Ken - Please understand I take no joy in raining on anybody's parade... But, the first version Fox 19 3 bolt had a 2 piece crank, with the crankpin pressed into a hole in the crank disc. They fail when the hole opens up and the pin works loose. The only way to know is to break it down and look at the crank for evidence of the hole. The second version is visually identical to the first, and its impossible to tell which you have without disassembly. If its a one piece crank, go ahead and enjoy a clown, Jr. nobler or Jr. flite streak, but please don't blow it up if its a weak one. Tom H