Originally Posted by
choddo
Those shifters are for very old bikes or maybe some kids bikes. 22.8mm (7/8 in) - your bars are probably 1inch and maybe 1.25 inch where they meet the stem.
Saw an Amazon ad that said “will fit most bikes”. Absolute BS.
edit: although
this site claims the Revoshift shifters are also for 7/8in bars. Interesting.
Shimano don’t specify. Have you measured your bars?
22.2mm, or 7/8”, is the diameter that the vast majority of grip shifters fit, as well as other non-drop handlebar controls. The Denali is an outlier, using 22.2mm shifters on a drop bar, hence the split in the middle of the bar.