[BuilderBob*01]

Recently rebuilt the carbs on my 1998 1500 Goldwing. Bike starts great, idles great (900 RPM), etc.

However, after warming up, I've noticed a cylinder not firing. I can hear this in the exhaust; sounds like the right side when sitting on the bike.

I've checked for vacuum line leaks, vacuum lines on the carbs correctly, etc. Have found nothing.

When accelerating from a stop, I notice a cylinder miss until about 2000 RPM; then the cylinder comes in and the bike runs strong.

Any ideas where I should be looking...appreciate any feed back
BuilderBob

 

[Bryanlj]

Plug or plug cap i would think, or compression down on 1 pot

 

[redwing52]

Recently rebuilt the carbs on my 1998 1500 Goldwing. Bike starts great, idles great (900 RPM), etc.

However, after warming up, I've noticed a cylinder not firing. I can hear this in the exhaust; sounds like the right side when sitting on the bike.

I've checked for vacuum line leaks, vacuum lines on the carbs correctly, etc. Have found nothing.

When accelerating from a stop, I notice a cylinder miss until about 2000 RPM; then the cylinder comes in and the bike runs strong.

Any ideas where I should be looking...appreciate any feed back
BuilderBob

I assume the misfire was not there before the carb work?
Could put a tach on it and remove each plug wire one at a time but be sure you short the unplugged wire to ground.

By checking the tach you can find the cylinder that is acting up. Then check what Bryan suggested.

It is possible you have an issue with the low speed (idle) circuit in the carbs.
The other cylinders can tolerate thee problem but for some reason one cylinder doesn't like it.

Lot of possible variables why just one would act up?

Another thing you can do is unplug the fuel pump with the engine running and see if the engine goes smooth when the fuel gets low.
If so it is likely rich at idle.
If that is not the case, a spritz of gas in the air box will tell you if it is lean.

Have you adjusted the mixture screws?
Should be done at 750 RPM or lower.

 

[Pure Texas]

Since one carb feeds 3 cylinders then doesn’t make sense one of the three cylinders would have an issue with misfiring on one cylinder?

 

[DriverRider]

Recently rebuilt the carbs on my 1998 1500 Goldwing. Bike starts great, idles great (900 RPM), etc.
When accelerating from a stop, I notice a cylinder miss until about 2000 RPM; then the cylinder comes in and the bike runs strong.
Any ideas where I should be looking...appreciate any feed back
BuilderBob

Unless you have confirmed it is only one cylinder missing the likely cause of the engine problem which straightens out at 2000 RPM is a lean running condition of one carburetor. When you get going past that 2K RPM the main and secondary mains are in play and that drowns out your lean idle mixture. I would bet that when opening throttle very slowly then holding with machine stationary it surges at around 1200 RPM.
What all did your rebuild job include?

 

[BuilderBob*01]

Unless you have confirmed it is only one cylinder missing the likely cause of the engine problem which straightens out at 2000 RPM is a lean running condition of one carburetor. When you get going past that 2K RPM the main and secondary mains are in play and that drowns out your lean idle mixture. I would bet that when opening throttle very slowly then holding with machine stationary it surges at around 1200 RPM.
What all did your rebuild job include?

Thanks for the thought and great suggestion. It is only one cylinder. With my work schedule, I'm not going to be able to try the various suggestions until this Saturday. When I do I'll let everyone know what I found. Your input is very much appreciated.

BuilderBob

 

[BuilderBob*01]

Plug or plug cap i would think, or compression down on 1 pot

Will do some checking this weekend when off work. Thank you so much...

BuilderBob

 

[BuilderBob*01]

Unless you have confirmed it is only one cylinder missing the likely cause of the engine problem which straightens out at 2000 RPM is a lean running condition of one carburetor. When you get going past that 2K RPM the main and secondary mains are in play and that drowns out your lean idle mixture. I would bet that when opening throttle very slowly then holding with machine stationary it surges at around 1200 RPM.
What all did your rebuild job include?

Will certainly look into this. I'll check things more closely when off work this weekend.

BuilderBob

 

[BuilderBob*01]

Unless you have confirmed it is only one cylinder missing the likely cause of the engine problem which straightens out at 2000 RPM is a lean running condition of one carburetor. When you get going past that 2K RPM the main and secondary mains are in play and that drowns out your lean idle mixture. I would bet that when opening throttle very slowly then holding with machine stationary it surges at around 1200 RPM.
What all did your rebuild job include?

Will take a closer look at this problem when off work this weekend. Thanks for your input...

BuilderBob

 

[BuilderBob*01]

Since one carb feeds 3 cylinders then doesn’t make sense one of the three cylinders would have an issue with misfiring on one cylinder?

I believe your right. I'm leaning towards a bad plug wire.

BuilderBob

 

[BuilderBob*01]

I assume the misfire was not there before the carb work?
Could put a tach on it and remove each plug wire one at a time but be sure you short the unplugged wire to ground.

By checking the tach you can find the cylinder that is acting up. Then check what Bryan suggested.

It is possible you have an issue with the low speed (idle) circuit in the carbs.
The other cylinders can tolerate thee problem but for some reason one cylinder doesn't like it.

Lot of possible variables why just one would act up?

Another thing you can do is unplug the fuel pump with the engine running and see if the engine goes smooth when the fuel gets low.
If so it is likely rich at idle.
If that is not the case, a spritz of gas in the air box will tell you if it is lean.

Have you adjusted the mixture screws?
Should be done at 750 RPM or lower.

Thanks...I'm leaning towards a bad plug or plug wire. I'll let you know what I find this weekend.

BuilderBob