[Mark_T]

Thanks for all the replies. I'll get a few 1/8" balls and fill in the gap.

I'm just getting back into cycling after a break of some 30+ years. I do most of my riding on the trails with a hybrid type bike in the summer and I just picked up a '88 Trek 560 for riding on the rollers over the winter (love the rollers!) and for longer rides next summer.