I have used only gates booster Belts.
I believe this is the size:with angle
1025 x 28.9mm x 30
length x width x angle
Gates boosters models:
9802-41811
9802-40811
I have compared then side to side and cannot see a difference.
I also searched online, but can't find any info about these belts.
Regarding longevity, I am happy with their performance and reliability.
I have used 2 belts over 35 000km and still going strong.
You have to strip the CVT, both clutch and variator to examine all parts to see if wear is excessive.
There is an older free manual online, Italian headings, a Pdf page/chapter, but English contents. That will give you the tolerances.
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