Throttle Inconsistency

[mbopp]

When holding a steady throttle, lets say 4th gear (but could be any) I get a sudden 'slow' when the bike acts as though I let off the throttle. And it is inconsistent. Fine for 10 seconds, off for 1, on for 5, off for 2, etc. There was a half tank of gas left over the winter, and I filled the rest of it up this spring, and that is where I'm at now. I plan to run some seafoam through it, but it seems as though it could be something else.

I cleaned the carbs last fall, and have not ridden it much since, though I don't remember this problem happening till this week / this spring.

I don't know if this is relevant or not, but I replaced the gaskets on the crank case this spring as well. And during the process I removed (and reassembled) the clutch basket when the head of bolt was broken and the bolt needed to be drilled out.

This is something that has probably already been discussed here on the forum, but my searching didn't reveal it.

[Dave8338]

Seafoam and run it. The gaskets that you replaced would have nothing to do with it. Also, the clutch work wouldn't effect things either (unless it went together wrong and was slipping...but you could tell that / RPM's up and speed down) :?

[Craiger]

Is there a fuel filter in the fuel line?

[mbopp]

No Fuel filter that I am aware of. I will go ahead with the seafoam and see what that does. It definitely isn't the clutch slipping, rather a lack of power, most likely from fuel.

[Craiger]

Definitely sounds fuel-related to me. I have a small in-line filter on the main fuel line between the tank and carbs. Might want to verify that you don't have one....as that "could" be your problem.

Definitely give the Seafoam a try and see what happens. Hopefully it'll take care of whatever's causing the issue.

[82Shafty]

Just make sure your throttle-hand grip is not slipping. I had that happen to me on my first bike.

If you're positive your grip is tight, the next time she bogs out on a run, add some choke into the mix before letting off the throttle to see if it corrects itself that way.

[mbopp]

I first thought that maybe the throttle grip was slipping but I've verified that to not be the problem. Where would the fuel filter be? Lodged in the middle of the fuel line somewhere? Or on one of the ends?

[Craiger]

In the fuel line between the tank and carbs. As the line isn't all that long, you'll see it if it's there. If it has one, it'll have two small clips holding it on.

[mbopp]

In the fuel line between the tank and carbs. As the line isn't all that long, you'll see it if it's there. If it has one, it'll have two small clips holding it on.

I guess I don't have one of those.

Thanks

[Craiger]

It's possible the gas sitting all winter without the bike running could be the issue. Just run the Seafoam through it and your problems will hopefully go away.

Just for kicks, how much have you ridden it this spring and how long was the engine running when you experienced this?

[mbopp]

I only have a couple of hours on it so far this spring. And it seems to happen throughout the ride. Up to 20 min. maybe. I only really notice it when I cruising at a constant speed.

[Eli69]

you may be running lean. do you have pods or aftermarket exhaust and haven't rejetted? does running with the choke on have any effect? or the carbs may have gotten gunked up a bit. is your tank clean?

i had a similar problem. had to clean carbs and gas tank several times.

[mbopp]

Everything is stock. The choke just keeps the rpms higher. Not sure how to determine if the gas in the tank is clean.

[chef1366]

Don't start worring till you run the old tank of gas through it. Still does it with new gas clean the carbs. Sounds like blockage in the pilot circuit.
Also make sure the petcock is good and you didn't kink the fuel line with the seat.

[mbopp]

What is a good way to check the petcock to see if it is working properly?