Need help getting it started

I got a replacement spark plug (autolite model #425) and a spark plug lead (omnispark model 7d125). Unfortunately the spark plug lead if a little to big (fits the spark plug but doesn't fit the cdi)

it also has a big metal loop on the end that if i squeeze a little i can make it fit in the cdi.

i just tried to fire it up and still nothing. i think the hose is to big. anyone know a good one i can get from o'reilly's? you can check their parts online and tell me which model # to get, id appreciate it.

tried starting it with kill switch attached. its 6:00AM still super dark and freezing out so i didn't feel like trying to untie it. I will try it later today with the kill switch wires untied.
 
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When you can't start it - first thing is ALWAYS to unhook the killswitch.

Blue engine to Blue cdi. This is the power coming in from the magneto to the cdi.
Black engine to Black cdi. This is the ground.

Personally, I wouldn't go changing the sparkplug and wiring just yet, as you don't want to make a problem where you're not sure there is one. Before you ever change out the lead wire, check it with a continuity tester. You will want to change it eventually, but don't go mussing with it when you don't even have a diagnosis.

Next, put the manual in the drawer, it won't help - it will only confuse you.

Honestly, if you're trying to start it like in that video, stop now. Just pedal start the dang thing, especially if it's cold. The guy in that video already had the machine warmed up and primed. I can start mine with a hand on the back wheel and the clutch engaged if it's a nice hot day. Now that winter is set, I have a 15 yard stint before it gets going.

Go through the basic 2 cycle troubleshooting diagram.


(Stage 1) Determine the source of the problem.

Do you have compression?
Do you have fuel?
Do you have air flow?
Do you have spark?
 
ex42k9j said:
I got a replacement spark plug (autolite model #425) and a spark plug lead (omnispark model 7d125). Unfortunately the spark plug lead if a little to big (fits the spark plug but doesn't fit the cdi)

it also has a big metal loop on the end that if i squeeze a little i can make it fit in the cdi.

i just tried to fire it up and still nothing. i think the hose is to big. anyone know a good one i can get from o'reilly's? you can check their parts online and tell me which model # to get, id appreciate it.

tried starting it with kill switch attached. its 6:00AM still super dark and freezing out so i didn't feel like trying to untie it. I will try it later today with the kill switch wires untied.
Click to expand...

If you are replacing the spark plug wire, after you remove the old wire clean out the hole with some small tools (exacto knife, small nail etc) until the hole is clean and the screw is visible. Then CUT ONE END OFF THE NEW WIRE, hopefully the wire will then fit in the hole and thread down on the screw. When you purchase the wire you should have tried to choose one that is about the same size around as the original, then it will fit! I went to O'Rielly, asked them for single plug wires, they produced a box from behind the counter full of various single wires. I choose what was labeled as a coil wire, it had a right angle spark plug boot on each end and was about 3 feet long. I was able to cut this wire in half and have a wire/boot for two motors, all for about $4 bucks.... Make sure when you install the new wire you coat the outside with silicone, then silicone around the wire where it mates with the cdi after it is installed, to seal it from water and kinda glue it in place.
As for getting her running... get your wire straightened out, disconnect your kill switch (for now, until you have her running), make sure you have cleaned your gas tank and verify that fuel is flowing from it, pull your plug and check condition, if wet dry out the plug and turn the fuel valve off on the tank then wheel the bike around with the motor engaged and throttle full (be very careful to isolate any spark or flame because gas is probably gonna come out the spark plug hole). After you have cleared out the flood of gas with the above method reinstall the plug, turn the gas back on and give her a ride, pop the clutch and keep pedaling while you apply throttle until she fires.... That's what I had to do to get mine running on first try....
 
ex42k9j said:
I got a replacement spark plug (autolite model #425) and a spark plug lead (omnispark model 7d125). Unfortunately the spark plug lead if a little to big (fits the spark plug but doesn't fit the cdi)
Click to expand...

Sounds like you have a 8mm plug wire...it takes a 7mm plug wire.
 
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no, i do have a 7mm plug wire, says so on the wire. i cut a little section of wire above the metal ring and there is a white wire inside with a small hole. It fits in the cdi.

disconnected the kill switch, still nothing.

tried to check for spark (let me know if i did it wrong). disconnected the spark plug from the motor, connected it to the hose which was inserted in the cdi. then i pulled the clutch in to free the back wheel and lifted the back of the bike to turn the back wheel while watching the spark plug.

i did not see any sparks.

as i pop the clutch back in while riding it that little 10 feet as i get towards the end i can hear the compression (or probably just the disks re-gripping and ive been told not to intentionally ride with the clutch lever not pulled in).

EDIT:

hose, plug wire, its all the same thing. i'm no mechanic, clearly.
 
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ex42k9j said:
no, i do have a 7mm plug wire, says so on the wire. i cut a little section of wire above the metal ring and there is a white wire inside with a small hole. It fits in the cdi.

disconnected the kill switch, still nothing.

tried to check for spark (let me know if i did it wrong). disconnected the spark plug from the motor, connected it to the hose which was inserted in the cdi. then i pulled the clutch in to free the back wheel and lifted the back of the bike to turn the back wheel while watching the spark plug.

i did not see any sparks.

as i pop the clutch back in while riding it that little 10 feet as i get towards the end i can hear the compression (or probably just the disks re-gripping and ive been told not to intentionally ride with the clutch lever not pulled in).
Click to expand...

I don't know how to answer really, "the hose which was inserted in the cdi", HUH??? Hose?
The CDI has the Blue and Black wires, and the spark plug wire, no hoses... If you really need to check for spark you should (turn off fuel) pull the plug, connect it back to the plug wire and you need to ground threaded end of the plug somewhere (with a jumper wire or leaning it agains the motor). Then you need to turn over the motor and watch for spark.... Make sure you don't set yourself on fire, you are messing with spark and fuel here after all....
Back to the CDI... I am getting that you have already removed the original spark plug wire from the CDI? If so, you need to clean all the rubber and glue out of the hole, reveal the wood screw in there which is what makes the electrical connection to the plug wire, cut the new plug wire exposing the conductor in the center and thread the wire onto the wood screw and silicone in place....
If you havent pulled the original plug wire yet I would just work with it until you have it running, it's not good to create extra variables and potential points for failure. The factory wire and cap will work good enough until it breaks....
 
i understand how the wires are to be connected what i dont understand is the terminology.

ground threaded end? jumper wire? leaning where against the motor?


yes the wire was removed and replaced.

side note ~ my spark plug is not wet at all.
 
Honestly - I think I know what's going on, it's been a hunch since I first saw this thread.

Are you sure your clutch is grabbing? Without seeing and hearing and being there, it's a pretty big assumation, but I think I'm right.

In the event that I'm wrong about that, your problem lies in fuel delivery. Make sure your fuel petcock is on. You'll know it's on because the lever will be lined up with the fuel line.
 
ex42k9j said:
no, i do have a 7mm plug wire, says so on the wire. i cut a little section of wire above the metal ring and there is a white wire inside with a small hole. It fits in the cdi.

disconnected the kill switch, still nothing.

tried to check for spark (let me know if i did it wrong). disconnected the spark plug from the motor, connected it to the hose which was inserted in the cdi. then i pulled the clutch in to free the back wheel and lifted the back of the bike to turn the back wheel while watching the spark plug.

i did not see any sparks.

as i pop the clutch back in while riding it that little 10 feet as i get towards the end i can hear the compression (or probably just the disks re-gripping and ive been told not to intentionally ride with the clutch lever not pulled in).

EDIT:

hose, plug wire, its all the same thing. i'm no mechanic, clearly.
Click to expand...

you cant check for spark with the clutch lever pulled in .let the lever out and turn the back wheel.
 
ex42k9j said:
yeah the fuel thing is on, i see fuel in the gas line/hose.

i installed my clutch like so:

How to buid a motorized bicycle Part 8- The clutch - YouTube

what do you mean by catching? if it wasn't i would be able to move my back wheel right? (pulling in the handlebar clutch moves the clutch arm just like in the video, far back enough to release the rear wheel and not piano wire tight.)
Click to expand...

When the clutch is engaged, you should not be able to easily move the back wheel. What I'm suggesting is that there's a chance the clutch is slipping. Just because there is resistance, doesn't mean that it's fully catching.

To check for spark you unscrew the sparkplug, leave it hooked up to the cdi and lightly roll the bike, watching the plug for when it sparks at every revolution of the motor. With the sparkplug removed, there will be no compression, which means there will be no resistance.

I don't think you have an electrical problem if the sparkplug is dry though. Your problem is you have no fuel making it into the combustion chamber, so the problem will be the carb or tank. Remove the fuel line from the carb and turn on the gas from the tank. We want to be sure the tank's petcock screen isn't jammed up from the factory. Though you might see fuel in the line, it might not be enough flow to make it into the motor.
 
ex42k9j said:
yeah the fuel thing is on, i see fuel in the gas line/hose.

i installed my clutch like so:

How to buid a motorized bicycle Part 8- The clutch - YouTube

what do you mean by catching? if it wasn't i would be able to move my back wheel right? (pulling in the handlebar clutch moves the clutch arm just like in the video, far back enough to release the rear wheel and not piano wire tight.)
Click to expand...

For clarity.... Normal condition/operations

Clutch engaged.. Releasing (no hands on) the handlebar clutch lever. Engine when running should propel the bike forward. Normal driving condition. Clutch flywheel making contact with clutch pads. Rolling the bike forward will rotate the chain and try to turn the engine over (Start) Clutch is refereed to as catching by some. Use this when testing spark plug spark. Plug removed, spark plug base grounded to engine. Best seen at night. Little to no tightness on the clutch cable.

Clutch disengaged.. . Squeezing the handlebar clutch lever. Engine running the bike should remain still, as engine running while at a stop sign. No contact between the flywheel and the clutch pads (not catching). Used while peddling before starting the engine. Should be able to peddle the bike with engine running or not. Clutch cable tight like a piano wire.

By pulling the clutch handlebar lever and pressing the pin down in the clutch handle (at the same time releasing the handle) is the same as the clutch being disengaged.

Slipping is refereed to as some contact (not enough to start the bike (clutch engaged) or bike movement when clutch is disengaged), with the flywheel and clutch pads..this is not a normal operation.
 
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well i feel dumb. i added more fuel (i only added like a cup to the bike cause i was having leaking issues that i fixed when i get that better hose~just forgot to add more fuel), warmed the motor a bit, took it out front and ran it down my driveway, motor sounded like it was starting up when i slowly popped the clutch out.

only thing, as soon as i stop pedaling, the motor stops and i can't get it to sit idle. i tried giving it gas (twisting the throttle) while pedaling and i got no acceleration. i pedaled 1/2 way down a steep hill and as soon as i turned around to peddle up the hill, the motor died on me. and yes, i have choke on (all the way up)


EDIT:


doing some research, i should:

pull handlebar clutch in
start pedaling
slowly let handlebar clutch out until motor starts turning over
keep pedaling and turn choke down half way (still holding that position on the handlebar clutch)
let the handlebar clutch all the way out and the motor should start
turn the choke all the way down (after a minute or two of ridding cause its cold?)

also, i checked the spark plug, it is shiny wet
 
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ex42k9j said:
well i feel dumb. i added more fuel (i only added like a cup to the bike cause i was having leaking issues that i fixed when i get that better hose~just forgot to add more fuel), warmed the motor a bit, took it out front and ran it down my driveway, motor sounded like it was starting up when i slowly popped the clutch out.

only thing, as soon as i stop pedaling, the motor stops and i can't get it to sit idle. i tried giving it gas (twisting the throttle) while pedaling and i got no acceleration. i pedaled 1/2 way down a steep hill and as soon as i turned around to peddle up the hill, the motor died on me. and yes, i have choke on (all the way up)


EDIT:


doing some research, i should:

pull handlebar clutch in
start pedaling
slowly let handlebar clutch out until motor starts turning over
keep pedaling and turn choke down half way (still holding that position on the handlebar clutch)
let the handlebar clutch all the way out and the motor should start
turn the choke all the way down (after a minute or two of ridding cause its cold?)

also, i checked the spark plug, it is shiny wet
Click to expand...

ok here is where that little screw with the spring on it on the side of the carberator comes in...it is you idle adjustment screw turn it clock wise till it idles...you may have to play with it a little bit.
 
am i suppose to adjust it, then try to ride or adjust it while pedaling?

what about the starting procedure i mentioned, is it right? what about the choke?

manual says to pop the handlebar clutch all the way out and keep pedaling until the motor starts and i get mixed answers with the choke. some same it wont start if the choke is all the way up, others say it must be up, some say in the middle, im confused.
 
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Here's some tips -

First - leave the choke alone, honestly, on these chinese motors it's unnecessary - even before breakin.

Second, when starting your motor, drop the clutch all at once. It's unnecessary to do it gradually.

Third. The idling issue could be two things. The first is the idle speed, which you adjust with the cable tension on top of the carb and the throttle grip, and also the idle adjustment screw on the side of the carb. As well though, the clutch could be grabbing when it's disengaged, putting extra stress on it and killing the motor.
 
DuctTapedGoat said:
Honestly - I think I know what's going on, it's been a hunch since I first saw this thread.

Are you sure your clutch is grabbing? Without seeing and hearing and being there, it's a pretty big assumation, but I think I'm right.

In the event that I'm wrong about that, your problem lies in fuel delivery. Make sure your fuel petcock is on. You'll know it's on because the lever will be lined up with the fuel line.
Click to expand...

I seem to recall hearing him mention hearing compression, which would indicate the motor turns over and clutch is working...
 
ex42k9j said:
well i feel dumb. i added more fuel (i only added like a cup to the bike cause i was having leaking issues that i fixed when i get that better hose~just forgot to add more fuel), warmed the motor a bit, took it out front and ran it down my driveway, motor sounded like it was starting up when i slowly popped the clutch out.

only thing, as soon as i stop pedaling, the motor stops and i can't get it to sit idle. i tried giving it gas (twisting the throttle) while pedaling and i got no acceleration. i pedaled 1/2 way down a steep hill and as soon as i turned around to peddle up the hill, the motor died on me. and yes, i have choke on (all the way up)


EDIT:


doing some research, i should:

pull handlebar clutch in
start pedaling
slowly let handlebar clutch out until motor starts turning over
keep pedaling and turn choke down half way (still holding that position on the handlebar clutch)
let the handlebar clutch all the way out and the motor should start
turn the choke all the way down (after a minute or two of ridding cause its cold?)

also, i checked the spark plug, it is shiny wet
Click to expand...

I have a real hard time following what you are saying, cause first you say "Warmed the motor a bit" then you say "motor sounded like it was starting up when i popped the clutch". Is the motor running or not??? On one hand you seem to be saying you warmed it up (I assume this means it's running) then you say it sounds like it is running but does not run when you let the clutch out. This usually means you are pedal powering the motor and it is not actually running (I have seen a few people saying similar). When the motor is running you should KNOW IT! You can make the motor turn over by pedaling it, you will hear compression and the sound of the motor "running" but that doesnt mean it is firing. When it fires you will know!

I notice in your pic that your carb has a pretty heavy lean forward, you might want to adjust your choke to lower the fuel level in the bowl a bit, that big a lean is bound to effect the way the carb functions.

Your startup list is a little confused.... You pedal then release the clutch and right then the motor should start running, not when you pull the clutch back in.... It should remain running when you pull the clutch in, but it starts when you let it out.
Has this motor EVER run? Have you felt the pull and heard the POP when the fuel combusts? Does the plug look NEW and dry, or can you see it has fired?
On first run sometimes you need to pedal quite a while with the clutch out, turning over the motor by pedaling (NOT running), with the throttle wide open, when the fuel finally hits the cylinder she should fire....
 
ex42k9j said:
am i suppose to adjust it, then try to ride or adjust it while pedaling?

what about the starting procedure i mentioned, is it right? what about the choke?

manual says to pop the handlebar clutch all the way out and keep pedaling until the motor starts and i get mixed answers with the choke. some same it wont start if the choke is all the way up, others say it must be up, some say in the middle, im confused.
Click to expand...

No need to be confused about the choke, every motor runs different due to many factors such as altitude, barometric pressure, temperature, carburetor adjustment, cylinder size, fuel mix etc... oh, wait, maybe you should be confused! LOL

Since every build is different these factors vary, that's why you have people saying different things about the choke. If your running rich or living in a warm region you might never need the choke, if your running lean or have to start up in the cold you might need it a lot...

The choke is there to make the motor start easier when cold and help it run better until it is warm, after the motor is warm you shouldn't need the choke. In some cases you might not need the chokes help to start, in some cases the bike will ride better when cold with the choke on but will not idle when you let off the throttle, at that point you can usually let off the choke and she will idle. Again, the choke should only be needed (if at all) for the first few moments the motor is running and then it should be turned off...
 
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