A buddy of mine called me this afternoon stranded because the front wheel on his 1500 was locking up. He couldn't move the front brake handle on the right side of the handlebars. We took off the rotor cover and opened the bleeder valve and then pumped the handle a couple times and shot out some brake fluid. Everything seemed to be working fine then. Anybody else ever had this problem?

Never happened to me, but could be air in the line? When is the last time the fluid was changed? May want to do a drain, flush and fill..

There is a very small hole in the bottom of the master cylinder. This is there so that brake fluid may bleed back as the fluid heats and expands. This may have been the cause of the lock up if this hole was plugged.
Lets us on this forum know if this was the problem.