Firstly ... G-day all. ( yes Australian ) I've recently evolved from a cafe racing CBR900 Jockey to full blown reckless/fearless trail basher,and am in need of some friendly advice.( haven't ridden trail bike in years ) Just aquired a 1999 wr400 and are using it for commute to work and destruction of local golf courses on weekends. In the scrub the damn thing is lethal,takes great pleasure in making me crap my dacks every chance it gets.It's road manners however are a little dishartening. Cruisng at around 60 to 90 kms/hr I'm getting a nasty vibration coming in at intervals of 2 seconds and lasting for only 2 seconds. ( sorry,only way to describe ) the whole bike shudders.worse at higher speeds. I am running road/off road rear tyre and off road front.( front to be changed to road/off road when i get chance ) Apart from buggered suspension can't think of much else to try. idea's or experiences please ???