three bikes three different sized cranks two knees that might suffer
Results 1 to 7 of 7
  1. #1

    Reputation:
    Join Date
    Nov 2004
    Posts
    44

    three bikes three different sized cranks two knees that might suffer

    Hey there. Currently I've got three bikes that I love, a road bike, a SS cross bike and an SS mountain bike. On these bikes sits three different size cranks, 175 on the road bike, 180 on the mountain bike and 170mm on the cross bike. This setup wasn't really my design, these cranks came on the bikes when I got them. Each of the cranks does serve a good purpose for the type of riding that I do on these bikes; I need the torque of the 180's on hte SS mountain bike, I like the easy spinning on the cross bike because my route to work is pretty much flat, and the road cranks feel pretty good. The mountain bike and the cross bikes are both new so I haven't riden with this setup to much yet. Right now the cross bike is my main ride, I use it for commuting, but when riding season picks up again I'll be riding all three bikes alot. I've had knee problems in the past that whent away when I started cycling and I was wondering if the old knee problem is going to flair up again using these cranks. Should I compromise and get the same sized cranks on all my bikes or am I going to just get used to this? Is my spin going to be compromised by switching between different sized cranks or is it going to get smoother by learning to spin smoothly in different sized cranks? Has anyone out there used a setup like this on thier bikes?

  2. #2

    Reputation:
    Join Date
    Nov 2004
    Posts
    492
    I don't see how this would create knee problems assuming your saddle height is allowing a 10 - 15 degree bend in your leg at the bottom of the stroke. Watch torquing on your mtb. Too slow of cadence with a lot of pressure could stress the knee. I think reasonable gearing will keep things ok. BTW most mbt crankarms are a little longer.

  3. #3

    Reputation:
    Join Date
    Oct 2003
    Posts
    195

    different opinion

    most people on this board think that 5mm here or there doesn't really make a difference. in my experience switching between 175 on my road and 170 on my track / fixed was a noticable difference for me, i couldn't dial in spinning on the 175s, my knees were always out of whack. i don't think 175 is an acceptable size for me though. i decided to drop the range to 170 and 172.5, which i think works a lot better for me. but everyone's different.

  4. #4
    NeoRetroGrouch
    Reputation: TurboTurtle's Avatar
    Join Date
    Feb 2004
    Posts
    6,491
    Quote Originally Posted by fast klein
    Hey there. Currently I've got three bikes that I love, a road bike, a SS cross bike and an SS mountain bike. On these bikes sits three different size cranks, 175 on the road bike, 180 on the mountain bike and 170mm on the cross bike. This setup wasn't really my design, these cranks came on the bikes when I got them. Each of the cranks does serve a good purpose for the type of riding that I do on these bikes; I need the torque of the 180's on hte SS mountain bike, I like the easy spinning on the cross bike because my route to work is pretty much flat, and the road cranks feel pretty good. The mountain bike and the cross bikes are both new so I haven't riden with this setup to much yet. Right now the cross bike is my main ride, I use it for commuting, but when riding season picks up again I'll be riding all three bikes alot. I've had knee problems in the past that whent away when I started cycling and I was wondering if the old knee problem is going to flair up again using these cranks. Should I compromise and get the same sized cranks on all my bikes or am I going to just get used to this? Is my spin going to be compromised by switching between different sized cranks or is it going to get smoother by learning to spin smoothly in different sized cranks? Has anyone out there used a setup like this on thier bikes?
    Using a low cadence on my SS affects my knees. I feel no difference between the 165mm and 175mm that I have on different bikes. - TF
    "Don't those guys know they're old?!!"
    Me, off the back, at my first 50+ road race.

  5. #5
    RoadBikeReview Member
    Reputation:
    Join Date
    Feb 2002
    Posts
    21,324

    Making a difference

    Quote Originally Posted by wooden legs
    most people on this board think that 5mm here or there doesn't really make a difference.
    It might be more accurate to say that most people think you can adapt to the 5 mm difference, particularly given that there are three fairly different uses for these bikes. The most accurate statement would be that there is no way to predict what effect the difference will make. Some people say they can't tell the difference, some say they can tell the difference but it doesn't mean much, and some people say the difference means a lot. If the studies on crank length have shown anything, they have shown that the human body is highly adaptable and that it is not possible to predict the effect of different lengths.

  6. #6

    Reputation:
    Join Date
    Nov 2004
    Posts
    11
    the crank length is less of an issue than the amount of stress that you may place on your knees trying to spin your SS mountain bike up steep terrain. without lower gear options, you are left with only leg strength to get you up those steep hills. that may hurt your knees much more than 5mm crank differences.

  7. #7
    FTMD
    Reputation: FTMD's Avatar
    Join Date
    Sep 2002
    Posts
    283

    ss v. geared

    I have recurring knee issues and find that my knee hurts less on my ss mtb than on my geared mtb. On the ss, I stand to climb. On the gearie, I shift down and spin, thus placing more shearing forces on the front of the knee. Standing to climb doesn't place those same shearing type forces on the kneecap.

    Whatever the reason, I am riding my ss more and more and avoiding the gears.

    This is my experience, and YMMV.

    D

Similar Threads

  1. Washington Post reports on decline of US bike industry
    By Orfeo in forum General Cycling Discussion
    Replies: 19
    Last Post: 06-29-2005, 12:01 PM
  2. 2005 cross bikes
    By flyweight in forum Cyclocross
    Replies: 24
    Last Post: 03-05-2005, 11:28 PM
  3. Huffy kids bikes throwing chains
    By 633 in forum Bikes, Frames and Forks
    Replies: 4
    Last Post: 11-29-2004, 09:04 AM
  4. My new, overpriced, slow-handling ride.
    By Tachymetres in forum General Cycling Discussion
    Replies: 39
    Last Post: 06-12-2004, 07:04 PM
  5. TT bikes VS Aero Road bikes
    By CARBON110 in forum General Cycling Discussion
    Replies: 18
    Last Post: 05-06-2004, 08:31 AM

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  

THE SITE

ABOUT ROADBIKEREVIEW

VISIT US AT

© Copyright 2020 VerticalScope Inc. All rights reserved.