OK, I will be the first to admit that I should have done more research before doing this, but here goes:
I've been riding an old, almost vintage Bianchi for the past 10 years or so. Steel, downtube shifters, full Shimano 105, including PD-1056 pedals, heavy, but comfortable. I've always known that it's a little too large for me, but I'm used to it.
So I've been loaned a less old Fuji that's still steel, smaller, lighter, Ultegra, including PD-6700 pedals, and a much more aggressive profile. If I like the bike, I'll probably end up buying it.
So what I didn't look into was the pedals, but now that I have, I think I know the answer, but I'll still ask the question. Is there any compatibility between the SPD-SL cleat and the PD-1056 pedals, or between the Look Delta cleat (I think) and the PD-6700 pedal? I think they click in, but what I've seen is that it's not meant to really work. I'm thinking about finding some old PD-6402 or PD-6401 pedals so that I don't have to swap cleats when I want to change bikes or anything. Or is there some way around this?
Also, on a side note, is the float adjustable on the PD-6700? I think the combination of the PD-6700 with the yellow SPD-SL cleat seems to provide a little too much float for me. Or is the float all in the cleat, and the red SPD-SL cleat would provide no float? But maybe it's just too many changes for me...