'98 Tiger jerky acceleration - please help !

[Mustang]

raising the needles may do the trick.

that is the change that will take out the bog in the midrange

a 98 main jet has a hole in it that is .0386 thousandths of an inch in diameter

98=.0386 inch
100 = .0393
102 = .0401
105 =  .0413

my keihins with 105 mains get anywhere from 42-55 miles per US gallon depending how it is ridden

[Mustang]

From 98 stock to 105 is a very big jump IMHO without air filter or exhaust mods.   With a K&N filter, that is a different story.

box stock exhausts and air filter love's the 105's ..must be the NH weather

I know half sizes exist but that does not mean that every half size (or even whole number size) is available.  If my mains are 98, I cannot get a 98.5......unless I drill it myself.

you won't see half sizes until you get into much bigger main jets ........there isn't enuff difference in size in the smaller sizes to bother with half sizes that is also the very same reason that mains down around the 100 size can easily take two ,three even 5 size jumps without really being too drastic of a change

ie a 98 is a .0386 hole a 98.5 would only be .0001 bigger diameter

but a 180 main would be  .0708 and a 180.5 would be .002 difference in diameter

it aint rocket science people it's a tapered nail having air sucked past it and siphoning fuel up thru a piece of brass with a hole in it

[JetdocX]

Harre, if you have a foam filter on one snorkle, the resistance might be causing you grief.   I have foam pre-filters on both snorkles and I tape about 1/2 of the second one closed.  Seems like a happy combo on mine.  Yours will probably be different, but it's easy to change back.

Your fuel mileage doesn't seem low to me, but i ride like an idiot mostly. :twisted: