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Rollin' a fatty
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Discussion Starter · #1 ·
I've been using a set of Deore cranks with a XT BB and a Salsa ring since I built my current ride (Kona Unit).

Recently I've been having knee pain and by coincidence noticed that my cranks are 170mm, I'm 5'8" BTW. I have a 175mm XT set on my geared and don't get any knee pain when I ride it (not very often). Could it be that the shorter crank arms are causing the pain and if so is there a good but affordable crankset that I can get my hands on?
 

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DiRt DeViL said:
In road cycling, shorter crank arms generally equate to more spin so your knees could be working more. Are your pedals the same, with the same degree of float? I would look into the least common denominator between your two bikes.

I would quell your upgradeditis until you figure out what the problem is and how to fix it. Dropping any amount of money and not solving the problem is money wasted IMO.
 

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dir-T said:
aren't wrecked knees a side effect or riding a SS or is that just a myth to keep the rest of us on gearies?
That's what I would like to know. Some guy on the trail dismissed SSing the other day saying something like 'just wait unless your knees start to go'. My knees seem to do better on a SS. I thought because you stand more, you are less hard on your knees. Now if you sit all the time I see where it could be a problem.
 

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Rollin' a fatty
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Discussion Starter · #7 ·
zanq said:
In road cycling, shorter crank arms generally equate to more spin so your knees could be working more.
I'm a masher.

zanq said:
Are your pedals the same, with the same degree of float? I would look into the least common denominator between your two bikes.
Same pedals, same shoes (just 1 pair). The only difference is the crank arm length and that the SS is a HT and the geared an FS.

zanq said:
I would quell your upgradeditis until you figure out what the problem is and how to fix it. Dropping any amount of money and not solving the problem is money wasted IMO.
Agreed
 

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DiRt DeViL said:
I ride most of the time seated, stand ocassionaly but not often.
I don't know man. If you are doing some climbing and you are straining while seated I think it will be hard on your knees. You might try standing some while climbing. I would be especially curious if while climbing on a geared bike, do you tend to sit and spin in a low gear, or do you put forth more effort in a high gear (similar to SSing).
 

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DiRt DeViL said:
I ride most of the time seated, stand ocassionaly but not often.
I would say crank arms are probably the problem.

If you are seated, greater effort will be needed to climb the same hill using shorter cranks (if all else is the same). You have less leverage to put power into the drivetrain, so you have to make that up physically, putting stress on the body.

Can you swap your cranks around and do a test?
 

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Rollin' a fatty
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Discussion Starter · #13 ·
Eltbee said:
I would be especially curious if while climbing on a geared bike, do you tend to sit and spin in a low gear, or do you put forth more effort in a high gear (similar to SSing).
I almost always find myself spinning, I pedal totaly differently when swapping bikes. Mash and the ocassional stand on the SS and spin on the geared when climbing.
 

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Retro Grouch
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I'm coming from the other direction..

DiRt DeViL said:
I've been using a set of Deore cranks with a XT BB and a Salsa ring since I built my current ride (Kona Unit).

Recently I've been having knee pain and by coincidence noticed that my cranks are 170mm, I'm 5'8" BTW. I have a 175mm XT set on my geared and don't get any knee pain when I ride it (not very often). Could it be that the shorter crank arms are causing the pain and if so is there a good but affordable crankset that I can get my hands on?
Just picked up a set of these cranks from ebay for 10 bucks (plus $5.50 shipping). Add a chain ring, nuts and a couple of bolts and you have an inexpensive experiment. I'm 5'10" (32" inseam) and I'm using 180 cranks. I've used 166.5 mm cranks on my road fixie and they make climbing quite difficult. But the 180's are sometimes a little difficult to turn over, so I thought I'd try some 175mm just for kicks.

1G1G, Brad
 

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If you are seated most of the time.....

DiRt DeViL said:
I ride most of the time seated, stand ocassionaly but not often.
You should check your pedal to seat distance to make sure there is not a vast difference between your multi bike and your SS. You may have to raise your seat, 5mm may not seem like a lot but that difference is exagerated in your knees. I agree with the other poster that you should find the cause and not start changing parts.
 

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Retro Grouch
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You can go will BMX cranks, but they either need to be Euro BB or you can get a euro conversion kit (new bb that works with your spindle).

I am currently running some Profile 180s. To get a good deal on bmx cranks, check bmx races or web sites. They are the ones who will have sets laying around and sell lower priced. It all depends on where you look.

Something else to check. Since you are climbing seated, make sure not only the height is the same, but the front to back is the same. If you sit farther back/forward on you SS, it can make for some painful knees.

I have had a lot of problems with my knees hurting in the past. Since I have started riding SS they are getting stronger. Just make sure not to over do it if they start to hurt. Let them heal some before the next ride.
 

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gatman said:
You can go will BMX cranks, but they either need to be Euro BB or you can get a euro conversion kit (new bb that works with your spindle).

I am currently running some Profile 180s. To get a good deal on bmx cranks, check bmx races or web sites. They are the ones who will have sets laying around and sell lower priced. It all depends on where you look.

Something else to check. Since you are climbing seated, make sure not only the height is the same, but the front to back is the same. If you sit farther back/forward on you SS, it can make for some painful knees.

I have had a lot of problems with my knees hurting in the past. Since I have started riding SS they are getting stronger. Just make sure not to over do it if they start to hurt. Let them heal some before the next ride.
gatman best avatar ever!
 

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Steamroller
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Seated climbing on an SS?

DiRt DeViL said:
I almost always find myself spinning, I pedal totaly differently when swapping bikes. Mash and the ocassional stand on the SS and spin on the geared when climbing.
Seems like that may be your issue. Climbing while seated on an SS is going to take more effort and the short crank won't help. You may be sitting and mashing when you should be standing and mashing. My vote is stand more and get longer cranks, or at least swap them so the 175s are on the SS bike.
 
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