The Yamaha FZR750 Engine Rebuild
Right from the first day I saw this bike I knew it was doomed, I mean it's a indescribable color and the engine makes sounds I never hear before.It's another one of those bikes I just bored everyone about how good it was, and how if everyone bought one of these instead of being obsessed with style and getting an Yamaha YZF-R1 they can't control they'd all be better riders blah, blah blah.
But when all is said and done, it is still hand painted in the most ugly colors I ever seen, which is a bit like going our with a red headed bird, cos we all know the cuffs and collars match. Anyway, the Exup (Exhaust Ultimate Power valve) was so typically Yamaha I should have known it wasn't going to stand my imbecilic lofting techniques even after a decade of refinement. With a gear shift that feels like it's made out of dental amalgam, and a clutch basket that sounds like its full of broken Chinaware, the Exup and indeed the whole Yamaha range has always been the most frail of 4-stroke engines.
I'm actually really amazed that no-one, or indeed the public in general, has really twigged just how hideously unreliable Yamaha 4-cylinder engines are. It's not that they just simple wear out, which is obviously why they make the Yamaha YZF-R1 and the Yamaha YZF-R6 over-steer so markedly, knowing that most riders are going to write their bikes off long before they explode.
The YZF was actually a couple of millimeter out geometrically itself. Compared to the original EXUP, it wasn't such a neutral steerer, but I must say getting back on one reminded me just how right Yamaha got it in 1986 and how much of a copy the Blade really was. And even got 6-pot brakes.Just like every 750cc or 1000cc EXUP before it, it didn't take many flat out runs to the printer or much general hatred inflicted by those who considered they'd been used, abused, exploited or called upon to work beyond the bounds of duty, before the YZF started drinking oil, like Oliver Reed consumed Jack Daniels. So that when the cursory compression test was undertaken, it revealed our worst fear, smack all to be honest, and a set of bores with more coke than we can find in a coke stoked oven.
We need to make some picture to explain this to the customer, seeing the inside of this Yamaha FZR now, ugly colors or not, it is going to be an expensive job we are sure that we have to completely rebuild the engine.
