Let me clear this up. I used to own a 06 FZ1 naked, the bike uses the 04-06 5 valve R1 motor with a heavier crank and detuned. I brought the bike unseen and was very disappointed, i wont go into the specifics because there is a list long!!! but i had to spend about 2k on exhaust, gearing and fuelling just to make the thing perform similar to R1. The stock suspension is laughable, i ended up doing an R1 fork conversion with radial brakes, Ohlins rear shock and steering dampner as the FZ1 doesnt come with one. After spending the better part of 4-5k i had a sweet bike. In heinsight i should have streetfighted an R1 it would have been a hell of a lot cheaper!!!.Actually you are wrong. The current FZ1 does have 20 valves. I checked Yamaha's website to confirm it.