?

[slow down]

I'm thinking about switching my best bike to a compact, but I have a grey Centaur groupset and the only grey Centaur compact chainset I can find has 175mm cranks, where I normally ride 172.5mm. Does the 2.5mm really make any difference, or will I not notice?
Or does anyone know where I could get a 172.5mm grey Centaur compact chainset from?

 

[Yorkshireman]

I've had the same thing on some of the bikes I've had in the past and I never noticed the difference (if that helps), though I could have adjusted the seat post and forgotten.

 

[Fab Foodie]

Depends...
I'm happy on 170 or 172.5 (apparently optimal length for me), but could not get-on at all with the 175's I had on my previous steed, was just 2.5mm too far.

 

[Steve Austin]

It can depend on how tall you are, allegedly.

i've ridden 170 through to 180 and all have been fine. i did find spinning a 170 a tad tiring though.
IIRC there is some site that has loads of measurements to see if certain size cranks will be ok for leg length.

 

[slow down]

Cheers - I may give it a try. I can get the 175 chainset for £40 (just need to remember where I saw it ) so not that much of a gamble I guess.

 

[Elmer Fudd]

Here may help, or Here

 

[slow down]

Here may help, or Here

Mmmm - one recommends 170mm cranks, the other 181mm!

 

[Elmer Fudd]

Mmmm - one recommends 170mm cranks, the other 181mm!

Thats the thing though, I'm told for my inside leg I need 165mm, currently using 170mm but wishing I had 175mm !