I had a closed window track on my 98MXZ. Had no problems whatsoever. It was supposed to be slower due to the closed window rubber rubbing on the hyfax. Baloney! It helps to keep snow on the Hyfax when you run a dry area. I replaced the track on my 02 with a 1 1/4 before I ran it, so I can't tell you if there was a diff.
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