bike wont start cant figure out why?

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if I was going to keep the bike I would totally get one, but im just fixing it to sell so I can buy a different bike.
 
ok I got gas last night, I put it in and... no good. it turns over, fires for a split second, keeps turning and just repeat the process for few seconds then backfires and shoots smoke. maybe the timing is off. but then I checked the oil and it was over filled. not sure how because I had filled it a few weeks ago right in between the fill lines. so I drained it back to were its supposed to be and know it doesn't shoot smoke or fire for a second. im not sure what is causing this.
 
so im getting air, and getting spark, so now I need to focus on fuel. its not floaded and I cant smell fuel, so I know its not getting enough fuel. (if my logic is correct). so what do I adjust, do I shim the needle or adjust my auto enricher. or both. if needle were do I get the shims?

jetlee- I have watched your 2 videos on youtube about tuning your cv40 carb, and adjusting your auto enricher. so know I now how to do it. awesome videos man! just I don't know which one to adjust, the needle or the enricher?
 
I should also mention that because the manual says run 87 that's what I got. I think its still trying to burn off the bad gas that's in the engine.
 
I actually have four videos about the carburetor...watch them all. (thanks for the compliments)

Make sure you have ALL the parts properly installed in your carb (jets, emulsion tube, collar)

1.If you haven't adjusted your auto-enricher, DON'T. If you have, set it to half-open when cold (ambient temp) like my video shows.
2. Put your needle to stock, it really doesn't matter for start/idle.
3. Put your jets to 45/170 (unless you have aftermarket exhaust, then 45/175).
4. Turn your idle mix screw out 2-1/2 full turns (900*) from soft-bottom (just barely bottomed out).
5. Check your ignition timing following the manuals instructions or this video.
6. Check compression, you need 130psi at least.
7. Check for spark at the plug (just to be sure, since you have it out for the compression gauge anyways)

If that doesn't work...where do you live?
 
i haven't adjusted my auto enricher. needle is at stock my jets are stock also, I don't have a compression guage so ill have to buy one and I have spark at plug. it shouldn't be some big issue since the bike is almost brand new and it started before I brought it to my house on a trailer. im going to pull the carb off and adjust the idle mixture screw how you said to do it.
also, I live in Katy, Texas.
 
i just took the carb off and adjusted the air fuel mixture screw to 2 -1/2 turns from soft bottom. and when i took the carb off i realized i didn't plug back in the auto enricher and throttle positioning plug! i wonder if that was why it didn't start after i changed the fuel. it would fire and die and fire and die ever other second so i guess because the enricher and throttle was off that might have caused it. im gonna put the carb back on, plug that in and see it it will fire.
 
ok so i just put the carb back on and pluged the thing in, put all the stuff back on and....still no good. now im getting frustrated. i have tried almost everything you can do. i took the jets out and sprayed w-d40 through them them wiped em dry. i also wiped the needle off cuz it has some gunk on it. then i poured all the old gas out of the carb, and wiped the whole thing clean. i also did the air fuel mixture like you said. i guess il post a video later today of what its doing. i also took the timing cover off and the led light is not on. ( with the key in the on position). i don't have a bit big enough to take that bolt out of the whole. does it have to come out to move the timing box so i can get the light on?
 
I use a big flat-head to take the plug out. You have to get the plug out to check the timing.

Take the carb back apart and clean it with "carb/choke cleaner", NOT WD-40.

Have you bypassed your kickstand safety switch and your BAS? Pull the plug and jumper the wires together.
 
well I didnt clean the carb with wd-40 I just wiped it with a towel. I only sprayed the jets after I took them out with it.
what does bypassing the kickstand do? and I don't have carb cleaner. its pretty clean, no gunk anymore. what is BAS? is that the clutch safety switch?
 
every one is saying you have to drill out the timing cover, but I just pop mine off with a small flat head. its plastic and bendy so it just bent and popped off. and in your video you didn't lift the rear wheel or put it in fifth gear or anything. is that on a different bike you do that? not on blast?
 
so I got my timing cover off, put my line at tdc, and the lights not on. the ignition module wont even move. I checked my battery and it was 12.3 so I put it on the charger. would a low battery cause the light not to come on? why wont the igniton module move?
 
I figured out how to get it to move, you just loosen the screws! but no matter how little or much I turn it the light doesn't come on at all.
 
every one is saying you have to drill out the timing cover, but I just pop mine off with a small flat head. its plastic and bendy so it just bent and popped off. and in your video you didn't lift the rear wheel or put it in fifth gear or anything. is that on a different bike you do that? not on blast?
Click to expand...
You don't have to drill it, just get it out with whatever method.

I don't lift the rear wheel in my video because I already had it in gear and just push the bike back and forth to get the line to line up.

Turn the engine over 360 degrees, you're likely at TDC on the exhaust stroke instead of TDC on the compression stroke.
 
is the compression stroke with the line, and the exhaust with the dots? im using the line. I read in a post that there are 2 dots, then there is a line. maybe that's on a different bike because im not seeing 2 dots.
 
ok so I rotated the wheel 360 and still nothing. then I rotated it 180 and nothing. is my ignition module bad?
 
ok so I rotated the wheel 360 and still nothing. then I rotated it 180 and nothing. is my ignition module bad?
Click to expand...
Not the wheel, rotate the crankshaft 360* so the line re-appears in the middle of the window.
 
He's trying to say that one full rotation of the back wheel is several rotations of the crankshaft... You only wanted to rotate the crankshaft a full turn, not the back wheel...

Think about it like this... Starting from the intake stroke of your motor, the crankshaft rotates 180 degrees to make it to the compression stroke, then the power stroke pushes it another 180 degrees to the exhaust stroke, then it's another 180 degrees back to the beginning of the intake stroke again...

Basically that's two 360 degree rotations of your crankshaft for four cycles in the engine.... Only ONE of these 360 degree turns needs to be timed for the spark plug to fire.... That would be TDC of the compression stroke... Jetlee was saying you were probably trying to time the motor when it was at TDC for the exhaust stroke.... That was the next 360 degree turn of the crankshaft... He was suggesting that you turn the crankshaft over again to get it on the correct cycle of the engine...

Make sense??... =)
 

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