I had my MC21 sp at the track last weekend and something funny was happening. 1st and 2nd gear revved all the way to red line but every other gear struggled, nay refused to pass 9,000 rpm.

What could cause this? I was thinking it could be RC valves or spark plugs? But I’m just a weekend mechanic that tinkers on my own bikes. Any help would be greatly appreciated.

Thank you in advance,

Markus