Need help with pred 224 and vm22

#1
Hello fellow minibikers, i recently purchased a baja mini db30, had the original 97cc engine and swapped out for a predator 224, since then I have removed gov, oil sensor delete and straight pipe, added the VM22 fakuni last week, since then I've been having issues, at first wouldn't even start, played with the A/F and idle settings got it to idle real good, idle to 1/4 throttle was ok but after that just bogged and died, i changed main jet to a 130 and found some improvement but still boggy, i now have a 140 main, i then changed my needle jet to the 5th e clip position and low and behold it was all there, still some sputter at top end tho and my plug still hasnt really changed any color which leads me to believe im still on the lean side, ive watched numerous videos and all pretty much use 130 main and 15 pilot with the 3rd eclip on needle, i know it can vary but im getting into the unexplored areas lolol, Ive checked for air leaks throughout the entire engine even spraying starter fluid but nowheres would it suck, im just kinda confused at this point pretty much dumpin gas at 1/4 to 3?4 throttle and a 140 should be enough at top.....ive ordered a main and pilot jet kit to test, i went on a good 30 mile ride yesterday with little to no issue other then the small bogs while getting up to speed but no top end, just spits n sputters at WOT im not looking to blow this motor its brand new so any and all help, tips, info would be great, im looking to maybe get it to a "to rich" point so i can work my way back down to a suitable setup. Id rather have a to rich condition then to lean and blow it
 
#3
ive checked float level had to adjust to even it out with carb body (maybe to far? but was even with bottom of carb). it was overfilling bowl to where it was leaking out the overflow, checked where carb meets intake to make sure was lined up and carb is level as i can get it without losing the seal...... 20230917_113538.jpg
 
#4
not sure if its the pic but that carb doesnt look level at all...........but its to the end of slots of adapter, was told might need to install a fuel pump
 
#5
So you set float level by taking off float bowl holding carb upsidedown and float seam is parallel to the carb base, correct?
 
#6
Correct, made sure it was level with carb body, it does not leak from overflow anymore, i rode it to work tonight it preformed pretty good, accel was great off idle, idle was good, but stumbled after 1/2 throttle and cut in and out at WOT, insulstor on plug is starting to turn a tanish color now
 
#8
im not sure of exact rpm but at higher rpm it def sputters(as stated pretty much anything past 1/2-WOT cuts in and out) i will be checking valves tomo, maybe upgraded springs are needed
 
#9
sorry for the late response wasnt feeling the greatest but got out to check valves today....set both at .003 exhaust was around .005 and intake was already set at .003....snapped a few pics of carb and such just to get a look at what i got, i switched my main jet to a 150 with very lil impovement.. i will setting back at 130 and pilot jets will be here today
 

Attachments

#10
So valve float would occur at a specific higher RPM it would not vary, you are saying that from 1/2 to full throttle it is misfiring, is that correct? So even at low RPM if you open the throttle to full it will not run right at any rpm? If that is the case, and looking at your plug it sure looks like it is running lean or you have a weak spark condition. with a 150 jet at full throttle I would expect the plug to look black on the insulator. Your carb seems to be identical to the ones I use, I am including a picture of the needle jet holder, mine has a w stamped on it. Your picture of the gasket between head and manifold looks off the last pic is how it should look.
 

Attachments

#11
If i open the throttle from low throttle its all there...itll lift.. but thats only on the 5th needle clip, anything lower it spits n sputters the same (but soon as im at higher rpm yes it will cut in and out, if i hold at lower throttle its ok some spit n sputter but nothing major and i agree 100% the plug should be blackish by now, i did cut out the gasket so that theres no overlapping, made sure no leaks after reinstalling, i cleaned the outta the carb thinking maybe theres a port partially blocked not allowing fuel but it flows steady if i crack open the drain......ive read something about drilling holes in my gas cap? Maybe its getting airbound? I did take the hose off top of tank but left the fitting......im just looking at lil stuff i mighta missed lolol
 
#13
Ok so after some disassembly and assembly ive noticed this, this is where my manifold meets the engine, it does not line up at all and theres no way to align it as these are the single bolt holes...is this an issue? i did find the correct gasket for the manifold also like the one in your pic. lines up with engine perfect but manifold its off like head is
 

Attachments

#16
there is no leak at all there, refer to original post, that is the closest i can get the oring to be even AND the carb level on the bike...ive sprayed gas all over the engine and there is 0 air leaks
 

Minimichael

Well-Known Member
#17
So your mixture is falling apart in upper range. What's your needle i.d.? I've found setting the clip too high takes the needle out of the equation altogether near top end. Best to drop it back in and look at needle shape instead.
 
#19
i mean i never really thought about goin to a bigger carb seeing as this is the carb everyone goes to, no markings on the needle at all, whatever came with the fakuni, but my e clip is on the 5th groove, i went back to the 130 main from the 150, and i took it for a very lengthy ride today, bout 30 miles by the REVER app, performed well from idle thru almost WOT, still some spitter and sputter but im content with it for now, the rubber o ring i did get a lil better alignment on also....pilots never came so still waiting on that, ordered a tach also so i can get more accurate readings on rpm ranges, and my air filter fell apart onthe ride so im waiting on parts now lol
 
#20
Those carbs work fine. the misalignment of the manifold to the head is not your problem. It just your intake opening appears smaller for some reason Or the manifold opening is off. How does top of the port match up?
 
Top