Originally posted by Pyrus
The bike has performed perfectly for me for the 4 years I've owned it now...... Halfway up the hill without warning the power cuts on me.
That doesn't sound like a burnt valve. They tend to go gradually because they don't burn all at once. I thought the engine in them was the same as the CBR-1000 and if so, they're not hydraulic lifters but screw adjusters. I have 55,000 miles on a CBR-1000 that I run the wheels off of regularly and the only thing I've done to it beyond regular maintenance and valve adjustment every 15,000 miles or so, is a cam chain and tensioner this past winter at 52,000. The symptoms there were not performance related but a little chain rattle when cold that quieted down after about a minute running. I would get a second opinion and look at carb diaphragms, dirty gas screen above the petcock, water in the gas, plugged tank vent, and things like that. If they are mechanical adjusters, check adjustment too, and if any are tight... then maybe you do need a valve job.
One word of caution when doing a compression check. The throttles should be open when turning the engine over. This is recommended any time you use a compression gauge but is not often done on cars to no real problem because they all draw from a common manifold with one set of butterflies. This affords a large reservoir of air to draw from and being common to all cylinders, still accurately detects disceptancies between cylinders. On a motorcycle, the very short intake runners and the fact that they have individual butterflies means you get a less than full fill of the cylinder with the butterflies closed causing your readings to be lower than actual, but worse yet, they are likely to be erratic from slight variations in carb sync. This will indicate trouble that may not be there. Make sure the compression check was done with the throttle open.
Another thought... I know you said a compression check was done but if someone made this call from spark plug coloration, remember that 1-3 and 2-4 are common to the ignition coils and ignition system. It could be coincidence but it makes me say hmmmm. Hope that helps. I'd get another opinion from a good independent. You must have some of those around your area. Maybe Hammer or somebody out there could recommend one. Hope that helps.
BTW, I'll ask around a little here and see if someone can confirm whether or not that has hydraulics, or are you sure of that yourself?
Edit add: If they are mechanical adjusters and you've never adjusted them, start there. I re-read your description and that sounds like it could be tight valves, too. If you do have any tight ones, they may seal up with adjustment but may burn in the near future from damage started by running tight.