Saw a '78 RD400 at a local cruise-in Saturday night with 4.10-18 Dunlop K81s on it, I think. Didn't see any sign of interference (raw spots on tires), but they DID almost look out of proportion. Given that both 3.00-18s and 3.50-18s are difficult to find in quality tires on this side of the pond, what's the next conventional size up from 3.00-18? I like a slightly narrower tire on front than on back, and if the ol' K70 is still made in 4.10-18, that's what's going on back of my XS400E next.

Saw a '78 RD400 at a local cruise-in Saturday night with 4.10-18 Dunlop K81s on it, I think. Didn't see any sign of interference (raw spots on tires), but they DID almost look out of proportion. Given that both 3.00-18s and 3.50-18s are difficult to find in quality tires on this side of the pond, what's the next conventional size up from 3.00-18? I like a slightly narrower tire on front than on back, and if the ol' K70 is still made in 4.10-18, that's what's going on back of my XS400E next.

I've got the maxxis 3:50 on front and 4.00 on rear. for the flat track look I don't think I could go bigger on the rear

check out the end my flat tracker thread in the street bike section for the tyres. bear in mind the bike is slightly raised by 2"