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150f off idle bog/power up ?s

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Bought a 150 for my wife and after setting idle I found that it was elevated to compensate for an off idle bog. Adjusted air screw and no change. I'm gonna pull the carb and clean but want to replace jets while in there. Questions are

1. Has anyone experienced the bog and if so what fixed it?

2. What is the best jets for 600'? I'll open the airbox but most likely leave the exhaust baffle in depending on if my wife can tolerate the extra noise.

3. What is the procedure for setting float level?

 

TIA

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All the bikes with these round slides have a little bog if you crack the throttle fast enough. Simple  explanation is that they get a big gulp of air , the air outrunning the fuel. But it's more barometric pressure but same outcome. Usually we don't crack it like that in the real world. However, the bog can be excessive, a sign of incorrect jetting. I have a 150 but have never needed it to run better than it does so I am no help with the best jetting. However, someone from here will eventually offer up some help on that. I can't stand the noise of the baffle out, however I somewhat like the sound it has with a 1/2 hole drilled in the inner side end. More air flow, cooler sound, but not loud. The best way to set the float height is to forget about the manual specs, float tool, etc and use the clear hose method. A clear hose like sold as an oxygen fish tank hose from walmart will work. Route it as close to the bowl, shortest distance, from the bowl drain and up the side you see best while able to turn the bowl drain screw. Open the screw and watch the fuel come out and climb to the bowl to carb mating surface line, just below it, 1/16, below the gasket. No air bubbles can be present. If to high, or low, you will need to bend the tang on the float. It does not have to be exactly perfect. It will run fine higher or lower except that others jetting recommendations will be of no use since your not working from the same standard. Don't go higher than the gasket level. Two bogs... a rich and a lean. Usually it's lean with  too much air. Lean will almost stall out, rich will bog and recover. Both recover... hard to explain the difference. 

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The bog happens with almost any throttle applied at any rate at idle in neutral or with clutch disengaged but not when starting or in gear. Some times it will stall and others it will recover. Sounds like a rich bog

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OK, process of elimination. Use your choke in small increments to restrict air, trying it in several locations. Does it get better or worse? if better, then you have to much air, not enough fuel, a fuel blockage. If it gets worse, you don't have enough air meaning your rich

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Have you pulled the pilot jet out and inspected it? Can you see through it held up to the sun. Are the side holes, 4 or more open as well?

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17 hours ago, bfaucett said:

The bog happens with almost any throttle applied at any rate at idle in neutral or with clutch disengaged but not when starting or in gear. Some times it will stall and others it will recover. Sounds like a rich bog

If it were rich, when you snapped the throttle it would be at a better start point to not bog... The fast throttle opening creates a momentarily lean condition until engine RPM and vacuum rise enough to pull correct fuel through the needle or main circuit....

Any carb ... Round slide, flat slide, pumper or not... Can be opened fast enough to shut the engine off from a fast throttle twist... The most resistant to it would be a flat slide pumper carb that was tuned slightly rich off the bottom...

If anything it would be likely that you would need to be richer on all the circuits that come into play below 25% throttle opening...

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I guess it's lean then. From reading some other posts I think it might have an aftermarket air screw. I'm gonna order one along with jets and hopefully disassemble it in the next week or so. Don't have much free time unfortunately and issues with my bike take precedence

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