Yeah it was pretty common in europe. When I raced 1:8 I C 4wd in Germany, we did not have so much standing water as here in the US on the tracks. Given we has grass between lanes, there was less pooling and better run off. As Roelof stated the Tamiya Caps were awesome, and for a while Tamiya had some Super Grip Touring tires that had an awesome "rain style" tread that we would cut up and pull over the foams all while keeping a center rain sipe. If I can find them I'll post the part number, perhaps you may want to try a set. I think the racing in the rain was what taught me better throttle control.