Now I am over 6 foot, have always used 175mm cranks in the past, will running 170mm be ok, or is it s big no no?

XC/Trail riding, on a hardtail if that helps.

I will obviously notice, but in a bad way, good way?

Any tall people running shorter cranks on anything other than a DH bike?

AGAIN ??? Sweet Jesus 🙁

Apologies SFB for ruining your day, really sorry, what must I have been thinking.

Forgot about the search, used it now, will go and read.

Again a thousand apologies, can you ever forgive me?

(Perhaps a link to the search i missed would have been more constructive?, just a thought)

Perhaps a link to the search i missed would have been more constructive?

it comes up every 2 weeks forever…
and people will tell you it makes such a huge difference your legs will fall off or no difference at all

Go clicky here -> Crank Arm Length Calculation Thingy

Have read the thread from the other day, seems most people assume i’ll not notice..

Will give it a go.

Go read the thread for the day before that though and it’ll tell you that you will notice and you’ll damage your knees and maybe even die. Best bet I reckon is to get some very cheap cranks in a different lengths and see which you prefer. The different length can take a bit of getting used to.
I certainly notice different crank lengths, but which is actually better is another question….

there is a very good chapter in Mike Burrows “Bicycle Design” book on crank length.

You’ll def notice, I did when I changed although I am *ahem* just under 6 foot….

I use 170 on the road
170 on the track

Makes sense to use em on the MTB – Stopped me knees urtin….

went through this myself the other year, wanted new crankset and the best deal by far was 170 arms. i’m 5ft11 and by default (as in ‘came on the bikes’) had always used 175 and 172.5 on the road.

after a lot of googling came to the assumption that i would’nt notice much difference.

i was wrong, in fact i hated them as they spinned up way too fast for me. found out i’m definitely a slow but sure grinder, all my bikes now 175.