Ultimax XS821 belts anyone having issues with them

[treemongrol]

Ive got an 09 154xp, usually run xs803's or bombardier belts, never had a problem with them, average around 1100k's with either. Had 2 xs821 that I was told was the upgraded belt for the xp, put one on dec 18, blew it on the 19th peeled chunks off the top, put the other on rode the rest of the day and also part of the 27th with it and it shredded also, had picked up 2 new 803's prior to going to Mcbride on the 26th, put the 803 on and its still on the 821's if they had 70 k's on them that would be pushing it, the 803 has just over 600ks from the week in Mcbride and they aren't easy km's and it still looks new, one thing I noticed is that when running the 821's I could only get 40 to 45km track speed and couldn't keep rpm. With the 803's i get 65 to 70km trackspeed consistently and hold 8200rpm thru out the pull and it doesn't matter how many pulls I make with them it consistently holds rpm and track speed. I'm running 20/45 gearing, clutches serviced prior to going up and alignment is good, has anyone else had same issue with the xs 821?

 

[Got boost want snow]

Jmo!!! I would never put a dayco rag on anything I own. I have run all the aftermarket belts at some time or another and have found OEM out does all of them. But this is just the experiences I have had with them.