Pulsing/jerking around 4k rpm?

[B4zs1.]

Hello guys!

I have a problem, when I ride at city speeds (in second gear at around 50-55 km/h, with a stable 4000 RPM), the engine gives a pulsing feeling, as if I were momentarily letting off the throttle. It could even be described as jerking. The bike responds well to throttle input, accelerates well, and everything else seems fine, but I can’t figure out what the issue might be. I simply have no idea what’s causing it. By the way, the engine was manufactured in 2007. The bike is completely stock, except for an Akrapovic exhaust and the exup valve is disabled.

I’ve read through many forums, and quite a few people have a similar problem, but I haven’t found a solution. Could a fuel cut eliminator help?

Has anyone else experienced a similar problem? Does anyone have a suggestion for a solution? This issue is simply annoying.

-New chain and sprockets are installed
-New tires are installed, and the wheels are balanced
-Valve clearances are set to factory specifications
-Timing chain is also in perfect condition
-It has been tested with new ignition coils as well. (All 8 have been tested for primary and secondary resistance, and they were all perfect)

 

[cannedSardina]

Hello guys!

I have a problem, when I ride at city speeds (in second gear at around 50-55 km/h, with a stable 4000 RPM), the engine gives a pulsing feeling, as if I were momentarily letting off the throttle. It could even be described as jerking. The bike responds well to throttle input, accelerates well, and everything else seems fine, but I can’t figure out what the issue might be. I simply have no idea what’s causing it. By the way, the engine was manufactured in 2007. The bike is completely stock, except for an Akrapovic exhaust and the exup valve is disabled.

I’ve read through many forums, and quite a few people have a similar problem, but I haven’t found a solution. Could a fuel cut eliminator help?

Has anyone else experienced a similar problem? Does anyone have a suggestion for a solution? This issue is simply annoying.

-New chain and sprockets are installed
-New tires are installed, and the wheels are balanced
-Valve clearances are set to factory specifications
-Timing chain is also in perfect condition

The first thing I thought of was a misfire due to ignition coil failure….lots have had that. You must pull the coils and test em, or just get new ones like I did. It was time. Sometimes people find that water infiltrated the spark plug hole. I’d replace plugs too.

To be clear the engine is not running smooth? Feel like throttle cutting out.

You said “stable 4000rpm” somewhat ambiguous.

 

[B4zs1.]

The first thing I thought of was a misfire due to ignition coil failure….lots have had that. You must pull the coils and test em, or just get new ones like I did. It was time. Sometimes people find that water infiltrated the spark plug hole. I’d replace plugs too.

To be clear the engine is not running smooth? Feel like throttle cutting out.

You said “stable 4000rpm” somewhat ambiguous.

I’ve edited the post because I forgot to mention that it was tested with 4 new ignition coils, and the primary and secondary resistance of all 8 has also been measured and they’re flawless. I’m certain this isn’t the issue. I’m feeling slight jerks, a pulsing sensation, as if the chain were intermittently stretched (the old one was like that, and I thought replacing it would solve the problem), but now everything is new, and the issue still persists.

 

[moosecapades]

Hello guys!

I have a problem, when I ride at city speeds (in second gear at around 50-55 km/h, with a stable 4000 RPM), the engine gives a pulsing feeling, as if I were momentarily letting off the throttle. It could even be described as jerking. The bike responds well to throttle input, accelerates well, and everything else seems fine, but I can’t figure out what the issue might be. I simply have no idea what’s causing it. By the way, the engine was manufactured in 2007. The bike is completely stock, except for an Akrapovic exhaust and the exup valve is disabled.

I’ve read through many forums, and quite a few people have a similar problem, but I haven’t found a solution. Could a fuel cut eliminator help?

Has anyone else experienced a similar problem? Does anyone have a suggestion for a solution? This issue is simply annoying.

-New chain and sprockets are installed
-New tires are installed, and the wheels are balanced
-Valve clearances are set to factory specifications
-Timing chain is also in perfect condition
-It has been tested with new ignition coils as well. (All 8 have been tested for primary and secondary resistance, and they were all perfect)

Gen II came with spark retarded below 4-5K rpm yo keep old men like me from getting looped out of the hole (or meet smog).
FCE is old tech, a d really just a band aid. You need an ECU flash. Vcyclenut and Ivan both do flashes. I have Vcyclenut flash ($200) you just need to fill out a questionaire with mods, etc. Transformed my '09 into a beast. Just search for vcycllenut. Dave Verdeccia is the owner and a great guy to work with. When you get it done be careful on your first gew miles, because the bike

 

[jwarden]

Gen II came with spark retarded below 4-5K rpm yo keep old men like me from getting looped out of the hole (or meet smog).
FCE is old tech, a d really just a band aid. You need an ECU flash. Vcyclenut and Ivan both do flashes. I have Vcyclenut flash ($200) you just need to fill out a questionaire with mods, etc. Transformed my '09 into a beast. Just search for vcycllenut. Dave Verdeccia is the owner and a great guy to work with. When you get it done be careful on your first gew miles, because the bike

Sounds like it is not running correctly. My 09 is very smooth in 2nd gear as low as 3000 rpm without a flashed ECU. Might want to get a flash for other reasons but it seems that there is currently a problem with the bike that should be fixed.

 

[moosecapades]

Sounds like it is not running correctly. My 09 is very smooth in 2nd gear as low as 3000 rpm without a flashed ECU. Might want to get a flash for other reasons but it seems that there is currently a problem with the bike that should be fixed.

THERE IS FACTORY IGNITION RETARD BELOW 4K.
IF YPU HOVER THERE IT WILL GO FROM RETARD TO NORMAL HUNTING BACK AND FORTH.
THE ONLY WAY TO FIX IT IS AN ECU FLASH GENIUS!