I have ridden 500+ miles in 2 days on a Tomos ST, completely stock except for one small modification which the Sprint doesn't need. I would not try that on my '08 Sprint with a Biturbo, foam air filter, rejetted carb, and 22 tooth rear sprocket. It goes 43 mph, but I don't think it could keep that up all day. On a long trip, a stock engine is the only way to go. Both Kenda and Cheng Shin make tires for the Sprint/ST/LX that are much better than the Savas, and cheaper too. They won't fit a Tomos, but the best moped tire in the world is the Michelin Gazelle, and I've seen those priced cheaper than the Savas. Can't figure out what people like about those Savas. They're not much better than a bicycle tire. Peace. Jerry.