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Follow-up question on climbing set up.(16 posts)

Follow-up question on climbing set up.MXL02
Oct 21, 2002 8:31 PM
It sounded like a lot of climbers use 172.5 cranks...yet I've been told that an aft position of your saddle is important to get leverage during climbing. Can you get your saddle back far enough with the shorter cranks?
Are you on 175mm cranks?jtferraro
Oct 21, 2002 8:44 PM
I'm trying to figure out which to spec. my new bike with. It is a 58cm Trek(56cm c-t) and I have a 33" inseam(84/85cm).

Thanks,

-Jeff
Are you on 175mm cranks?outofthesaddle
Oct 22, 2002 8:02 AM
I live near a mountain (Mt. Diablo - 10.3 miles/3500 ft) and climb with 175 and 172.5 cranks both on 58cm Treks. I really don't notice any difference in "leverage" between the two set ups. I recently saw a write up by Leonard Zinn of a small study he did which pretty much concluded that crank length (within a reasonably broad range - I think it was 160mm-180mm) didn't impact power output much. Someone else may remember the article and have a link.
Are you on 175mm cranks?look271
Oct 23, 2002 7:29 AM
I read a similar article a few years ago. It seems to be more of a matter of personal preferance than anything. For me, going from 170 to 172.5 I felt a difference. Going from the 172.5's to the 175's really didn't feel much different at all. Performance? I still s$#k!
Yes and I ride a 56cm C-TMXL02
Oct 22, 2002 8:04 AM
My LBS told me I was borderline 172.5 vs 175. I don't do a lot of climbing and the hills I do encounter aren't very difficult. I don't know how much of a difference it actually makes. I ride a Colnago which has a rather short top tube and not much set back, so it is a little difficult to get my seat back far enough to recruit more of my posterior thigh musculature, which is especially important for climbing. Riding a 172.5 would make this even more difficult. FYI, my inseam is 32.75 inches, 83cms.
re: Follow-up question on climbing set up.Juanmoretime
Oct 22, 2002 1:56 AM
I can since I'm 6'1" riding a 59cc Litespeed Vortex with a 57.5 top tube. I do have a 35' inseam. I used to ride 175 when I was doing more time trialing but went to 172.5 2 years ago and really like spinning. I'm sure my knees will like me later too!
Did you really notice a differenceJL
Oct 22, 2002 6:16 AM
going down 2.5 mm? It doesn't seem like that big a difference.

Just wondering.

John
Can you tell the difference in climbing?McAndrus
Oct 22, 2002 6:44 AM
The ease of spinning with a shorter crank seems obvious. Can you tell any difference in climbing power between the 175s and 172.5s?
Can you tell the difference in climbing?Juanmoretime
Oct 22, 2002 8:38 AM
Going to shorter cranks can you tell a diference, not immediately. When I was on 175's I used to think 80 RPM was quite a bit. Plus with the longer lever, you tend to muscle it up. It took probably almost a year with the shorter cranks to learn to spin. I do think that I climb more effeciently on the shorter cranks and feel less fatigued after a climbs since I'm spinning it up verses having to use muscle strength. I think the change was worth it but if your looking for an immediate change, that won't happen. I now find most of my rides I stay mostly on the small chain ring and still average 19 to 20 MPH on a solo easy ride.
Can you tell the difference in climbing?yeah right
Oct 22, 2002 8:47 AM
if in reality you could attribute that much change to .0025 meters difference in length I'd be shocked.

We're talking about 1.4% difference in length

What you experienced was becoming a better cyclist.
Can you tell the difference in climbing?Juanmoretime
Oct 22, 2002 9:10 AM
I don't really think that is the case of me becoming a better cyclist. I've been cycling for over 30 years. Until four years ago, at the age of 41 at the time, I was still winning races, not age group, overall. The only reason I stopped winning is because that is also the year I stopped racing.
fair enoughyeah right
Oct 22, 2002 10:46 AM
I still doubt it's because the length difference
Don't forget...it's 2.5 on both cranks, equalling 5mm diff. (nm)jtferraro
Oct 22, 2002 11:42 AM
didn't take much math or physics, hunh?yeah right
Oct 22, 2002 2:47 PM
5mm out of 350mm still equals =.014 or 1.4% overall difference.

Just because there are two levers doesn't change the issue.
and you didn't take much English, "huh"? I'm not your hun! ;-)jtferraro
Oct 22, 2002 7:28 PM
I didn't bother doing the conversion, but just wanted to remind you to consider both cranks, in the event that you hadn't.

-Jeff
Friggin' Poet!grzy
Oct 23, 2002 8:58 AM
Yeah, well, the problem is he *did* consider both cranks - it is you that did not.