No start wonder!

[Lincoln78]

I have a Few Questions That hopefully someone can answer for me, Im new to 2 stroke motors, so I need help with the Fuel Ratios...Like 16:1 would be 1 gallon of gas to 8oz of Oil ??? Thats what Bikeberry.com recomended for the break in period, but my bike will run great for a block or 2 then just dies, I have Adjusted the Needle to All the way up to Run Leaner, Maybe i need to Adjust it down all the way??? I just need Help figuring out the Fuel Ratio's, So ANY Help would be Great! TY Everyone!!

 

[biknut]

I have a Few Questions That hopefully someone can answer for me, Im new to 2 stroke motors, so I need help with the Fuel Ratios...Like 16:1 would be 1 gallon of gas to 8oz of Oil ??? Thats what Bikeberry.com recomended for the break in period, but my bike will run great for a block or 2 then just dies, I have Adjusted the Needle to All the way up to Run Leaner, Maybe i need to Adjust it down all the way??? I just need Help figuring out the Fuel Ratio's, So ANY Help would be Great! TY Everyone!!

That sounds a lot like what happens when the vent is blocked in the gas cap. A very common problem with the stock gas tanks.

 

[picklefish]

Alright so heres my deal, grubee skyhawk 66cc. ran fine till yesterday when I ran out of gas. I figured it was a good time to go ahead and make the 32:1 ratio oil which by my calculations meant 5.2 oz of oil to one gal of gas, well Im thinking I did 5.2 oz to a half gal of gas without thinking about it. Sure enough I got oil squirtin out of the exhaust manifold. So now the danged thing starts and wants to run but just doesnt have the get up and go. Tommorow I am going to drain the tank and mix up a batch of regular mix to the right ratio which for me is going to be 2.6 oz oil to the gal. synthetic oil and its the mix my bike seemed to run the best at. My question is, will the extra oil in the gas as it sits overnight clogg any jets or mess anything up?

 

[Norman]

You shouldn't have a problem with what's in the carb bowl for a couple of days, but you can drain the float bowl on some carbs or you can remove the float bowl to empty it.

 

[Mungface78]

So I recently finished my first bike 2 weeks ago and it ran great for a few days then while I was riding it slowly started to die and wouldn't start back up. I ditched the stock spark plug and got an NGK b6hs. Still no start, brought out the volt meter and magneto checked out fine cdi didn't. I bought a new cdi and went out to crank her up and got 2 pops no start. Pulled plug and it was flooded and fuel coming out the exhaust. Then I took apart the carb (speed carb) and It had some bits of plastic like pieces in the float bowl area and the pin thing above the float. I cleaned that out and adjusted the float lever down a bit so as not to flood the motor. Also set the needle to the 2nd notch on the top. Spark plug is gaped to .028". Today I used starting fluid and it started but would not hold an idle. Had to hold throttle open full and it still died. Kept trying but only got pops. Should I set the needle back to the 3rd (factory setting) position? Any help would be appreciated.

 

[Greg58]

One of the best rules when working on a m/b is do one thing at a time, that way you'll know if what you just did helped or hurt. If the engine started flooding all of the sudden it probably had debris in the needle and seat, it might not be a bad idea to go back and give it a try. I would put the float back up a little also, it may be too low.

 

[Mungface78]

I'm going to try again in the AM but just wondering what can I do to keep her idling.

 

[Mungface78]

Also, why is it so hard to start?

 

[Greg58]

I always turn off the fuel to the carb after a ride. So what I do on both of my bikes is turn on the fuel then hold down the tickler button two to three seconds then raise the choke, after i get up to speed I release the clutch , once it fires I lower the choke a little so it stays running and let it warm a bit before ridding. This has worked for me every time. Turn the idle screw clockwise will raise the idle.

 

[Mungface78]

I think the floats ok, spark plug was loaded with fuel.

 

[Mungface78]

Idle screw is almost maxed.

 

[GearNut]

Mungface, That sounds like a massive air leak to me.

 

[Henshooter]

Mungface, That sounds like a massive air leak to me.

I have to agree with GearNut , my build had identical issues reciently ,I flushed the carby fully ,cleaned the pin and jet ,checked the float and brass tang ,checked the inline filter on the tank and as such the fuel flow to the carby , turned out to be an air leak where the carby joins the inlet manifold ,the carby needs to sit very flush on the manifold or you will get air leaks in the 3 slits on the carby (the part that slides on the inlet) ,as soon as I had the carby on flush with the inlet manifold everything returned to normal .

Check the fuel flow aswell these bikes work on gravity feed ,if there's a blockage the motor will starve .

 

[Mungface78]

I put silicone between the intake and carb(forgot to mention that). I did notice a bit of air in the fuel line, but it was getting fuel as the plug was soaked. Should I take the carb apart again and double check? Thanks you guys so far for your input.

 

[GearNut]

If the carb is not flooding, I would leave it alone for now.
Are you using the factory spark plug cap? They have caused all sorts of trouble on new builds and should be replaced with one from a motorcycle shop ASAP. Alot of folks recommend replacing the spark plug wire and cap as an assembly with one for a car.
Also, it could be that the spark plug itself is bad, even if it is brand new. Brand new does not always mean good. They can spark just fine while sitting on top of the cylinder head but when put under the stresses and pressures of a combustion chamber they fail.

 

[Mungface78]

Well I'm 99.8% sure I've found the problem, on the magneto one of the solder joints broke loose not the one on the black or white wire the one coming from the copper windings to the magneto "frame". Goin to head over to my pops house and dig out his solder iron. Looks like the factory did a piss poor job with the soldering on the mag.

 

[GearNut]

Good troubleshooting!
I am a bit embarrassed that I did not mention this yet, but each and every soldered connection on the mags are well known for having cold solder joints.
Most surprisingly still work well, others need the all connections cleaned and re-soldered properly.

 

[Mungface78]

Thanks you guys! Bike is running great!

 

[Nickton]

Very good thread here. I gave up on trying to start mine, after a full rebuild with new head, cylinder, bearings, magnet, clutch pads, carb, and more.... After making sure I sanded the contacts and did a few other things including testing for spark, I just put it aside and haven't looked at it for about 5 months. I'm probably going to sell it to a friend for 100 bucks, even after all that work. But reading this thread might get me to give it another go.
One thing I noticed that surprised me was that after buying two new upgraded plugs-- an irridium, and an ngk, I found I got no spark from either one, while an old cheap Chinese plug did spark, though weakly.
My engine was used and came with quite a few parts, including about ten of those cheap plugs, 3 new carbs, and 4 coils, including a panther one that did not work.
I've been thinking I may need a different coil, or maybe the head is not correct, since it was different from the original one.

 

[Greg58]

If you replace the coil or CDI make sure they are a match for the magnet you have, some of the newest styles that are called high performance or super CDI's use a magnet with the keyway cut in a slightly different location.