herneweb

as everyone rides with either a 170-175 crank then consider yourself lucky to have long legs since these will enable you to spin much faster easier, as it is a much shorter lever relatively.
you want more torque for climbing?; put it up another gear.
you need to turn 85rpm climbing and 120 for the rest of the day.
ride with 190 and I think you'd fall off!

Richy
By  Anonymous
 

Thanks Richy. I recently did a test and realised my cadence is much lower than I thought so perhaps I will concentrate on getting the revs up for the moment.
By  iain
 

after heated debate around the drinking table we agreed that 180cranks maybe suitable for you
as these exist, however, its worthwhile to consider the additional flexibility/structural integrity of the crank and perhaps as a consequence quite a heavier crank set.

my opinion is 175 is a great all-round compromise...

Richy
By  Anonymous
 

Richy, nothing like an evening round the table discussing cranks ;-).

But seriously, thanks for the advice, I will stick to the 175s for the moment and try-out the 180s if I get the opportunity.

Iain
By  iain
 

For what it's worth, I'm also 6'3'', and I tried 170, 172.5 and 175 over the past two years. I settled on 175mm, it just feels way more natural for long legs, I'd never go back to shorter one now. As for cadence, even an hour a week on rollers will do wonders - I moved my cadence up from a natrual 75 to around 90 in the last six months.
By  Richard
 

Also 6'3" with an inseam of 91cm to 92cm and a bit inseam [cleated shoes of and on]. Had 175 cranks fitted as standard to my Bianchi. Eventually found some 180cm Truvativ Rolleurs at a good price <£100 incl BB cups. Did not notice much increase in power as some would suggest from longer cranks, but did notice contrary to popular belief that I was able to maintain a higher cadence. Which may suggest that 175cm cranks were far too short for my long legs. Would like to try some 185 or 190s as i am now convinced that 180 should be the absolute minimum but the expense prohibits this as they would have to be custom made. I have noticed that there are a few 2005/6 alloy record cranksets available in 180cm lengths at £70-£80.

PS

I NO LONGER HAVE ANY KNEE PAINS SINCE MOVING TO A LONGER 180 CRANK
By  kevinp
 

Thanks for the addition kevinp, good to hear more on this from other tall riders, I'll add the post to the permanent list under articles.
By  iain
 

I have been experimenting with longer cranks for a two years now. being 6 foot 5 longer to my mind was better but there are costs. Initially I went for 185's then 205's and the initial feel was weird. As I got used to them they seemed to give more power on climbs etc. but they were too long on the corning in races. I then switched to 195's and they seemed to be a lot better. Although I won a couple of races with these I wonder about the increased amount of flexing the knee had to do and the cadence. Being an automotive engineer having worked in engine design the longer crank throws in an engine always limited our top end speed. A shorter stroke always gave more power and higher revs. If you translate this argument to a bicycle crank your choice of crank length should not just be down to inside leg measurement but also optimal cadence. I find sometimes with the longer cranks there can be a tendency for you to ?hop? in the saddle as your leg goes through the extremes of flex. My gut feeling is that a 190mm crank would be ideal for me and that the 195 s are too long.
By  aonghus
 

Please tell me where you got 205mm cranks, who makes them?
By  toolman1900@yahoo.com