[Will_Estes]

After riding the bike for roughly 30-40 min on the highway, I got off the exit and stopped at a few stoplights. After the 3rd stoplight, I accelerated to roughly 50/60 mph. Once I hit 50/60, my bike started lose RPM and then they'd pick up again. Then after a few seconds it would do it again. After about a half mile of that, I had to turn so I slowed down/pulled the clutch, dropped into 1st, and then the bike stalled. I continued to hold the clutch in as the bike rolled slowly around the turn and then another 50 yards before I pulled off the road. Once the bike was stopped, I pressed the start button and it started up as if nothing was wrong. I rode it another quarter mile to my house with no issues.

 

[Dodsfall]

Did you check to make sure it's not low on gas?

Sent from my Z667G using Tapatalk

 

[Will_Estes]

Did you check to make sure it's not low on gas?

Sent from my Z667G using Tapatalk

Hello. Yes, I filled it up the night before and didn't do any riding in between. So gas level was not the issue.

 

[Dodsfall]

A couple quick things to try if it stalls again:

Tap the bowl of the carb with a plastic screwdriver handle a few times to hopefully dislodge a stuck float.

Open the gas cap and see if it will start right away. If it does, you may have a clogged vent for the tank.

 

[Will_Estes]

A couple quick things to try if it stalls again:

Tap the bowl of the carb with a plastic screwdriver handle a few times to hopefully dislodge a stuck float.

Open the gas cap and see if it will start right away. If it does, you may have a clogged vent for the tank.

Well, I can try those but both options require me to stop and pull over. At which point the bike turned back on easily. Are you trying to determine if the carbs need cleaned or the gas cap needs cleaned? I took apart the gas cap today and it didn't look dirty.

 

[WintrSol]

If the gas cap vent is blocked, the effect will happen less, if at all, as the tank empties, because it will take longer for the space above the fuel to begin to pull a vacuum strong enough to kill the bike, especially if you have a fuel pump. If the cap requires a key, use a spare key in it, so you can pop in open at the first sign of weakness.

 

[Dodsfall]

It could also be the float adjustment, or the fuel flow is being restricted.

It only happens during heavy fuel usage?

 

[Will_Estes]

If the gas cap vent is blocked, the effect will happen less, if at all, as the tank empties, because it will take longer for the space above the fuel to begin to pull a vacuum strong enough to kill the bike, especially if you have a fuel pump. If the cap requires a key, use a spare key in it, so you can pop in open at the first sign of weakness.

Hello. I took apart the gas cap and it didn't appear to be dirty. Granted, I'm new to this all so I may not know what I'm looking for, but after taking it apart I didn't see any buildup anywhere.

 

[Will_Estes]

It could also be the float adjustment, or the fuel flow is being restricted.

It only happens during heavy fuel usage?

Well I took the bike out last night and it seemed fine. I revved it pretty good in the lower gears, but I didn't ride it for the same 30-40 min (prob closer to 20)

I did notice a hint of RPM drop in top gear. Like if I was at 6K, it would drop to 5750 and go back up to 6K. It did that as I was accelerating but once I was cruising it seemed fine again.

Somebody else on another site suggested electrical, so I pulled the spark plugs out. Attached are the pics I took last night after my ride (Phones camera).

 

[Dodsfall]

It sounds like it is starving for fuel during high demand.

 

[Will_Estes]

It sounds like it is starving for fuel during high demand.

So what would be the proper steps to troubleshoot this? Also, I replied to your other post and edited with pics

 

[Dodsfall]

Those spark plugs look like it has been running very lean from the pictures. That would be more evidence to support starving for fuel.

As I mentioned above, the float level and fuel flow from the petcock would be the first things I would check.

 

[Dodsfall]

An small air leak could also cause these symptoms.

 

[Will_Estes]

Those spark plugs look like it has been running very lean from the pictures. That would be more evidence to support starving for fuel.

As I mentioned above, the float level and fuel flow from the petcock would be the first things I would check.

Ok, I will try to take a look at this today. I will also change the spark plugs just for peace of mind that it's not them.

 

[Will_Estes]

An small air leak could also cause these symptoms.

Would this need a mechanic to determine?

 

[WintrSol]

If you have a propane torch, you can use it to check for an air leak. Turn the gas on (don't light it!), and aim it around the intake boots and any other areas that may leak air, like the throttle arms, and, if the idle changes, you've found a leak. Make sure you don't have any leaking sparks - you don't want the propane to light. Some folks use a focused spray of WD-40 instead of propane; never tried it myself.

If you have a manual, it should provide the fuel levels; mine has instructions for measuring the levels with the carbs on, using a clear, U-shaped tube connected to the drain. When the drain is opened, the fuel rises in the tube, and you measure the height relative to the reference on the carb. The petcock is in the open position (prime if you have a vacuum-operated petcock) for this test.

 

[Dodsfall]

Brake cleaner or carb cleaner is also good for testing leaks around the carb boots or vacuum lines.

 

[Dodsfall]

I would replace the plugs. They look like they are getting pretty old.

 

[Will_Estes]

I would replace the plugs. They look like they are getting pretty old.

Replaced them. Didn't make any difference as it still stalled

 

[Will_Estes]

Brake cleaner or carb cleaner is also good for testing leaks around the carb boots or vacuum lines.

I'm not very mechanically inclined, so I may end up taking it somewhere for this :frown: