Shorter Cranks = Higher Seat Post ?
01-11-15, 10:42 PM
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Shorter Cranks = Higher Seat Post ?
This is probably a dumb question. I raised my seat post about 5 inches and have 170mm cranks. If I get shorter cranks, could I raise my seat higher?
01-11-15, 10:56 PM
#3
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Yes.
Do you have a goal for a higher seat post?
Consider when the pedal is at the bottom of the stroke.
Longer cranks = lower pedal at bottom ==> lower seat
Shorter cranks = higher pedal at bottom ==> higher seat
Do you have a goal for a higher seat post?
Consider when the pedal is at the bottom of the stroke.
Longer cranks = lower pedal at bottom ==> lower seat
Shorter cranks = higher pedal at bottom ==> higher seat
01-11-15, 11:01 PM
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01-11-15, 11:08 PM
#6
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The effect of 170mm vs. 175mm cranks is going to be pretty minimal (it's only 1/5 of an inch). I'd think you could get a more aggressive position with a change (or adjustment) of your stem that would be much more pronounced.
01-11-15, 11:13 PM
#7
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I'm not sure sticking your butt higher in the air makes you more aerodynamic.
You're better off dropping the handlebars.
Go with 140mm cranks, and it is about a 3cm difference.
You're better off dropping the handlebars.
Go with 140mm cranks, and it is about a 3cm difference.
01-12-15, 12:37 AM
#8
You are doing it wrong. Have you removed all the spacers between the headset and the stem (including the large conical spacer)? What is the length and angle of you stem?
01-12-15, 01:24 AM
#9
SuperGimp
I periodically ride with a friend of mine who is a dramatically stronger rider than I am - he prefers speedplay pedals because the stack height is ever so slightly lower and that lets him lower the seat a skosh, to get him out of the wind a little. Since he's so much faster than I am, I pretty much just say "uh huh" and keep pedaling.
01-12-15, 01:50 AM
#10
Ride it like you stole it
ding ding. Sticking your butt higher in the air isn't more aggressive.
I periodically ride with a friend of mine who is a dramatically stronger rider than I am - he prefers speedplay pedals because the stack height is ever so slightly lower and that lets him lower the seat a skosh, to get him out of the wind a little. Since he's so much faster than I am, I pretty much just say "uh huh" and keep pedaling.
I periodically ride with a friend of mine who is a dramatically stronger rider than I am - he prefers speedplay pedals because the stack height is ever so slightly lower and that lets him lower the seat a skosh, to get him out of the wind a little. Since he's so much faster than I am, I pretty much just say "uh huh" and keep pedaling.
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01-12-15, 02:30 AM
#11
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+1. The adjustment for shorter cranks is in the range of 5-10mm. You (the OP) have moved your seat by inches already... ?
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01-12-15, 06:47 AM
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I went to 165mm cranks to get more aggressive. I have a flipped and slammed -17 stem, and I am flexible enough that it is comfortable, but the problem was that I kept kneeing myself in the chest with 170s.
I now graze my jersey with my knees with 165s, so yes, shorter cranks did help me use a more aggressive position.
I now graze my jersey with my knees with 165s, so yes, shorter cranks did help me use a more aggressive position.
01-12-15, 07:11 AM
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01-12-15, 10:27 AM
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01-12-15, 09:19 PM
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I went to 165mm cranks to get more aggressive. I have a flipped and slammed -17 stem, and I am flexible enough that it is comfortable, but the problem was that I kept kneeing myself in the chest with 170s.
I now graze my jersey with my knees with 165s, so yes, shorter cranks did help me use a more aggressive position.
I now graze my jersey with my knees with 165s, so yes, shorter cranks did help me use a more aggressive position.
I'm sure you'll defend the set up but I really hope you're getting a full pedal stroke.
01-13-15, 03:34 AM
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Determinants of maximal cycling power: crank length, pedaling rate ... - PubMed - NCBI
Trained cyclists (n = 16) performed maximal inertial load cycle ergometry using crank lengths of 120, 145, 170, 195, and 220 mm. Maximum power ranged from a low of 1149 (20) W for the 220-mm cranks to a high of 1194 (21) W for the 145-mm cranks. Power produced with the 145- and 170-mm cranks was significantly (P < 0.05) greater than that produced with the 120- and 220-mm cranks.*
Note in this study highest peak power was around 165mm
Crank Length - Cervélo
01-13-15, 03:38 AM
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Determinants of maximal cycling power: crank length, pedaling rate ... - PubMed - NCBI
Trained cyclists (n = 16) performed maximal inertial load cycle ergometry using crank lengths of 120, 145, 170, 195, and 220 mm. Maximum power ranged from a low of 1149 (20) W for the 220-mm cranks to a high of 1194 (21) W for the 145-mm cranks. Power produced with the 145- and 170-mm cranks was significantly (P < 0.05) greater than that produced with the 120- and 220-mm cranks.*
Note in this study highest peak power was around 165mm
Crank Length - Cervélo
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