Leaning out carbs

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J.B.
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Re: Leaning out carbs

Post by J.B. »

DataRacer wrote:
JB wrote: Main Jet size will effect fuelling over the entire range, not just the top end.
That's just plain untrue. Pilot jet size affects the whole rev range, but you don't need to deviate from standard size (#35) for most road nc's.

Emto: If your a/f ratio is 11.5-12 at the top end then this suggests it is running a bit rich (12.5-13 is what you should be aiming for - depending on gear/load). I think you're on the right track trying 115/118 jets. Your engine could be down on power due to condition also.
I stand corrected, I was assuming the Pilot Jets are standard which they may not be. Also I was referring to the OP's question as to whether MJ size affects only the top end, which it doesn't. I must have missed something though - where did he post the a/f numbers you're referring to?
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royster81
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Re: Leaning out carbs

Post by royster81 »

JB wrote:
DataRacer wrote:
JB wrote: Main Jet size will effect fuelling over the entire range, not just the top end.
That's just plain untrue. Pilot jet size affects the whole rev range, but you don't need to deviate from standard size (#35) for most road nc's.

Emto: If your a/f ratio is 11.5-12 at the top end then this suggests it is running a bit rich (12.5-13 is what you should be aiming for - depending on gear/load). I think you're on the right track trying 115/118 jets. Your engine could be down on power due to condition also.
I stand corrected, I was assuming the Pilot Jets are standard which they may not be. Also I was referring to the OP's question as to whether MJ size affects only the top end, which it doesn't. I must have missed something though - where did he post the a/f numbers you're referring to?
he's not referring to any a/f number he's asking emto a question "if your a/f is 11.5-12.5 at the top"

emto,pop the carbs off and jot down all the settings. what jet sizes are used, how many turns are on the a/f screws, then come back and post them up. it sounds as though your dyno guy is a little lost with carbs and jets so it's possible he's set you bike up to run but not right.

and have you standard jets close to hand.
It's not having what you want but wanting what you've got....Loud ,Proud and Modified ....
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Re: Leaning out carbs

Post by emto »

Thanks Royster,

The A/F throughout the range is steady at 11.5. The pilot screws are set at 2.25 out. Shes running #35 pilots. The dyno guy did'nt touch the carbs, it was purely a power run.
I have a set of 115/118 jets so they will go in as soon as the weather improves along with the removal of the extra needle washers.

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