Originally Posted by CafeRacer
11.4 : In my understanding the strap on an SPD-R was to basicly to perminantly pull the clasp shut so you didnt have to do it as tight. At least thats how I ran mine. But Ive also seen people use the MKS double straps thru SPD R's so more toe is covered too.
Cafe,
Not sure if I said differently. However the strap does two things on SPD-R's. First, it makes sure your cleat doesn't leave the pedal even if you twist far enough to release. Second, it takes up any slack in your shoe upper -- otherwise any room you have in your shoe becomes room for the foot to lift up away from the sole of the shoe. The strap doesn't have to be locked down hard as on PD-7400's to accomplish both these goals.
I don't think there's a lot of point in using double straps with SPD-R's unless one strap happens to be uncomfortable for you. The single strap will be sufficient to hold your cleat into the pedal long enough for it to re-engage. If Theo Bos could get away with a single strap (or Anna Meares, or Ryan Bayley for quite a while, or Ben Kersten) then I figure I can too. I actually have both single and double straps in my bag. For 500m time trials, I'll pull out the doubles. For olympic sprints and the like, I'll use singles. For massed start races, I may dispense with them altogether. It only takes 30 seconds to change.