Bike wont start - New Build

[Silver Surfer]

Hi All,

This is my first time building these kits. Ordered a 80cc off amazon and followed all instructions online.

Bike makes that brrrr sound when I release the clutch and it just dies down when I stop pedaling.

I Have spark, I re installed my needle valve C clip inside the carb and looked inside while turning the throttle to make sure it was moving. My clutch cable is also tight. I took apart my coil cable and exposed the wire as well to make sure I'm getting spark as well.

Fuel is full and Before I start my fuel line is on and my choke is pulled back just slightly from close about 10%. I pressed the release spring at the bottom of my carb to make sure there is gas and the carb is full of gas.

My gas line is not always full of gas when I turn it on it drops a bit of gas down but doesnt consistently flow, is that correct?

Not sure what else to do. I've tried starting it on 3 different ocassions (6 times each occassion), my quads are tight as hell from trying to start this thing. Lol. Please help.

 

[Silver Surfer]

Some more pics

 

[neodymium]

I would try pulling the plug when trying to start it and see if the plug is wet. If not your issue is fuel supply.
You can also test this by spraying carb cleaner or starting fluid into the intake port and trying to start, it it pops or attempts to start it's definitely not getting gas.

Problem with the Amazon or eBay kits is there isn't any quality control usually so it could be literally anything.

I would also make sure you don't have a head gasket leak and good compression as you already said you have spark

 

[neodymium]

My gas line is not always full of gas when I turn it on it drops a bit of gas down but doesnt consistently flow, is that correct?

This is normal as the float in the carb will prevent gas from entering the bowl when it fills. Fuel will flow when it is needed, air in the fuel lines is usually normal as long as there is SOME gas in the lines the carb will have enough, these engines sip gas to begin with so you aren't going to see the flow unless you're wide open

 

[DAMIEN1307]

Many of these kits come though with the gas cap not venting properly and can vapor lock your gas tank from giving it a full feed.

Try loosening the cap this time so it has free air flow before trying it again...If it works ok this time, thats the problem.

 

[weefek]

First of all thank you for actually including pictures, most people don't. Nice looking bike.

1) How long are you pedalling without the bike firing off (50ft 100ft etc)? Have you checked the plug afterwards (it's easy to see the fuel on the plug, if the plug is dry that can be telling).

2) Clutch cable shouldn't be "tight". There should be an extremely small amount of play with the clutch disengaged. (1/16th of an inch roughly).

3) I've heard of people with the stock spark plug that came with the kit having terrible troubles/issues. I'd recommend a proper NGK spark plug (do some searching here to find the PN it's easy to find).

4) Try with the choke on 100%, wait until the bike starts firing, let it idle and ride for about ~20 seconds, then kill the choke.

All the other recommendations are equally as possible and valid. Gas caps can cause pressure issues as well. This kind of refers back to my #1 checking the plug.

 

[Risk Man]

I have had an issue with my 48cc requiring full choke and peddling for nearly two blocks. I always thought I was flooding it.... but when not ridded for a few days, it takes a long time for it to fire. Yes, it needs to be adjusted, but once it is up and running, 35 mph is easy to reach.

 

[Silver Surfer]

First of all thank you for actually including pictures, most people don't. Nice looking bike.

1) How long are you pedalling without the bike firing off (50ft 100ft etc)? Have you checked the plug afterwards (it's easy to see the fuel on the plug, if the plug is dry that can be telling).

2) Clutch cable shouldn't be "tight". There should be an extremely small amount of play with the clutch disengaged. (1/16th of an inch roughly).

3) I've heard of people with the stock spark plug that came with the kit having terrible troubles/issues. I'd recommend a proper NGK spark plug (do some searching here to find the PN it's easy to find).

4) Try with the choke on 100%, wait until the bike starts firing, let it idle and ride for about ~20 seconds, then kill the choke.

All the other recommendations are equally as possible and valid. Gas caps can cause pressure issues as well. This kind of refers back to my #1 checking the plug.

Thanks for everyones responses so far.
@weefek, to answer you questions:

1) I'm testing it around 50 to 100ft each time inside my parking garage. I let it try to fire up for around 5 to 6 secs each time. I feel like I'm damaging the engine everytime it doesnt start. I pulled the spark plug out and it looked very slighly wet. How wet is it supposed to be? How will I know if I have flooded the engine? my carburetor is very simple, no float lever or prime button either.

2) will check it.

3) I'm ordering a new ngk b6hs plug.

4)will try it.

 

[DAMIEN1307]

no float lever

What brand or kind of carburetor are you using that doesn't have a float lever in the bowl???...That carburetor looks like a BoFeng to me and it definitely has a float and lever inside the bowl.

I did notice also that you seem to have quite an angle on the motor which is not bad in itself but the carburetor needs to be more level or it just will not start or run correctly...These carbs don't do well at all if angled more than 10 degrees off of level because everything is gravity feed, no fuel pumps here.

 

[Silver Surfer]

What brand or kind of carburetor are you using that doesn't have a float lever in the bowl???...That carburetor looks like a BoFeng to me and it definitely has a float and lever inside the bowl.

I did notice also that you seem to have quite an angle on the motor which is not bad in itself but the carburetor needs to be more level or it just will not start or run correctly...These carbs don't do well at all if angled more than 10 degrees off of level because everything is gravity feed, no fuel pumps here.

It's a bofeng like the attached. I'm fairly new to these parts so excuse my ignorance here lol. I didnt know there was a lever inside to adjust.