I've never had to buy a seat clamp/collar before. Well, I still don't, but I might want to bling up my bike(s). The OD of the seat tube on my HG SwSp is just under 32mm. So I assume the 31.8mm seat clamps I've found would be correct for Schwinns? I'd imagine this should be true for nearly all of them since they all used 26.8 seat posts. Thanks.