ive got werx connection ones on my 426, all they seem to do is make it harder to line all the tank and rad scoop bolts up after you taken the fuel tank off, im thinking of puttin them on ebay or trying to swap them for a set of ally frame guards!!!
me and my mate we both got 426s his locked up last year, no reason, coolant ok, oil just been changed, it was striped down by a very reputable mx shop here in the uk, no fault wwas found and the only advice that was given was while the engine was in bits to change the cam chain, once it was reassembled it has run fine till this day! pewrhaps its the yzf form of arthrithus!!!