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pedal bearings
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Does anyone have good information on the effect of pedal bearing 'looseness'? For example, I have some pedals that seem to have some resistance when I spin them with my finger and some others that are much more easy to spin. I suppose it doesn't make much difference, but maybe it does?





"mt evans in 2:07:33"
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Re: pedal bearings [hoehler] [ In reply to ]
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Bearing "looseness" is hard to judge. Some resistance can be indicative of a tight tolerance bearing which will not wobble, and that is good. A bearing that spins very freely can also have some slop in it, and that is not good. Bearings break-in over time. Especially when new, bearings are usually packed with grease, some of which can (unless they are sealed) work its way out as the bearing breaks in.

There is also the leverage factor to consider. Speedplays, for example, may seem harder to spin than a pedal like a Look, as your are pushing on a longer lever when you push on the end of a Look vs. Speedplay. There is also the question about the total number of bearings and what kind.

If you are worried, see if other pedals of the same brand spin easier that your "resistant" pedals. But remember, your fingers/hands are not exact measuring instruments. Unless it really feels tough to spin, I wouldn't worry.

"Non est ad astra mollis e terris via." - Seneca | rappstar.com | FB - Rappstar Racing | IG - @jordanrapp
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Re: pedal bearings [Rappstar] [ In reply to ]
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In Reply To:
There is also the leverage factor to consider. Speedplays, for example, may seem harder to spin than a pedal like a Look, as your are pushing on a longer lever when you push on the end of a Look vs. Speedplay.
i don't use speedplays, but can you explain this better? it intrigues me, but i am not sure i understand.





Where would you want to swim ?
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Re: pedal bearings [Greg X] [ In reply to ]
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When you twist or spin a speedplay, the point you are pushing on is maybe 1cm away from the center of the pedal, so the lever arm is 1cm. When you push on the end of a Look pedal, the lever arm is maybe 5cm. So you have 5x greater leverage, meaning it will seem "easier" to spin because of a leverage advantage. Speedplays are also very light, meaning there is less mass that comes into play once you start spinning it, which will also affect how it feels to spin the pedal.

Basically, the moment of inertia of the pedals about the pedal axle is very different, and that might be a large part of why it feels different to spin each.

"Non est ad astra mollis e terris via." - Seneca | rappstar.com | FB - Rappstar Racing | IG - @jordanrapp
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Re: pedal bearings [hoehler] [ In reply to ]
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The vast majority of the 'resistance' that you're feeling comes from seal drag and the rolling elements pushing through the grease.

Seal drag is a trade-off in terms of performance. If the seals are designed to for maximum contamination protection (good thing), they will also have a lot of drag (bad thing).

Cheers,

Matt T.
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Re: pedal bearings [Rappstar] [ In reply to ]
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ok, so are you saying that the ball of my foot is 5 times further away from the pedal spindle if i use look vs. speedplay.

there is a slight difference, of course. but 5 cm? only if i wear platform disco dancing shoes.





Where would you want to swim ?
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Re: pedal bearings [Greg X] [ In reply to ]
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No, no. Not when you are pedaling. When you spin it with your finger. Ball of your foot is in the same place -- over the pedal axle. Sorry. I was talking about feel in your hand when you spin it and leverage of your fingers pushing on the end of the pedal, which is what (I believe) hoehler was discussing. If you can feel a difference when you are pedaling, that is a problem. There is NO difference in leverage between pedals when clipped in...

"Non est ad astra mollis e terris via." - Seneca | rappstar.com | FB - Rappstar Racing | IG - @jordanrapp
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