I have a problem. I had a 98 YZ400 that I raced for 2 years. It was time for a new bike, and I didn't have to think twice about purchasing a new 426. I love everything about the bike except for the engine. It just doesn't seem to make as much power in the higher rpm's as the 400 did. I want to find out the easiest way to make it rev more like the 400 did. I rode my old 400 last night, and I definitely liked the power better. So if anyone has any suggestions, I would appreciate it. Thanks.