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Jetting 05 CRF150F BBR

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Bike = 2005 CRF150F.  BBR exhaust, air filter
Problem #1 - Cold Start, cannot start EVER with choke on.  Once started with choke 1/2-open or full-open it will barely purr and you must not use any throttle or it will stall.  Once idled for a while and bike warms up you can ride it as normal
Problem #2 (I believe directly related to #1) - Even with bike hot and running great, if you ever close the choke (full choke), the bike stalls, and then back to #1.  I realize you wouldn't ever need to do this, but I'd like to believe it should be possible.  On my CRF450R, it would simply result in higher RPM, bike running rich, etc.  Of course I don't do it.

Today I took the carb apart, pilot jet looked clogged (typical).  It was a 40, so I replaced it with a brand new 45 just for the fun of it.  BBR calls for 110/40 though, so hmm dunno.  I cleaned the main (was clear, but did it anyhow) too.   Drained the gas tank 100%, added a little bit more, drained it again, so it was damnnnnnn clean! Re-assembled the carb and re-attached afterwards.  Raised the throttle slightly since it did indeed seem a little on the low side even when hot.

Problems persist except that the bike seemed to want to start quicker than previously, but still it had to be done with the choke open, and still stalls (and subsequently will never start) with the choke closed.

I was thinking that when the butterfly valve is closed, air has to come in through those air pipes, right?  Perhaps those are clogged, would that cause this, even with a clear pilot?  The other idea is that it is just too rich with that pilot to start?  I doubt it.  It doesnt even WANT to start, it just kicks over and over and over and over and is almost as if the key was off (which it isnt).  Open the choke and then you can start it.

Any ideas?  Thanks

Edited by Agr0

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Ok for sea level at 70d average outside air temp that you ride in:
110 main, 42 pilot, needle clip in fourth slot from top (second from bottom)
Adjust idle mixture screw for highest idle speed then set base idle where you like it best.

Be easy on the kick starter.... the gears are known to break!

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My concern is that you can't start or run the bike EVER with the choke on, cold or hot.  Does that mean the air jets are clogged perhaps or air hole?

this pic is from a 230f I found online but still same idea..  choke plate 100% closed air has to come from somewhere right?



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