Help! Poor running and I want to go to Sturgis

BeastMaster

.040 Over
Joined
Jan 14, 2019
Messages
99
Location
Ogden Utah
Ride
2012 rocket III roadster & 1995 Magna
So it is two days before I got to leave for Sturgis. And 2012 my rocket 3 roadster. Is giving me fits. It stumbles at around 2,000 rpms when not under load and hot. I've tried testing the idle control stepper. Cleaning the linkage. It has gotten better but still stumblingly some. Any help would be much appreciated.
 
Before messing with that screw, I'd try other things. Obviously the screw was set right for 8 years. I'd start with the TPS.
I checked it today, but I'll definitely check it again. Can't be too sure. Thanks!
 
Before messing with that screw, I'd try other things. Obviously the screw was set right for 8 years. I'd start with the TPS.

Disconnect the motor to see if your idle problem resolves. If the idle without the stepper motor is too low keep the motor running with the throttle. Go ride the bike. Plug it back in to see if the problem comes back. The stepper is just a computer operated servo to control the idle. The motor goes bad and the linkages get dirty and gum up with lubing gue. My bike and several others here work just fine without it.

Aaahhhh and order a TPS, assuming you are familiar with Tune ECU.
 
Disconnect the motor to see if your idle problem resolves. If the idle without the stepper motor is too low keep the motor running with the throttle. Go ride the bike. Plug it back in to see if the problem comes back. The stepper is just a computer operated servo to control the idle. The motor goes bad and the linkages get dirty and gum up with lubing gue. My bike and several others here work just fine without it.

Aaahhhh and order a TPS, assuming you are familiar with Tune ECU.
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Yeah I messed with the idle stop yesterday because my idle would drop. Today it didn't like it so I'm going to try and match the idles closer. It turns out the rough spot is at about 1000rpmnot 2000 my dab. I'm hoping this solves it. I have tune ECU and I'm ordering a tps tomorrow. Hopefully they have one in stock. This sucks cause just don't have the time. Thanks 1k9
 
I checked it today, but I'll definitely check it again. Can't be too sure. Thanks!
Ok my two cents even though there is a shortage. Work with me here . It stumbles criusing down the highway at about 2000 rpms. Hmm not sure but that does not sound like a idle problem. I mean you criusing down the highway at 2000 rpms not idling. And in you first post you said you tested the stepper motor clean and lubricated the spring and linkages and noticed a positive change hmmmm. I must ask do you have a lot of mileage at about 2000 rpms or is it fairly low mileage?
 
Ok my two cents even though there is a shortage. Work with me here . It stumbles criusing down the highway at about 2000 rpms. Hmm not sure but that does not sound like a idle problem. I mean you criusing down the highway at 2000 rpms not idling. And in you first post you said you tested the stepper motor clean and lubricated the spring and linkages and noticed a positive change hmmmm. I must ask do you have a lot of mileage at about 2000 rpms or is it fairly low mileage?
Actually I was wrong it's at 900-1000rpm. Sorry in a major rush between work and everything. I have just under 30k miles on it. I typically cuise about 2300+ rpm the engine/mileage seams to like it there.
 
Ok that changes things except for the part that you cleaned and lubricated it and there was a positive change. If it were myself I would clean and lubricate it more . Paying special attention to the springs in the front as they have to do with idle , the idle stepper motor cam tension and proper operations
If the spring returns aren't working right the stepper motor has problems adjusting the proper opening. Note the area in the box and what the arrow is pointing at.
idle movment 1.jpg

Then I would also lubricate the stepper motor using the idle stepper mot test to nove the motor shaft in and out. Do the test several times after lubricating like below
20190515_140225.jpg


Then check the proper freeplay in each throttle cable so its not fighting each other and the stepper motor.
20170701_152914.jpg


Once I did that I'd run a full ISCV reset along with resetting the adaptations after the reset is done. Then cycle key off and count to 5 then turn it on and start the bike without moving the throttle. Run it until the fan kicks on then run it for 12 minutes more without touching the throttle. Now while its doing this you here it change the rpm. As its adjusting it on fuel idle and its off fuel idle sequences. While its idling I'd be taking note of vacuum numbers on each throttle body looking for leaks then see how and if they are in balance. Like I said if it were me!!!
 
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