175mm or 170mm crank length
- Thread starter mattbrown
- Start date
Old School MTN BKR
Dirt Disciple
I have both and my knee hurts when I use the shorter 170mm. I have a very big leg.
Sheldon Brown wrote about it:
http://sheldonbrown.com/cranks.html
"I think people really obsess too much about crank length. After all, we all use the same staircases, whether we have long or short legs. Short legged people acclimate their knees to a greater angle of flex to climb stairways, and can also handle proportionally longer cranks than taller people normally use."
Sheldon Brown wrote about it:
http://sheldonbrown.com/cranks.html
"I think people really obsess too much about crank length. After all, we all use the same staircases, whether we have long or short legs. Short legged people acclimate their knees to a greater angle of flex to climb stairways, and can also handle proportionally longer cranks than taller people normally use."
jango
Senior Retro Guru
I have 175mm on my mtbs but I found 170s and 172.5s on road bikes hurt my knees so I changed 'em to 175s....whether that is due to crank length, roadie gearing or my crappy knees is open to debate....
at the end of the day it's what works for you but generally speaking the taller you are the longer cranks you require.
at the end of the day it's what works for you but generally speaking the taller you are the longer cranks you require.
Old School MTN BKR
Dirt Disciple
jango":ofis01b5 said:
I´ve done the same to my Caloi Montana, the cranks are 175mm, one piece BMX cranks ands it was a real pain to find them.
IbocProSX":ofis01b5 said:
I´m a pusher, but slowly turning to be a spinner due to knee problems.
FairfaxPat
Senior Retro Guru
cranks
I use 180mm cranks on my MTB and 175mm on my road bike (my road bike is actually my old MTB-1991 FUNK fitted with Conti slicks). In my neighborhood we have a lot of mountains and big hills in the dirt and I find the longer crank arm makes it easier to climb the big hills, while on the road I find the shorter 175mm length is easier to spin at a higher RPM. The roads tend to be much more evenly graded, thus promoting a higher RPM spinning style, while in the dirt the sudden short extra steep bits are easier to handle with the longer lever of the 180mm arms. You must have longish legs to use 180's however.
I use 180mm cranks on my MTB and 175mm on my road bike (my road bike is actually my old MTB-1991 FUNK fitted with Conti slicks). In my neighborhood we have a lot of mountains and big hills in the dirt and I find the longer crank arm makes it easier to climb the big hills, while on the road I find the shorter 175mm length is easier to spin at a higher RPM. The roads tend to be much more evenly graded, thus promoting a higher RPM spinning style, while in the dirt the sudden short extra steep bits are easier to handle with the longer lever of the 180mm arms. You must have longish legs to use 180's however.
made a pretty long trip through central asia in 1996 (3000+ miles) .... found out I had 2 different crank lenghts (170 left side and 175 driver side :? ) when I dismantled the bike after the trip, swear I didn't notice a thing during this trip .... sort of an ostrich thing maybe, if you don't notice it, it's not there 
