still having jetting issues. ive been using the stock mikuni carb, and have a 340 main and the pilot that came with the vitos kit. tried several different size mains, and the stock pilot, and still getting very bad bogging/popping at WOT mid 3rd gear/low 4th gear. anyone have any suggestions? really itching to ride, and super super frustrated! please help! side note: after doing several plug chops with several different main jet sizes, a 330 main left my plug the appropriate tan/dry color, but now with a 340, needle in the 2nd position from the top, and the stock pilot, my plug is dry and white/grayish.
vito's big bore
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try a K+N highflow airfilter and then get a prefilter for it then put you jetting to like 300
bogging and popping? you checked your head nuts to see if they are loose. popping is usually a headgasket. you need to perform a leakdown test bad dude before you burn up that piston.
that was kind of my fear. my head nuts are torqued to spec, and i did a compression test after work and found after about 10 kicks holding the throttle open, i had 150psi. not sure of what i should be finding with the BB kit? i think tomorrow im going to pull the head off and see how the cylinder looks.
compression test and leak down test are completely different. that is great compression but that won't tell you if you are sucking air somewhere. there is a diy on how to build one. or they are forsale in the marketplace forsale section. A leakdown test is a must when you take anything apart on the topend.
if your using a stock carb with a 240 kit you;ll never get it jetted . 26 mm carb does not meter enough gas to mix with the air the jug pulls. lean lean lean, been there done that, get aleast a 30 mm carb ,34 is ideal, you can jet that carb to the moon and it will still be lean
u can jet it right with the stock carb u just wont make the max power you could with the stock one
you should be using a bigger pilot jet (minimum +2 or 3), a richer than stock needle setting, and I would start with a 360 main. You want to jet from the bottom to the top not the top to the bottom. you should first increase your pilot and set you air screw/idle then move to your needle and then the main. a stock 26mm will do alright in the low to midrange but you will lose power on top compared to a larger carb.
If your bogging, its rich, On my Vito's 240 I ran a 330 main with needle clip on second position down from top, stock needle, had a UNI filter on the stock cage, stock pilot and air screw about 1 turn out, 32:1 pre-mix, thing friggen ripped!! Not sure what your altitude is but mine was about 20 feet above sealevel. I've been told that an air striker carb I think 33 or 35mm works best, Hope this helps.
you can have a lean bog and a rich bog and they sound differently. i would rather start rich and lean it out than start lean and burn it up.
well another thing that can do this that people over look is cracked reeds, happened to me, and i went through i dont know how many trial and errors, switching sh*t, worth a shot, but personally i would check for air leaks first before taking things apart, do yourself a favor and get a 34mm carb, that puny sh*t u got is def not good for the 240.
cheap is not best, get a 34 mm carb and boot and modify your stack. and you wont have to worry every time your wot, is it gonna blow,good luck, if it worked so well everyone would still have stock carbs, think about it
has this motor passed a leak-test ?
prob lean from tiny air leaks
i sell leak-testers for 30 bucks shipped pm me
prob lean from tiny air leaks
i sell leak-testers for 30 bucks shipped pm me
Leak down tester to the rescue! it's a bird it's a plane it's holeshotman! he can hear an airleak 200 miles away! LOL! JK
i hope you're joking........................white/greyish plug means he's leaaaaaaaaaaan and most likely has an air leak, so lets bump the main down and burn it up I:I
time for a leakdown test
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