Q factor / pedal spacing
09-21-20, 07:15 AM
#1
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Q factor / pedal spacing
I noticed that my right pedal is 1 cm further from the center of the frame than my left pedal.
Should I just keep riding or do I need to come up with a fix?
What method would you use to fix this?
Should I just keep riding or do I need to come up with a fix?
What method would you use to fix this?
09-21-20, 01:40 PM
#2
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Drive side offset is typically larger than non-drive side offset to accommodate the chainring(s). Is it causing a problem? If not, ride on. If so, there are pedal extenders you can use to move the non-drive side pedal further out to match the drive side offset.
09-21-20, 01:49 PM
#3
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The lack of drivetrain stuff on the non-drive side means that the crank arm is able to sit closer, doing this is a way to reduce q-factor. If it's not bothering you, it's not something that needs to be "fixed."
09-21-20, 01:54 PM
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My knees prefer as low a Q as possible. I seek out bottom brackets that place the left crank close to the chainstay. With a triple, this is quite asymmetrical. My body doesn't even notice.
Shimano BBs are typically symmetrical or very close. I like that they are cheap, very well made and very reliable but I've stopped using them because I have to live with my knees. When I set up a another bike, I install the Shimano, look at the clearances, cxalculate how much shorter a spindle could be and the assymmetry, then seek that out.
Ben
Shimano BBs are typically symmetrical or very close. I like that they are cheap, very well made and very reliable but I've stopped using them because I have to live with my knees. When I set up a another bike, I install the Shimano, look at the clearances, cxalculate how much shorter a spindle could be and the assymmetry, then seek that out.
Ben
09-21-20, 02:28 PM
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My knees prefer as low a Q as possible. I seek out bottom brackets that place the left crank close to the chainstay. With a triple, this is quite asymmetrical. My body doesn't even notice.
Shimano BBs are typically symmetrical or very close. I like that they are cheap, very well made and very reliable but I've stopped using them because I have to live with my knees. When I set up a another bike, I install the Shimano, look at the clearances, cxalculate how much shorter a spindle could be and the assymmetry, then seek that out.
Ben
Shimano BBs are typically symmetrical or very close. I like that they are cheap, very well made and very reliable but I've stopped using them because I have to live with my knees. When I set up a another bike, I install the Shimano, look at the clearances, cxalculate how much shorter a spindle could be and the assymmetry, then seek that out.
Ben
Meanwhile, I’m running my first gen DA cranks on the Schwinn road frame. They were made for low profile JIS taper and came with an asymmetrical 112mm crank axle. Using a standard JIS BB works, but they stand a few mm further out which actually works ok with a 110 BB on this frame. However, I had to throw on 2 mm worth of spacers on the drive side of the BB to get the right spacing and asymmetry and just clear chain stays nicely on both sides. Ends up with a Q-factor of 136mm.
Otto
Last edited by ofajen; 09-21-20 at 02:34 PM.
09-21-20, 03:08 PM
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Nice work!
My low-Q campaign has been taking a breather. So far:
my geared TiCycles, triple 90speed. 143 with old Sugino (probably 5-speed) cranks and 105 Phil Wood BB
fix gear TiCycoles, SUgino 175 - straight track - 132
Mooney, 1/8" chain fix gear with triple, 135 with old road Sugino cranks, Phil BB, chaniline as far inboard as possible.
Trek fix rain/city gear 137 with nothing special road Sugino cranks and track chainline.
Raleigh Competitoin triple 150 with 7-speed Sugino crankset, Shimano (I believe) BB still. (This bike was 165!)
So all my primary bikes are good to excellent. Knees love it!
Ben
My low-Q campaign has been taking a breather. So far:
my geared TiCycles, triple 90speed. 143 with old Sugino (probably 5-speed) cranks and 105 Phil Wood BB
fix gear TiCycoles, SUgino 175 - straight track - 132
Mooney, 1/8" chain fix gear with triple, 135 with old road Sugino cranks, Phil BB, chaniline as far inboard as possible.
Trek fix rain/city gear 137 with nothing special road Sugino cranks and track chainline.
Raleigh Competitoin triple 150 with 7-speed Sugino crankset, Shimano (I believe) BB still. (This bike was 165!)
So all my primary bikes are good to excellent. Knees love it!
Ben
