Bike bogs down after jumps

[mainline]

Vandy suggested the splash guard around the mainjet may be missing but it's not. Any suggestions?

[vandy010]

just throw me in the deep end wouldya!
over rough terrain, when given a handfull of throttle after backing off is where i noticed it most.
on Pauls mighty PE175 this is.
i thought it may be missing the splash guard around the mainjet but Mainy reckons it's there.
just wondering if the pilot may be too rich.
it runs real good otherwise and this is only an intermittent problem.
am i right Paul?

[Stan S]

Vandy suggested the splash guard around the mainjet may be missing but it's not. Any suggestions?

I would go for needle and seat or float height or both.

Stan.

[Lozza]

I say float height, depends if it's rich or lean bog too....................

[mainline]

It felt like a rich bog. If you get my drift.

[vandy010]

It felt like a rich bog. If you get my drift.

you mean like,
after curry..

[BJJ]

agree with Lozza and Stan

[mainline]

you mean like,
after curry..

No, more like the one that killed Elvis.


So if the float level is a possible cause I'm assuming I need to lower it?

Cheers guys.

[Stan S]

Well yes you may need to lower your fuel level depending on the specs for your model carby. But beware it may be caused by the needle and seat not shutting the fuel off completely and allowing the fuel to bleed in and raise the fuel level.

Regards Stan.

[mainline]

Is there a way to check if the needle and seat are sealing?

[evo550]

Excuse my ignorance, but what's a "rich" bog and how do you tell the difference between it and a "lean" bog?
I thought all bogging down from jumps was a leaning of the air/fuel mixture.
As the bike comes back down to earth the fuel in the bowl gets suspended in the air (lifts up of the bottom of the bowl), if the float level is set too low then the main jet becomes exposed to the air and is starved of fuel for fraction of a second before the fuel drops back down in the bowel and again supplies the jet with fuel.
If this is the case then you need to raise the float level to ensure a constant fuel supply to the engine.
At least I think that's how it works.

[Lozza]

I would say that the floats themselves are more likely to be affected rather than the fuel. As they are actualy lighter than the fuel.The rich/lean bog is just a stutter or hesitation when you crack open the throttle,same as rich or lean any other time.
I no fuel goes in my bowel

[DR]

usually find RM's and PE's run pretty high float levels for this very reason. Not unusual for fuel to piss out the vent pipes if the bikes is merely leant at a slight angle against the odd trailer/car/tree/rock/stick/post/cow or any other alternative resting device we conjure up. I'd up the float level and drop the clip a notch and see where that heads..maybe south but at least you'll eliminate excess/lack of fuel scenario if it does little or nothing   safer than going leaner if it's running well otherwise. I presume the airbox doesn't have the top cover fitted?

[mainline]

No, the airbox cover is still on?

[vandy010]

get rid of the airbox cover.