Jetting after M-Tech

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nellyboyo
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Just fitted an M-tech and am happy with it after a bit of fettling to the stator .
My question is why does it affect the slow running jetting so much . I had to go down a size on my PWK pilot jet to get the mixture screw to have any effect at all ?
I`m not the brightest about the in depth technicalities of how timing affects jetting ? :?
I went up a main jet one size and down a pilot jet one.
Just like to understand it really
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coaster
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Probably would depend on which ignition curve you selected, some retard a little, then advance a lot and then retard a lot. That is bound to affect the way that the fuel is burnt at different points in the rev range.
nellyboyo
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It retards now from 23 all the way down to 16 now . Setting number 8 on the box .
So it burns less fuel as its more advanced ...or at least burns it more efficiently and therefore requires less. ? Is that right ?
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drunkmunkey6969
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Generally speaking, you'd fuel the advance.


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nellyboyo
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So I`d seem to have gone a bit arse backwards by a small amount.
I've definitely gone too rich lower down . The dropping of the pilot one size has brought the mixture screw back into range after a turn and it seems fine so I`ll leave it a that and keep plug chopping . tidy ;)
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