'10 RMK 800 mid-range stumble

[pj8556]

got a 800 RMK with '10 reflash and pciii box w/ SLPs map and exhaust.

the pciii is new and now i notice a very evident stumble, kind of on/off feeling around 5600-5800 rpms, when I add throttle around 5700 rpms it comes to life again, just seems like a dead spot, what can be causing this, i know slp's map richened up this RPM range.

also, per SLPs recommendation I recently added pink exhaust springs, could this be causing it??

not a big deal but kind of annoying on trail or in trees, power delivery used to be much smoother.

thanks for any advise

 

[crashnbash]

It could be your power valves opening. The ecu looks at tps, rpm, and pipe temp to decide when to close the solenoid to allow the valves to open. The rpm you said it happens at could be the point the ecu is closing the solenoid to open the valves.

 

[diamonddave]

I would try installing the stock springs back in.

Are you using the first 2010 map that came with the motor update or the Jan 2010 mid-season map?

What altitude do you ride? Are you running the SLP pipe and can>?

It should be ultra smooth. Surprised you found a "new" PC3.

 

[pj8556]

I ride 5000-7000 ft. That day i was mostly around 5-6k ft.

running SLPs pipe and can.

like i said the motor is running pretty strong and crisp it just wants to sometimes stumble and there is an on/off feeling right about 5600-5800 rpms