help sym dd50 with af16e engine won't start

[Rip_City_Spree]

Would it backfire if it was firing at the wrong time? Did you try your old Cdi was it working before? IM no expert just something that just popped in my head.

[curtis966]

I checked compression comes in between 8 to 9 psi spark plug does get wet , when i put my carb back on i put all the tubes back but theres this little nipple thingy on the front of the intake mani that looks like a tube belongs there not too sure what to do with that. And i did put the piston in with the arrow faceing the exhaust port ..... when i try to start it it backfires and fire shoots out the exhaust

What is 8-9 psi? Needs to be in the 95-105 range just to run and I imagine the little nipple is for your vacume line. Can you upload a pic? And are you running the stock carb and mani? what jets? Stock pipe?

[aukinakaeo]

I just ordered new gaskets hopefully that helps i notice smoke leaks from the head when it backfires and sorry the pressure gauge i have reads in pressure per square inch and Lbs. Per square inch so 8 to 9 psi reads 120 to 130 lbs but i might be reading it backwards (my bad)i also tried swaping between my old cdi and the new racing one i got for free but it's still doesn't run i am running my stock carb and mani with idk what jets that it came with my bore kit want it to actually start and run before i fine tune everything also I have a v8 pipe on it but idk which model because my friend painted it black for that sleeper look it

[aukinakaeo]

I also have a 24mm and 28mm carb laying around and i was going to buy a ct manifold for it but i dont want to shed money on it if it wont even start

[ped]

Hi aukinakaeo. you're in Hawaii the scooter tuning capital of United States. Is there anyone that can help you out?
I don't think you should use the stock carb with the 50mm BBK. 50mm is a little to big.
try putting all your stock stuff back on see if willl start? Cdi, head, and the rest.

Hi forum. He needs help. Anyone?

[bonesv]

I'm almost ready to give up its really depressing i don't know what else to do i cleaned everything almost 20 times

You might want to do some reading up on these before you start modifying and making everyone guess as to what's wrong with your scooter. That is no way to be productive. It sounds like there is an air leak somewhere but no one here could ever tell you where it is. You have not told us your skill level with 2-stroke engines or if this is your first time working on these engines. Give as much intelligent information as you can and follow intelligent advice if you dare. Good luck.

[aukinakaeo]

I am no expert but i do know my stuff ive never worked on a dio before but ive built 2 stroke ktm and kawasakis bikes as a hobby to make some Xtra cash and yes i have installed my slide in correctly there's only one way it can go that allows it to slide all the way in. Also I'm new to the moped scene and i don't really know to much people who works on these bikes all my friends turn to me as the mechanic and i can't really go back to stock because i have ported the boost port

[aukinakaeo]

Also i have done a sh*t load of research before i even tackled this project that's why i chose this forum because I've read allot of informative facts and helpful suggestions scrolling thru this forum

[aukinakaeo]

And the oil pump is there but the shaft inside of it is not that's how i bought it but it ran great until i put in the bore kit . And another thing i just noticed was that my spark plug was replaced with this Autolite rubbish sparkplug who i think was my f**king dumb moped guy who came to check on my moped then said he doesn't know why it won't start so I'll have to replace it . Would running the wrong spark plug cause timing issues? Also yes i have a 24 and 28mm carb I'm just waiting for my intake manifold to come in the mail .

[kauaianman]

I checked compression comes in between 8 to 9 psi spark plug does get wet , when i put my carb back on i put all the tubes back but theres this little nipple thingy on the front of the intake mani that looks like a tube belongs there not too sure what to do with that. And i did put the piston in with the arrow faceing the exhaust port ..... when i try to start it it backfires and fire shoots out the exhaust

nipple in front of intake manifold needs to be blocked up. sucking a lot of air big hole in intake.

[aukinakaeo]

It's actually quite small but I'll get around in doing so. if i need to block it off why would the manufacture put it there

[Wheelman-111]

Greetings:

For someone who's boasting about his Kawasaki and KTM 2-stroke experience & skills, you sure don't seem to understand some simple stuff.

Quoth Aukinakaeo:

It's actually quite small but I'll get around in doing so. if i need to block it off why would the manufacture put it there

I recommend you get around to it soon, like before you burn your starter or strip you kickstart assembly. There is no point even trying to start it with an open 1/8' vacuum nipple open. Tiny cracks or badly-prepared gasket surfaces admit enough air to render the mixture non-combustible, or burn a hole in the piston if it does start and run. It backfires because it needs 3 or 4 completed strokes to have enough fuel to ignite. The manufacturer put the nipple there to put vacuum on the automatic fuel petcock. If it's not used, it needs to be blocked off.

By all means, toss the Autolite plug and install the proper NGK #8. It's good practice to replace this cheap item just to rule out a fouled plug. But the timing isn't determined by the spark plug. It sparks when the voltage hits it. I don't know enough about the differences between the DD and the Elite in terms of ignition timing, but if you got an aftermarket module or any other electronic component, consider putting the stock one(s) back for now too.

[aukinakaeo]

I was not trying to boast about my skill level it was just an example of my experience of 2 strokes because i dis like the way some people are inconsiderate of one another's feeling s and talk down to them like they are stupid , catch my drift ?. And yes i know i have a air leak in my cylinder . Also i checked the timing anyways and the little key on the end of my crankshaft broke off where the flywheel inserts any suggestions ? Or should i just go with a new crank ?

[bonesv]

I was not trying to boast about my skill level it was just an example of my experience of 2 strokes because i dis like the way some people are inconsiderate of one another's feeling s and talk down to them like they are stupid , catch my drift ?. And yes i know i have a air leak in my cylinder . Also i checked the timing anyways and the little key on the end of my crankshaft broke off where the flywheel inserts any suggestions ? Or should i just go with a new crank ?

My friend, I was giving you the best advice based on your input, and my experience. As they say, "the proof is in the pudding". Just replace the woodruff key and install the flywheel-then torque to specs.

[aukinakaeo]

I really have no idea how it broke im guessing Thas how i got it. Because the guy who sold it to me looked like a tweaker and everything on the bike was make shift with zip ties and random screws bolts also my wireing is kinda makeshift too only the head light and headlights work i have no turn signals