Tyre keeps poping under load?

Yeah. Don't seem to know what my mates problem is.

The motor runs on a bit to and there a little valve bouncing?

Any advice and ideas?

points are closed up

The Nut behind the wheel is the problem

Lee

Wholly smoke, Yass! Radial poping (or Pon-tiffing - as it used to be called in the days of cross-plies) of tires can still be a problem in some states (particularly the good ol' Bias-belt in the US) when the tires get too hot, or when going for a sudden spin. A cure can be for your mate to change to tires with less gripe - or as previously noted the wheel-nut can be slackened & point/s opened so much, that the point may be missed altogether.

uh