Frank X said:Quoted message said:Cheaper, larger platform, release in both directions. Frogs only
release when foot is twisted in one direction (heels outwards, I
think) -- which I find a scary prospect for the event of crashes,
where feet or bike could twist in either direction.
My current SPDs release only in one direction and I'm happy with that.
Are you sure? I thought all SPDs can release by twisting inwards as well
as outwards, even if that feels unnatural and more force is required. I
think some multi-directional versions also release simply by pulling
upwards -- that's not what I mean.
But in any case, you may be perfectly happy in normal use with
one-direction but you won't always have the opportunity to deliberately
twist feet in a crash. Getting stuck to the bike or tangled up in it can
result in greater injury. I know of one case where a rider seriously
injured his leg because of this problem. The rider or the bike tends to
twist to one side naturally during a fall but it can be to either side!
Quoted message said:What does larger platform mean,
Simply that the pedal is larger, with a larger area for the cleat to
contact. This just tends to feel more comfortable efficient, even I find
with extremely rigid soles (which doesn't make sense according to the
theories but seems to be the case in reality with me).
Quoted message said:is that likely to be better for my knees?
I don't think so. That's where the large amount of float of Speedplays
could indeed help you, although Look pedals provide up to 9 degrees* which
is quite a lot. You get about 5 degrees with SPD. Time pedals also have
more float than SPD--another option for you to consider: I think they have
models compatible with SPD shoes.
* albeit with quite some friction with standard setup, but this can be
vastly improved with grease and altering cleat rubber thingy (please see
other reply).
~PB