Posted November 05, 2002 - 04:32 AM
They are moose <sp> tubes. A soft foam tube that takes the place of your normal tube. While they do not go flat there is some down sides to them. They are more expensive, they are tough to put in. It takes lathering them up with grease and more wrestling than normal. They have a limited life span. The foam breaks down and then it feels like your riding on flats. They are a little heavier. The only people that really use them are serious off road racers with bigger budgets than most of us. MX guys don't use them. There is however a system of a foam insert with a small tube in the middle that some MX racers have played with.