I was out riding last week and I had motor problems. The motor would idle for a minute then load up. This was not a big concern because it would clean up when you started off again. The big problem came when I would hold throttle at 3/4 for a while then it would feel like I have a fouled plug (not the case). Let up then it was fine. New plugs but no different. A day later it was now at 3/4 and full throttle or any speed that I would hold a while (1-2 minutes). It seemed like there was a stutter box or a rev limiter on. Anyone else had this problem?