Took my bike out today and noticed that when I keep a constant throttle on her, the bike tends to jerk alittle bit, almost as if I was just running on fumes and she's starting to sputter. I took a look and there's plenty of fuel in the tank. Chain and tires all look good. I was thinking that maybe there's some water in the fuel...but I don't know what the symptoms are. Any help would be appreciated.

 

Also, this generally only happens when I'm running around 3000 rpm, and more noticeable at ~25-35 mph

 

I have the same issue on my 600rr and I am told that this is a stock fuel mapping issue.

I have downloaded stock the map from the PowerCommander site, and it shows that at around
10% throttle, the fueling just below 3000 rpm is higher than it is just above 3000 rpm. The same is true for my bike at 4000 rpm.

This means that if you are riding at 10% throttle, just below 3000 rpm, the bike may naturally speed up very slightly, and as the revs go above 3000 rpm, the gas is then limited a bit. For me, this means a jerky ride for a few seconds.

I am told that a PowerCommander will smooth this out, but I haven't gotten on yet. The more I ride the bike ( just over a year now) the more revs I use, so the time I spend at 4000 rpm is pretty small now.

To be sure, try a steady throttle at 5000 rpm or 4500 and make sure its behaving properly. I am told that Honda maps the engines this way to meet the emissions requirements. Not sure if thats true, or if they map more for power at higher revs.

Hope this helps,
Chris.

 

I had a similar problem and it was that my battery was dying. and I use to run 7000K headlights bulbs and it seems like it was sucking a lot of power and the bike was starving electricity to the ignition coils.

it happened below 5000rpms because our stator start producing power above 5000rpms. below that, you are just running on battery.

if that dont do it i would check the plugs.

 

Thanks guys. By tightening the negative terminal about a 1/4 turn, the sputtering issue is gone. Thankfully, it wasn't a bigger issue!