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Can tall gearing cause midrange jetting issues?

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Flywheel weights have always caused jetting issues for me, so I've always removed them from my 2 strokes. With the slide and needle open and the engine unable to rev up to accommodate, it floods and becomes rich as hell, and spooge city.

I'm wondering if the 14/47 sprocket combo, and the WR gears in the tranny of my YZ250 are causing the same thing. Midrange/low end bog on hills, but not much on flats where the engine is more free to rev.

Would one jet to accommodate the slower revving, or fix the slower revving/drag at its source? The top speed is nice for the open desert and flatter areas, but for 80% of the riding I'd rather have the throttle response, especially on hills.

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I think that gearing is way too tall for your 250. Your choking your engine. Yes it probably is causing your bog. If you want your snap back go back to stock gearing or close to it. Dont know if jetting would help.

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Your engine doesn't know what gear you are in, or what gearing you have.

It has no effect on your 'bog'.

If you start out in third gear with stock gearing, it will have no ability to pull until the rpm's are up to at least 4k.

Is that what you are talkling about? Because that's what 14/47 gearing is almost like with a stock YZ.

You have to be more specific: is the issue rpm related, or throttle opening related?

How old is your top end?

Have you done a leak-down test?

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Top end is brand new. <2 hrs on it.

I have not done a leak down test, but I suspect the wet side crank seal is leaking due to the excessive spooge and suspiciously small amount of oil coming out of the gearbox during oil changes.

RPM related or throttle opening related...I'd have to say it's more RPM related. Once the engine is up on the pipe it seems to do OK. But giving it a throttle whack from low RPM's, especially on a hill or some tight technical section, it obviously doesn't want to snap the front end up.

Thinking that the taller gearing "choke" on the engine, and the possibly leaking crank seal would explain the liquid diarrhea the bike seems to have on the silencer..

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