Sudden loss of throttle under high acceleration

[beater_bimmer]

This is a bit hard to explain and I never spent much time investigating due to this happening both times upon entering the highway.

 

Bike is new and < 650 miles.

 

Twice now, upon firing up the bike after longer rides (1-2 hours running fine), under heavy accel onto the highway, I've lost throttle response (drops to idle) in gear (not in neutral).  I've then coasted to the shoulder pulling clutch in and tried to blip throttle - no response after several attempts. Seems like a false neutral?

 

After this, I've hit the kill switch and restarted and things have been fine. Since this has happened, it's left we pretty confused.

 

Next time this happens, I hope I can have more time to investigate the cause/symptoms safely and more thoroughly.

 

Has anyone experienced anything like this?

[beater_bimmer]

Mystery solved!

 

This happened again on me and I took the time to figure it out before moving on! @DORTx2was correct!

 

I had recently installed Koso heated grips and did not use glue when installing as it was a super snug fit and glue is messy. BUT when the grips heat up, the fit is less snug so it would allow the grip to spin around the throttle tube "freely" and make it appear like I had a loss of throttle.  I'm glad it's a simple fix.  I'm going to be gluing or safety wiring my grips this weekend.

 

Thanks for all the tips and ideas y'all!

[AZJW]

No experience with this, but checking if your ECU has recorded a trouble code might help diagnose this.  I have this adapter and a Bosch OBD scanner, but many different models are available on Amazon from around $30 and up. 

 

https://www.amazon.com/Diagnostic-Adapter-Connector-Motorcycle-Scanner/dp/B088TLYHQT

 

 

[Liquidape]

5 hours ago, beater_bimmer said:

This is a bit hard to explain and I never spent much time investigating due to this happening both times upon entering the highway.

 

Bike is new and < 650 miles.

 

Twice now, upon firing up the bike after longer rides (1-2 hours running fine), under heavy accel onto the highway, I've lost throttle response (drops to idle) in gear (not in neutral).  I've then coasted to the shoulder pulling clutch in and tried to blip throttle - no response after several attempts. Seems like a false neutral?

 

After this, I've hit the kill switch and restarted and things have been fine. Since this has happened, it's left we pretty confused.

 

Next time this happens, I hope I can have more time to investigate the cause/symptoms safely and more thoroughly.

 

Has anyone experienced anything like this?

No have not and I do fairly long uninterrupted rides.  I would be talking to the dealer and at a minimum asking the to check the stored codes.  What you are describing is not typical and frankly should not happen. 

[DORTx2]

I'm not sure if it would be the same problem but I had an issue similar to this, my throttle grip didn't have glue on it and it was sliding loose of the actual throttle tube. It would only happen on hard accelerations.

[Firebolter]

check the kickstand sensor switch, if it is faulting, it can cause symptoms like that-

[Canzvt]

So, since this bike is NOT a ride by wire engine, the most likely candidate for your issue is mechanical in nature as there is a physical connection from your right hand to the throttle plates. Dropping the kickstand (or a faulty switch) while in gear will kill the engine.

 

Try this to diagnose: With the engine off, and standing on the left side of the bike (ideally on a center stand, but not necessary) look at the throttle cable pulley just under the tank (see pic) while rotating the throttle grip. Does the pulley move? Try holding the pulley stable and twisting the throttle grip? Is there a bunch of resistance from either? If that is all OK, it might be time to check for codes.

[Liquidape]

Thinking about this more and going off the fact you mention it only happens at full throttle, my first guess would be the throttle position sensor is throwing an out of range number to the ECU and it’s kicking into limp mode until you restart the bike. 

The bike is not ride by wire but there is a sensor that tells the ECU how open the throttle plate is. 
if it was out of warranty that’s where I would start. But since it’s in warranty, I would make it the dealers problem. 

[dubdub]

On 3/22/2021 at 4:50 AM, DORTx2 said:

I'm not sure if it would be the same problem but I had an issue similar to this, my throttle grip didn't have glue on it and it was sliding loose of the actual throttle tube. It would only happen on hard accelerations.

: I would also suggest to get the dealer to check the glue on the throttle grip. I had the same issue on mine and the dealer told me its a fairly common occurrence.

[gone2seed]

 Not throwing up any codes?

My guess would be a loose connection between the ECU and the TPS or CPS. 
  If it was mine I would unplug the connectors, spray ‘um out with electrical contact cleaner, apply dielectric grease to the seals, and make sure they are put together tight.

  Worst case scenario, 6 years ago a momma mouse made a nest under the seat of a wrr. Da bitch chewed through 4 or five of the ecu wires and ate the insulation off half a dozen others. When I pulled the seat she took her brood down into the air filter and made me fish them out with a hooked probe. 

  Hate rodents!

[DORTx2]

30 minutes ago, beater_bimmer said:

Mystery solved!

 

This happened again on me and I took the time to figure it out before moving on! @DORTx2was correct!

 

I had recently installed Koso heated grips and did not use glue when installing as it was a super snug fit and glue is messy. BUT when the grips heat up, the fit is less snug so it would allow the grip to spin around the throttle tube "freely" and make it appear like I had a loss of throttle.  I'm glad it's a simple fix.  I'm going to be gluing or safety wiring my grips this weekend.

 

Thanks for all the tips and ideas y'all!

I think thats the first time I've been right about anything.

[NvNick]

Every heated grip i have installed required epoxy instead of glue. The heat from the grips can and will release the glue.