Jetting question.

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jasonp

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When you have your bike at full throttle just about top rpm and you let off to about 1/2 I'm getting a hesitation. Like the bike will die for a second and then pick back up. Almost like you shut the engine off or the kill switch then returns back to being fine. From the tuning manual it states that if the bike stutters when shutting down the throttle from 3/4 to 1/2 then lower the needle as the bike is running rich. Has any body found that to be true?
I'll have to try it out but last time I try to lower the needle it ran to lean, bogged and when I raised found the mixture was just to rich and wouldn't rev up to full throttle. I wonder if the accelerator pump timing is just a little to much.
 
That was with the old .390 cam. Finding this .450 a little harder to turn and doesn't run as smooth.
I think to I'm still just a hair lean on the main as I'm feeling the bike pull really hard then in the mid range start to get soft and then start to pick back up again and pull really hard. Never ending it feels like. But still fun to get the results as it really makes the engine run great and have a lot of power.
 
If its bogging, then its a bit on the rich side. If its stuttering, its lean.

Bogging is a subtle hesitation like its gotta wind-up a little 1st before it takes off.

Stuttering is like a hesitate-go-hesitate-go (kind of like coughing) before it takes off.

Hope that makes sense!

Which description fits the best Jason?
 
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