strange problem with carb

A possibility to ponder: The taper of the needle may not be enough. I have heard of folks comparing the needles out of 2 or more stock carburetors and the tapers are different between them. You may need to lightly sand the needle with 300 grit or so sand paper to thin it out a little. Doing so will allow more fuel to enter the carburetor respective to the throttle slide position. Initially sand only the portion of the needle that is immediately above the jet protruding out of the floor of the carburetor throat when the clip is in the second position. I recommend assembling the carburetor with the needle clip in the 2nd notch and, considering how little the slide opening will be at the closed/ idle position, marking the needle carefully with a mechanical pencil with the lead waaaay out to be able to reach into the carb and actually reach the needle.

Sand the needle by spinning the needle with your fingertips on one hand while pinching the sand paper around the needle with the other hand. Go a little at a time and sneak up on the right needle diameter rather than sanding a whole bunch right from the get-go. Patience will be your friend.
 
i am using an NGK spark plug. right now i have a B6HS in there. but i also have B5HS, B7HS and B-4L (i think thats what its called. i havent heard anyone say they use these but its what napa told me was replacement for stock plug) and i believe i have it gapped right now at .022 . i also replaced the plug wire with an 8mm wire. although i am going to try something different because i tested the wire and it has twice the ohm's of the stock wire. so that means it has more resistance and not transfering as much spark. i have a wire i ordered from sick bike parts. and it has metal coil rapped in it. so im going to try that next. since everyone says its best to use a plug wire that has actual metal wire in it. i think its a "magnecor" wire.

i know the choke positions

i am mixing the fuel at 16:1 as that is what the directions that came with the engine said to use. then it said after break in (150 miles) to switch to 20:1 i am using regular 87 octane gas, even though the directions said to use 91 octane. but i dont see how with a low compression engine this makes sense. **** i dont even have to use 91 octane in my 74 chrysler newport with 400ci 2bbl

see whats funny is i feel like the engine is running to rich but when i look at the plug it will almost look too lean. i havent done the full throttle then shut off thing. but ill try it and see what happeneds.

and when i say it 4 strokes all the time i mean it 4 strokes unless i am doing hard acceleration.. if i stay at a steady speed it will start 4 stroking within 2-3 seconds. but if i turn it to wide open it will stop. but only if im pushing it real hard will it stop 4 stroking. i was riding some this morning and after it warmed up i put the clip back on the 2nd notch. and it seemed to 4 stroke alot then too almost just as much as on the 3rd notch. i also put an after market air filter i got from sick bike parts on. its the one they have for $17. when i put that on i noticed it wanted to bog down some times. and it never did that before. and when i would hold the throttle all the way open it wouldnt have as much power as before. then if i would let off of it just a little it would get going. not sure what to make of that my guess is it would do something like that if it was running too lean. but i dont know...

it also seems like it might have more power with the clip on the 3rd notch but i have to keep varying the throttle back and forth to get it to take off good. with it on the second notch it wants to bog down and i have to go wide open, then back off a little for it to get good speed.

as far as the bolts go. i really didnt tighten anything very hard. just tried to snug things down. its like you have to keep everything loose unless you want to stip it. i dont think i stripped the threads in the engine. just the left rear mount stud it self, from the nut.

ill try and post pictures but im not really sure how. but im sure i can figure it out...
 
and as far as trying to sand down the needle. i dont know if that is something i would want to try. especially since i cant seem to find anywhere that sells new needles... but i guess if i cant seem to get things figured out by trying everything else. it might be a last resort. does anyone know if anyone sells new needles, springs, clips... i havent seen them anywhere
 
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