Belts don't really stretch, the sides wear letting them sit lower in the clutch sheaves. More likely that the outer belt cover is warped. If you don't have a clutch kit with the larger tires then you probably build more heat in the belt and clutches. With the larger tires you will add more load on the belt wearing it faster. We are all supposed to let our machines idle for a few minutes before shutting them down so the clutches get to cool some. Not sure about you but from what I have seen, most don't do it so that heat stays in the clutch cover and can warp it. Then the belt start wearing a hole in it.
Mine: 2018 Sportsman 850SP - 26" Bear Claw HTRs on OEM steel wheels(I really don't like the Aluminum ones)
Polaris Hand warmers, Mirrors.
Hers: 2007 Sportsman 500 EFI, Polaris Winch, 26" Bear Claw HTRs on Moose 427x Wheels. QSC Clutch Kit, Hand Warmers
2001 Magnum 325 MOSE 12" rear wheel conversion. 25" Sedona Coyote tires
2001 Magnum 325 Warn winch and Moose 60" plow
2017 Polaris Ranger 1000XP - Roof and front glass
SOLD 2004 Sportsman 600 Twin
Last edited by stave7119; 09-06-2018 at 05:48 PM.