[crashninja636]

I have an 03 636, great bike by the way. Has about 10000 miles, third set of Pirelli Dragons(awesome tires), full Muzzys stainless exhaust, stock everything else(no PCIII or other mods). My transmission went bad in third gear at about 4000 miles, bent shift fork and broken shift drum. Had lowsided it at about 80mph but it had been acting up in third prior to that. Dealer said it was the crash and I let it go at that($1500 out of pocket). After rebuild, the trans is a bit clunky, but still strong. Now I'm having engine cut off problems at about 9000rpm. It's worse in cooler weather, hot days it seems to be fine. It will rev past 9 if I pull in the clutch, but will just stutter if under a load. Does it in all gears at approx. the same engine speed (8500- 10000). Going to check ECU codes now, any help anyone can give?

 

[azaz]

had similiar problems with a R6 that I owned because the previous owner couldn't figure out what was wrong. Anyways my problem ended up being the carbs were out of sync, and that caused the slides not to open at the same time and the bike to stumble. If I just rolled the throttle on it would rev with load, but if I snapped the throttle it would stumble. Hope this helps.

 

[skywalker]

Originally posted by crashninja636
I have an 03 636, great bike by the way. Has about 10000 miles, third set of Pirelli Dragons(awesome tires), full Muzzys stainless exhaust, stock everything else(no PCIII or other mods). My transmission went bad in third gear at about 4000 miles, bent shift fork and broken shift drum. Had lowsided it at about 80mph but it had been acting up in third prior to that. Dealer said it was the crash and I let it go at that($1500 out of pocket). After rebuild, the trans is a bit clunky, but still strong. Now I'm having engine cut off problems at about 9000rpm. It's worse in cooler weather, hot days it seems to be fine. It will rev past 9 if I pull in the clutch, but will just stutter if under a load. Does it in all gears at approx. the same engine speed (8500- 10000). Going to check ECU codes now, any help anyone can give?

When you turn the key to the 'on' position, do you hear the secondary throttle bodies clicking and running their little calibration deal? They're designed to open only at higher RPM's to allow the engine to breathe better without sacrificing low-RPM torque...so if you don't hear them clicking, that's a sure sign, but either way it could be that they're just not opening, or not opening right, which could cause the bike to stumble since the fuel map is built assuming those valves will open at that RPM and give it more air. The only other thing I could think of is that it's an ECU glitch...fuel injectors and other mechanical parts wouldn't really cause the exact same result at the exact same RPM...it would usually have some varience to it.

 

[MadCow]

One way to find out if it's the secondary butterflies is when it's acting up unplug the wire going to the secondary butterflies, they should stay open & the FI light will come on.
If you do this throttle response will suck at low RPM's.

They have been experimenting with the secondary butterfly wire at Riderforums. http://www.riderforums.com/showthread.php?t=25665