Restoring a Crashed Yamaha YZF-R1 2003
We're also not going to try to build a better bike than Yamaha engineers, who spend their careers welding and working on CAD-CAM machines, I can only dream off. We know our limits, at least when it comes to welding.So, yes, more horsepower might be nice, but we're interested in boosting midrange and sweetening the handling. Before we start changing things more radically, we need to see what we've got.
We found after an afternoon on the dyno that the Yamaha R1, without any of the corrections that can make a bhp figure a little more optimistic; so it are real-world back wheel numbers. We got 136bhp at 11,126rpm isn't brilliant, we know, but it isn't bad, and we're kind of thinking the real deal with this bike will be getting the most useful power, rather than the highest top-end numbers. That's why we've already lowered the gearing to make the power to the back wheel more accessible.
The standard Yamaha R1 are geared way higher than necessary, so lowering the gearing, in our case, one tooth down on the front and two up on the rear sprockets, gives the engine more chance of delivering all the power it can within a useful part of the rev range.
These power specs might be closer to what you'd expect from a tuned, correct Suzuki GSX-R750 than a 2006 Yamaha R1 sportsbike which illustrates how engine development has moved on significantly since 2003. Mind you, even back then the Yamaha R1 was lagging behind the Suzuki GSX-R1000 of the day.
But we're thinking the important thing with our bike is to the perfect roadbike without blowing insane amounts of money on major engine surgery. All the horsepower in the world won't improve road handling unless the bike will turn the corners and, importantly, get that power down through the rear tire without risking a higside every time we wind on the throttle. The handling of this Yamaha mode R1 is pretty sharp, maybe the sharpest Yamaha R1 of all. If we can make the most of that handling and improve the power delivery, as well as perhaps break the 140bhp mark.