Originally Posted by
smontanaro
I went ahead and pulled the trigger for a pair of Veloflex ProTour 28s....
I mounted them on rims to stretch yesterday and pumped them up to 3.5 bar (~ 50 psi). When I checked on them this morning, my thumb test suggested they'd not lost much air. I thus conclude that the ProTours have butyl tubes instead of the latex tubes in the dear, departed Vlaanderen. *sniff*