I have Holeshot XCT tires on my Tri-Z. I like them for trail riding BUT you are correct that they don't slide worth a darn. They hook up too well.
I haven't ridden anything with the Knarlys yet.
For what it's worth, a friend of mine switched from Holeshots to Razrs on his quad. He says they slide much better.
CURRENT RIDES:
1988 Tri-Z 350 Twin
1985 1/2 Tri-Z
1984 IT490
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