1979 XT500 Tire Size & Fork Dust Seals

First post!...I'll be picking up a new to me 1979 XT500 this weekend.:busted: The ol gal is in good shape but she needs new tires. I see 3.00-21 and 3.25-21 listed as the front tire size with no consistency. 4.00-18 is definitley the rear. What is the OEM front tire size and the metric equivalent(s)? I want to order tires today so they are here by the weekend. I'll probably try the IRC GP1 if the front is a 3.00-21.

It also needs new fork seals. Looking at the parts diagram I see the 79 doesn't have dust seals. Will the 80-81 dust seals fit?


I run 3.00-21 front and 4.10-18 rear Shinko 244s on my '77 XT500 - the sizes of the original tires I took off were 3.00-21 and 4.00-18. I like the traction of the 244s, but the rear evaporates in 3000 miles (front lasted 7000 miles). Super cheap though - $71 a pair shipped from Motorcycle-Superstore. The 4.10-18 Shinko 244 seems to run a bit small (it's about 1/2" narrower than the original Bridgestone), so the next one will probably be a 4.60-18.

The GP1 has a very similar looking tread pattern as does the Kenda K270. I tried a K270 once and it was gone in 1500 miles!

Thanks. Kinda weird how actual tire measurements don't match the size description. Will take a look at the Shinkos

Went with the IRC GP-1 mainly since it was listed as OEM size and had good reviews. Anyone have any comments on the dust seals?

IRC tires are on. The 16 year old tires that were on there were a pain to get off since they were hard and dry but not dry rotted. Forks assembled and ready to go back on. I used a Dremel to cut the corners off a cheap 12mm socket to hold the damper rod so I could get the hex bolt off. Seals came right out after heating with a torch. I stripped, wet sanded and polished the tired looking lowers by hand using, 600, 1000 then Meguiar's Mag and Aluminium polish and they look great. Also replaced the upper steering bearings, regreased the lowers and cleaned everything up real nice (now my gauges look old and I need an ignition decal :lol:. Still would like to add some dust seals under the gaitors since I will be riding in a lot of sand. Hint Hint

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