Should work fine. You may need to adjust the spacing on the rear axle in order to have the RD travel smoothly to the smallest cog. I had this issue when replacing an old Suntour 6 speed freewheel with a new Shimano 6 speed. The new Shimano was a little wider and caused a minor issue. No big deal to fix it. You can run your shifters in friction mode and have no issues, or you might be able to squeeze out another shift with your shifters. I had Suntour Accushifters on a Schwinn and I was told that you can get the seventh shift, but there will be no click or detent.