carb question

[mstic2000]

Just started noticing gradually after a few hundred miles this riding season that when I am cruising at a constant speed in any gear it sounds and feels like it isn't getting enough gas. It doesn't bog right down but it's noticable. If I give it some gas it goes right away but comes back when I stay at a constant speed. I changed the inline fuel filters and still the same problem. It starts right up cold and idles fine. Plugs? Dirty jets? vacuume advance? Thanks!

[dbeardslee]

Is the problem manifesting itself at a particular rpm level?

[mstic2000]

It doesn't seem to be so. Just at any constant speed. RPM's don't seem to matter.

[Rasputin]

I would be having a look at your pick up coil wires if you have not already done so. I started to have what sounds like a similar problem just weeks before I started having issues with them. Found the weak spot and it runs great again. JAT

[dbeardslee]

If it feels like it's starving for gas at a constant speed, it could be stuff in the fuel lines floating up to the filter, or to the screens on the fuel valves and obstructing them. Could also be a plugged gas tank vent. You can try cracking the filler cap open, and see if it still does it. If the problem goes away, clean the vent. If it doesn't I'd check the under side of the fuel valves. Also, how much gas did you have in the tank at the time?

[mstic2000]

Thanks for the suggestions. I checked the vent cap and that's not it. I'm going to check the coil wires next and the filters in the tank. I'll let you know if I find out what it is. Seems to do it if the tank is full of half empty. I haven't let it get down past half empty. But like I said it starts up fine hot or cold and idles just fine. I'm thinking probably in the coil wires is what it sound like.

[Crazcnuk]

I am wondering if what your are experiencing isn't just normal xs11...

These bikes don't really have a steady cruise spot. You are either accelerating, or decelerating all the time, although minimally, so what is happening is the bike is kind of 'jumping' back and forth between the two.

If you can give it throttle, when it is 'bogging' and it picks up and goes immediately, it can't be starving for fuel.

If it runs smooth the rest of the time, I doubt the p/u coils are at issue.

It might be being emphasized, more than normal, if your carbs are slightly out of synch or one of the idle mixture screws is out in relation to the others, so that you have one carb trying to go (or slow down) differently than the rest.

[mstic2000]

I went for a long ride this morning and it seems to do it only in the 2500-3000 rpm range. Any other rpms it's smooth. Haven't made the time to look at the coil wires and use a meter on them. It probably is time to sync the carbs again.

[tinman905]

I went for a long ride this morning and it seems to do it only in the 2500-3000 rpm range. Any other rpms it's smooth. Haven't made the time to look at the coil wires and use a meter on them. It probably is time to sync the carbs again.

Check your carb diaphragms you may have a few holes in them. Sometimes you can't see any holes until you hold them up to the sunlight or bright light.

[mstic2000]

I cleaned the plugs and it went away. It's back to running like a raped ape.

[randy]

I went for a long ride this morning and it seems to do it only in the 2500-3000 rpm range.

That's normal. The cams don't even wake up 'till 3500. The dirty plugs are an indication, too that you're running it too low in the rpm range. These motors like to breathe, give her some throttle.