Cycling Equipment · Public discussion

Road bike vs. Mountain bike Q-factor

Started by Ron · · Last activity · 5 posts · 464 views

This thread is locked and is currently read-only.

Thread details

What we know about this thread

Original section
Cycling Equipment
Published
18 October 2004
Last activity
19 October 2004
Original author
Ron
Posts
5
Discussion status
Public discussion
Total views
464
Views / 30 days
0

The navigation and discussion metadata provide context. Posts remain in their original chronological order.

Showing posts 1–5 of 5
Posts remain in their original chronological order.

Text size
  1. I road ride about 300 miles a week and jump on my mountain bike a
    couple of times a month. When I ride my mountain bike my cadence
    feels awkward and I get pain in my knees. My road bike has 170 cranks
    and my mountain bike 175. In addition I notice my feet are wider
    apart on my mountain bike which is annoying. I measured the distances
    from the inside of my shoe to the frame center line. On my mountain
    bike it was 4 inches and on my road bike 3 inches. So on my mountain
    bike my feet are 2 inches farther apart.

    My road bike has Shimano Ultegra cranks and my mountain bike Shimano
    XTR cranks. Does anyone know how to get the q-factor more narrow on
    my mountain bike?

    thanks,
    Ron

  2. Ron said:

    I road ride about 300 miles a week and jump on my mountain bike a
    couple of times a month. When I ride my mountain bike my cadence
    feels awkward and I get pain in my knees. My road bike has 170 cranks
    and my mountain bike 175. In addition I notice my feet are wider
    apart on my mountain bike which is annoying. I measured the distances
    from the inside of my shoe to the frame center line. On my mountain
    bike it was 4 inches and on my road bike 3 inches. So on my mountain
    bike my feet are 2 inches farther apart.

    My road bike has Shimano Ultegra cranks and my mountain bike Shimano
    XTR cranks. Does anyone know how to get the q-factor more narrow on
    my mountain bike?

    thanks,
    Ron

    you could try something like a 2 ring ritchey compact 'cross crank. it
    has very low "q", but the reason most mtb cranks are high "q" is to
    allow for the extra width necessary for the chain stays to accomodate
    fat tires, so unless your frame is skinny in that department, you're
    kinda stuck.

    a number of folks in my neighborhood seem to be riding 'cross bikes on
    the mountain almost exclusively these days, so a different vehicle is a
    thought.

  3. [email hidden] (Ron) wrote in message news:<[email hidden]>...

    Quoted message said:

    I road ride about 300 miles a week and jump on my mountain bike a
    couple of times a month. When I ride my mountain bike my cadence
    feels awkward and I get pain in my knees. My road bike has 170 cranks
    and my mountain bike 175. In addition I notice my feet are wider
    apart on my mountain bike which is annoying. I measured the distances
    from the inside of my shoe to the frame center line. On my mountain
    bike it was 4 inches and on my road bike 3 inches. So on my mountain
    bike my feet are 2 inches farther apart.

    My road bike has Shimano Ultegra cranks and my mountain bike Shimano
    XTR cranks. Does anyone know how to get the q-factor more narrow on
    my mountain bike?

    thanks,
    Ron

    I sometimes use an MTB on the road during winter as a diversion from
    the normal racing bike and have felt a bit uncomfortable with the
    wider Q-factor. Here's what I'd suggest.

    (1)You can replace the MTB triple with a road touring triple. Using
    something like a customised Stronglight (110 BCD) you can even get the
    same gearing. This will reduce the distance "2 inches farther apart"
    by more than an inch.

    (2) Assuming you use the MTB on the road you can install a double
    chainring on the MTB with 170 cranks - then you should have the exact
    same Q-factor as the road bike.

    If you choose the second option you should make sure that the road
    cranks still clear the MTB chainstays (which are wider at the rear
    than on a road bike).
    You may also need a new bottom bracket for new cranks to maintain
    chainline but more often than not you can get away with what you have.

    -R

  4. jim beam said:
    Ron said:

    I road ride about 300 miles a week and jump on my mountain bike a
    couple of times a month. When I ride my mountain bike my cadence
    feels awkward and I get pain in my knees. My road bike has 170
    cranks and my mountain bike 175. In addition I notice my feet are
    wider apart on my mountain bike which is annoying. I measured the
    distances from the inside of my shoe to the frame center line. On
    my mountain bike it was 4 inches and on my road bike 3 inches. So
    on my mountain bike my feet are 2 inches farther apart. My road
    bike has Shimano Ultegra cranks and my mountain bike Shimano XTR
    cranks. Does anyone know how to get the q-factor more narrow on my
    mountain bike? thanks, Ron

    you could try something like a 2 ring ritchey compact 'cross crank.
    it has very low "q", but the reason most mtb cranks are high "q" is
    to allow for the extra width necessary for the chain stays to
    accomodate fat tires, so unless your frame is skinny in that
    department, you're kinda stuck.

    Good point. Perhaps shorter cranks- 170 since that what he uses on
    his road bike- would buy him a little extra clearance? A bigger
    problem might be whether the middle and granny rings clear the frame
    with a narrower Q crank. With aluminum frames this is more likely to
    be a problem than with other materials.

    I switched from an LX crank to a Ritchey 110/74 triple on my MTB, oh
    10 years ago now, and reduced the Q factor quite a bit. Clearance
    wasn't a problem on that bike (1993 Specialized StumpJumer M2),
    although it was close (the middle ring was about 2 mm from the
    chainstay). Still have the cranks, now on another bike, but sold the
    M2 years ago with the original LX crank and BB reinstalled.

    Quoted message said:

    a number of folks in my neighborhood seem to be riding 'cross bikes
    on the mountain almost exclusively these days, so a different
    vehicle is a thought.

    That ended up being my personal solution for about 8 years.

  5. [email hidden] (Rik O'Shea) wrote in message news:<[email hidden]>...

    Quoted message said:

    [email hidden] (Ron) wrote in message news:<[email hidden]>...

    Quoted message said:

    I road ride about 300 miles a week and jump on my mountain bike a
    couple of times a month. When I ride my mountain bike my cadence
    feels awkward and I get pain in my knees. My road bike has 170 cranks
    and my mountain bike 175. In addition I notice my feet are wider
    apart on my mountain bike which is annoying. I measured the distances
    from the inside of my shoe to the frame center line. On my mountain
    bike it was 4 inches and on my road bike 3 inches. So on my mountain
    bike my feet are 2 inches farther apart.

    My road bike has Shimano Ultegra cranks and my mountain bike Shimano
    XTR cranks. Does anyone know how to get the q-factor more narrow on
    my mountain bike?

    thanks,
    Ron

    I sometimes use an MTB on the road during winter as a diversion from
    the normal racing bike and have felt a bit uncomfortable with the
    wider Q-factor. Here's what I'd suggest.

    (1)You can replace the MTB triple with a road touring triple. Using
    something like a customised Stronglight (110 BCD) you can even get the
    same gearing. This will reduce the distance "2 inches farther apart"
    by more than an inch.

    (2) Assuming you use the MTB on the road you can install a double
    chainring on the MTB with 170 cranks - then you should have the exact
    same Q-factor as the road bike.

    If you choose the second option you should make sure that the road
    cranks still clear the MTB chainstays (which are wider at the rear
    than on a road bike).
    You may also need a new bottom bracket for new cranks to maintain
    chainline but more often than not you can get away with what you have.

    -R

    Thanks, I'll check the clearance between the cranks and the
    chainstays. I think there's quite a bit of clearance.

    Ron

Active in the last 60 minutes

Active in this thread

0 users · 0 guests ·0 bots ·0 total

No signed-in users are active right now.

No known search crawlers active right now.