With SA reissuing their 3-speed fixed hub in the (hopefully) near future, I've been looking into making the switch to fixed. I'm riding an '85 Peugeot P8, which is on the lower end (or so I've heard - personally I think it rides fine). The thing I'm concerned about it the strength of the frame - will it be strong enough to stand the rigors of fixed riding, or should I start looking for a stronger frame? Any recommendations?