Stumbling/power loss under load
Hey, everybody. Bought a 2001 VN750 in May and I'm loving it (except for the seat!).
It's giving me trouble under high load in higher gears and at mid to higher rpm. It tends to stumble a bit and lose power. If I keep the throttle wide open, it just keeps up with the stumbling and less than expected acceleration. It doesn't stumble and then recover, like it might with a temporary lean condition.
It runs just fine as long as I avoid high load (wide throttle) at mid to high RPMs in the upper gears. No problems starting, hot or cold, and no problems idling, and no problems with how it feels or with power at lower RPM at partial throttle. In fact, in my daily commute, I generally never experience the problem unless I intentionally go out of my way to test it.
I'm getting 50 MPG on my daily commute, which is 35-50 mph for 17 miles each way.
On our first road trip recently, with a pretty good load and two up, it was hard to even keep 40 mpg, being generally high 30's unless I really kept the speed down (below 60 mph). On one tank, at around 75-80 mph, I didn't even get 30, but there was a lot of wind.
The plugs look OK, being generally brownish, with no sign of running rich or lean.
Any ideas on where to start looking?