I don't have any real experience- other than a vague desire to kinda get big fat tires on either of my ATBs. I thought the entire deal was clearance at the stays- I'm not entirely sure how the chain and or ring would be affected by tire size- as the tire is inside the chain stay and both the chain and the chainring are outside the chain stay.
I will say that I got a couple sets of Compass/Rene Herse tires on a couple of 700c bikes. They're awesome. People have said great things about the Rat Trap Pass tires- but I don't entirely know if they'd fit in an 80s ATB.
You should post pix.
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*Recipient of the 2006 Time Magazine "Person Of The Year" Award*
Commence to jigglin’ huh?!?!
"But hey, always love to hear from opinionated amateurs." -says some guy to Mr. Marshall.