s4one

My previous bike was a Look555 with a standard BB, my pedaling was fine and I was able to sprint the living heck of of the bike.

My current bike is a 2010 supersix with bb30. What I noticed is that I cannot do full out sprints and my knee does not track well with my foot (feet are closer to the frame than my knee). Here is my conclusion, since the normal bb on the Look used external bearings, there was about half an inch before the crank came in contact with the BB for the bearings. Therefore, my legs will be spaced wider apart.

Now on the Supersix with the bb30, it does not have the external bearings meaning the cranks are half an inch (more or less) closer to the frame. Thus, my feet are placed closer to the frame, not allowing me to spin correctly.

What I am going to do first is adjust my cleats so that my feet are set farther form the frame so that my feet and knees can track right, my shoes allows this (northwave) can adjust the cleat from right to left.

If this change isnt significant enough, I was thinking of changing pedals to Speedplay zeros and opt for a longer spindle. I currently use Look Sprint pedals.

Does this sound logical?

Thanks in advance.

BotByte

Yeah it does kinda make sense. I know I can full out sprint on my mountain bike, but not on my road bike. Weird. But then I can hoof it on my road bike a lot better though.

Bob Dopolina 

What you are talking about is Q-Factor. Basically it is the distance your feet are apart on the bike (really the distance between the outer surface on the crankarms where the pedals thread in).

When manufacturers went to external bearings they altered the angle of the cranks arms to maintain, or in some cases narrow the Q-Factor. My guess is the difference is less than you think.

Having said that I'm not sure why everyone is convinced that narrower is better. I really don't like super-narrow Q-Factors and I am only comfortable shifting my cleats to the inside essentially widening my Q-Factor. You may be in a similar situation.

Other than BBs and frames are all other factors the same? Were you careful to duplicate the positioning on the BB30 frame or did you make any adjustments?

s4one

No I did not duplicate any positioning.

I set up my cleats like you. I normally set them on the inside more, so much that even the edge is hanging off the hard part of the shoe bottom. However, recently I changed my cleats for new ones and placed them in the center, to see how things are. Anyways long story short, I need to set up my position where my feet are farther apart from the frame/bb/crank whatever...

Like I said I will first adjust my cleat and see if this is going to make a difference, if not. I will like to change to a pedal with a longer spindle (speedplay).

Note, one thing that I noticed was that when I rode my Look 555 with the normal BB, my foot would have no clearence issues. However, on the supersix bb30 frame, my shoes skim the crank arm from time to time (not always) but enough that there are visual scratch marks on both cranks from my shoes scratching the crank arm.

Thus, I think I need to try a longer spindle or adjust my cleat to the inside more or both.

Thanks for reading and helping.

mmmdonuts

Measure the Q on your current bike. Measure or lookup the Q on your old bike. Then you'll know for sure.

Steve530

You can buy pedal extender if necessary.

WestCoastDan

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