Crank Length= inseam(mm) * 0.192 for merckx

[Tmogul]

I found this site about crank length http://www.cranklength.info/cranks.htm and it has a list of the crank length to leg relationship of some of the legends in cycling. It seems Eddy himself used very short cranks relative to his leg length. Using his formula puts me (inseam 795mm) at a very short length. Anyone here ever try shorter cranks? If I follow Hinault or Anquetil's formula then I'm at 165 cranks. Curious as to your experiences. Any track riders here who jump between crank lengths with road riding?

[flydhest]

I jump among three lengths. 170 on the track bike (though ridden on the road) 175 on the 'cross bike and steel road bike, 180 on the Ti road bike.

YMMV, but as long as I adjust the position to what feels right, I don't have problems.

[Tmogul]

Was wondering your reason for choosing so many different lengths. Do you feel a better spin with the shorter ones or is it harder to climb steep hills with them? Any preferences? Thanks

[flydhest]

Was wondering your reason for choosing so many different lengths. Do you feel a better spin with the shorter ones or is it harder to climb steep hills with them? Any preferences? Thanks

(hanging head) for no really good reason. Here's how it happened. I got a road bike, spec'd it with 175 because that seems logical, it's what I was riding before, and is what just about anybody would have put me on. Got my fixie, and wanted to put Campy Pista cranks on it because I think they are pretty cool. They only go to 170. I made up some lie to myself about that being fine and that I'll be able to spin better/easier. In reality, I have spun my 175 on rollers at over 150, so spinning isn't much or a limiting factor. . . . let's just move on so that my superficiality isn't obvious.

I got the wife TA cranks for her road bike. They look cool and come in lots of lengths and offer a wide range in choice for chainrings. I should get a set, I says to myself. Why not experiment to see what 180s do, espcially for your seated climbing. As it turns out, I notice the difference (I think) when I'm cruising in the 25mph range on the flats. I feel like I can settle into a groove just a bit better. Not much, mind you, but a bit.

I put the old 175 cranks on my 'cross bike.

Last November/December I snagged a NOS steel frame/fork that I have been wanting for a while. Decided to build it up with Campy Centaur and they only go to 175. I'm not convinced that 180 is perfect for me and I have to be a bit more mindful of positioning to make sure I don't stress my knees with the longer cranks, so 175 seemed like a good idea.

Final result is that I can notice a slight difference with the 180s versus the 175s. I don't notice a huge adjustment period when switching, maybe the first 15 minutes. For the fixed gear, I'm riding it so differently than everything else it's harder to compare, but the times when I'm just riding somewhat fast, I notice that the cranks are shorter. I'm spinning faster, however, because the gearing is set up to go up and down hill, so if I'm cruising above 20, I'm spinning pretty fast. That really complicates the inference problem for me.

As I said, your mileage may vary, and my body is reasonably adaptable.

[Tmogul]

Well you have done what I was thinking about doing and well according to your experiement it seems one should just sick to the stock stuff. I use 175 on mtn and 172.5 on road and 175 on tandem. I had no choice in the matter its just what the bikes came with. And I think most purchasers of high end stuff have very specific aesthetic tastes and while one person may call it superficiality another would say personal preference. :) :cool: I to was justifying possible changes with the ideas that one could spin easier and have decreased knee angle at top of stroke leading to less knee strain and more leverage .............etc. Any others out there? I also thought about just going 175 and keep all my bikes the same.

[William]

I found that when I switched to 180's that I could stay on top of the gear and apply a little more power when climbing. I'm a seated climber and just power away. I felt like I was mashing a little more on the 175's to stay on top. 180's just seemed easier. I could probably go to an even longer set but at this point I'm just considering it.

Lennard Zinn has some interesting thoughts on crank length, though generally geared more toward larger riders. You can read the articles on his web site, or go to the barbarianbikeblog where I'm collecting info for larger stronger riders.

William

[flydhest]

BigBill,

What you say makes sense to me, I think, once we factor in that you're bigger than me. I think if I try to compare my 170s to my 175s, I'd likely have a similar view, but it's a bit muddied, given the above discussion.

[vaxn8r]

According to the formula I should be on 165's. I actually tried that for a couple of years in the early 90's. I never felt I could generate much power. Even after a couple of years it never felt good. I'm much better with the ubiquitous 172.5's.