2023 Yeti SnowMX 129FR belt snap after a few hours?

[mylastknight]

I was riding yesterday and took a steep hill climb when the 28mm Yeti belt snapped in half. The belt showed absolutely no signs of wear on the sides of the belt only snapped. I replaced it with a new backup belt and took the same hill with no issues. I checked the belt originally when I got the bike a couple times but not after a couple rides which I now plan to do every ride. With the new belt replacement I checked a few times since and tension is perfect. I wanted to see if anyone else has snapped a belt when alignment is good and tension is good too? I will give it another go today and have one more backup belt left.

Just for info: I have KTM450-SXF 2022, C3 bars, selkirk armor, stock sprocket, upgraded chain.

Concerned for this new Yeti FR129.

 

[C3 PowerSports]

They usually only break like this when they're too tight. If it was slightly too tight when cold while running the kit the gears keep warming up the harder you run the more they warm up so it makes sense on a harder climb they just warmed up too much and aluminum grows quite a bit with temperature and this can cause the belts to snap just like this. Check the belt tension once after a lot of really fast trail miles or a long high torque climb. It should still move at least half of the belt deflection clip pushing hard on the belt with two thumbs. For initial tension it should push the whole clip length and I run slightly looser and go almost an eighth over that when at 60 to 70 degrees F room temperature.

I put on over 200 hard hours a year and haven't broken about in 6 years and was on a bike really bad neutral on a bike with a terrible transmission that would pop out of gear in third when at wide open throttle hit the rev limiter for a split second and then hammer into second gear. That's a situation where I expect the belt to break. Other than something like that I think these belts should never break on a snow bike if the tension is right and they don't ingest any snow.

Sorry for the long reply just wanted to share my experience. Feel free to PM me if you want any more specific info

 

[mylastknight]

This is was just the insight I was looking for. I purchased my backup from C3 so good to see your reply. I have checked it several times with the two thumb method. Before the ride, trail riding, middle day during lunch, now that I am on the new belt. My issue is that I wish I would have monitored a few times before so I was aware but can't go back in time.. Going to my dealer tomorrow to hope I can get a couple more for backups. I hope I never have too use them but I want to try what you said, after a strong hill climb the sprockets warm up and I want to see if that has any bearing on belt tension. I should have also mention that during the breakl I was shifting down from 2nd to 1st. I have been a bit more careful where I maintain the gear or slightly let off throttle when shifting. So now I have a 12 hours on the bike so 6-7 hours on the new belt. I'll repost if I have any more trouble.

 

[Chadx]

@mylastknight Just for reference, can you post a picture of where the belt is riding on the outer edge of each pulley and the tensioner (understood that tension has outer lip, so that image may be moot)?