Crank Advice

im getting a new crankset shud i get 165mm or 170mm
?

What will fit you?

165 less chance of pedal strike especially if bottom bracket is not high. If you are taking the current advice not to lean, then it wouldn't really matter.

is there realy much of a differance ?cause im not sure wat to get

It depends on what sort of frame you are putting them on. If it is a conversion then the bottom bracket is probably closer to the ground than on a track frame so as you are going round corners at speed, and god forbid leaning, then your pedals may strike the ground with a longer crank. If you have a tighter geometry track frame the bottom bracket will be higher so this is less likely to happen but you may get toe strike at lower speeds. Which is when your toe or toe clip hits the front wheel. 5mm can make quite a difference.

There's 5mm of difference.

Damn! I knew there was an easier way of saying it.

http://www.gearcrave.com/wp-content/uploads/2008/05/mission-bicycles_05092008_msp.jpg one on of these frames wat would be good to use?

Depends what colour you got. I'd go with 170 for Gorgeous Baby Blue, 165 for anything else.

I can't really give you an answer based on those photos, plus I'm not an expert. I think either would be ok on those frames as the front wheel is not that tight and the bb looks a reasonable height. If you are worried about it get in touch with the bike whisperer and get a personal fit.

Blatant alias.

Alex - A modern external bearing crank (hollowtech II) will give better performance than any old square taper cranks. They are far stiffer and lighter due to the bigger diameter, thinner walled axle. Splined systems are ok (octalink) but suffer from reduced bearing life due to the larger axle with the bearing still inside the BB shell. Also splined systems may be harder to get parts for in the future as they were not around for very long (compared to square taper).

I don't know what chainline you get with a hollowtech II crank running on a single chainring but Clodge managed fine (until his axle snapped! but this is very rare).

I reckon a new pair of 105 HTII cranks will give better performance than an old square taper Dura Ace, and you can probably get them far cheaper. SRAM and Bontrager both make external bearing track specific cranks allready, I'm sure Shimano will follow soon.

i think sram do a singlespeed crankset which is hollowtech. seems pretty nice, £60/70 i think.

I think crane put one on his ti build. I'd like to know how they fare actually...