Ok, so I have a plan to modernise myFZX750. Its a grey import and for what its worth I love riding it and the look of it. BUT, I don't like the 16" front and 15" rear tyre choices, its pretty damned limited. So my goal is a pretty standard upgrade for this bike overseas. My plan is to fit a YZF600r ( I have one) front end, wheel and brakes. Its a bolt on fit, same bearings and shaft. I would, however, need to drill and weld the headset to take risers ( not an issue as I'm a fitter and turner by trade). I will also be fitting an XJR1300 rear end, this is also a direct bolt on ( with a pre 04 swingarm). these upgrades will give me 4 pot brakes and stiffen her up somewhat and, most importantly, give me a better range of tyre selection in 17". I know all of these mods work as I have researched, measured and checked a lot over the last 3 months. What I'm a little confused on is whether I need an engineers Certificate to do it. anyone done similar or understand the TMR info better than me? the way I read it I thought that the front should be fine. but Don't want an insurable, unregisterable bike. Thoughts?