Originally Posted by
atmdad
I'm looking to upgrade my old 14-28 five speed to a new 13-28 seven speed.
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Spacing is not a problem
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Are you sure? Five-speed is generally 120mm OLD, while the "normal" six and the "narrow" seven are both 126mm OLD. You can spread steel stays to accommodate, but you may need to lengthen the drive side of your hub axle with spacers.
That said, I love old SunTour freewheels, but recently switched to ramped freewheels, one Shimano and one SunRace. I don't care for the way Shimano mounts the two largest cogs via rivets to the smaller ones. But they both shift really well.