Baja 250, No Spark , I'm stumped ...

[Mhatayas]

My uncle bought a Baja 250, 2006. Knew there was no spark since the get go. He don't know anything about quads so is getting me to help him try to get it running...

 

battery is bad so I connected battery charger to it to crank it over , cranks over well , but no spark .... 

Lights and everything work fine , but with each crank over using the e start switch , the display reads 999 888 777 666 ... Right down to 000 and repeats itself . 

 

He managed to get a parts bike , I changed over the CDI and the coil and the stator from the parts bike and there was another black box by the voltage regulator I changed over ... I used my multimeter to confirm as much as I could works , it's hard without knowing which wires are which , and I cannot find any diagrams online for this bike ? 

 

Do you think it could be the Killswitch? There's so many wires coming from there I don't know where to start . Also I should mention it appears the fan on the front of the bike has been taken off (the wires have been cut too ) 

 

If this bike sparked it would run . The previous owner said he parked it one day and it just wouldn't start after.

[Mech]

Most handlebar switches can be dismantled and cleaned.

[semicolon]

Try checking the kill switch contacts and also the neutral switch. 

[Mech]

You need a battery too. That dash display going screwy is because the voltage is dropping too low when you are using the starter. The charger isn't supplying enough power to run the starter.

If it cranks too slow because of not enough battery power then it might not make spark, and if the cdi uses 12v it won't work at the very moment it needs to, just as the piston's coming up on compression stroke and the dash dies.

[Mhatayas]

I had the battery charger set to 20amps , it seemed to crank over fine but the display still spazzed out . So just yesterday I found 2 potential reasons why there were no spark . A blue wire coming from the stator that connects to the CDI , one of the connector pins was pushed back . I fixed it with some needlenose plyers , and the next thing I did was check for resistance between the coil and the plug cap with multimeter. One didn't have any resistance and the other did have resistance, so I put it back together, and wait a go ! Spark . Put a small bit of fuel in the piston just to hear it start up . I now drained the gas as there was water in there ,next I'm gonna clean the carb up before I actually take it for a run ! 

[Gwbarm]

Which one had no resistance, primary should have very little maybe.3 and secondary should be between 6 and 10. 

[Mech]

Good work finding the pushed back pin..

Time after time it's the wires not the electronic bits.. or Switches.. That flickering could be a key switch, or perhaps the kill switch, with dirty contacts. I'm pretty sure the flickering will be because the voltage to the gauge is dropping below the about 5volts the internals of the gauge usually work on.

[Mhatayas]

On 4/21/2024 at 11:15 PM, Mech said:

Good work finding the pushed back pin..

Time after time it's the wires not the electronic bits.. or Switches.. That flickering could be a key switch, or perhaps the kill switch, with dirty contacts. I'm pretty sure the flickering will be because the voltage to the gauge is dropping below the about 5volts the internals of the gauge usually work on.

Thanks .... So he got a new battery for it , and I had it running great except when I pressed the throttle it would big out and die. I ended up cleaning the carb and then it ran perfectly after that , I revved it up half a dozen times and then shut it off with the key to finish putting it back together for a test run . When I went to start it back up ... NOTHING.... I immediately checked to see if there was any spark and no there wasn't... So I'm back to square one again ...

 

I tried combinations of coils plugs plug caps and wires ... Nothing worked. 

 

Im going to have to go from the stator up to coil again with the multimeter... Gahhhh 

 

Oh, there's a few wires with the insulation off them , I wiggled them and moved them around to see if there is any spark .. but none still. 

 

 I don't know how it just went from sparking fine to nothing just like that . 

On 4/21/2024 at 10:58 PM, Gwbarm said:

Which one had no resistance, primary should have very little maybe.3 and secondary should be between 6 and 10. 

Thanks , and I'm not quite sure now thinking back on it . Also thought I'd have the darn thing going by now! But back to square one again. No spark again 

[Mech]

You used the key !  The key switch has dirty contacts or lost movement in it's mechanism.

[Mhatayas]

50 minutes ago, Mech said:

You used the key !  The key switch has dirty contacts or lost movement in it's mechanism.

Just went out and tried , cleaned the contacts , and even tried connecting the two wires together, cranked over but still no spark , darn it 

[Mech]

Ha.. Ok. Good man.

[Mech]

Well the standard procedure is check there is resistance through the cdi charge windings and the cdi trigger windings down on the stator plug, then crank it over and check there is some voltage produced at the charge pins and a momentary voltage at the trigger pins on the plug. You need a good spec digital gauge to detect the momentary trigger voltage, but an analogue gauge the needle flickers and is easy to see. , If there is voltage in both windings then we check they are getting to the cdi unit.

If there are those two voltages, and perhaps a 12v feed if needed, plus earth and a disconnected kill or a connected kill in some cases, then, if everything is ok, the spark should be very reliable. I would be suspecting the switches or the wiring. There are things that can go wrong in the engine though, like flakes of metal, or metal dust build up, that can short out the magnetic field between the magnets in the flywheel and the winding cores. If it's a flake of steel it can move and intermittently kill the trigger coil's output. I'd check for voltages out of those two windings, then look carefully at the wiring again.. short perhaps to frame ?

Oh, and is the dash still flashing ?

[Mhatayas]

28 minutes ago, Mech said:

Well the standard procedure is check there is resistance through the cdi charge windings and the cdi trigger windings down on the stator plug, then crank it over and check there is some voltage produced at the charge pins and a momentary voltage at the trigger pins on the plug. You need a good spec digital gauge to detect the momentary trigger voltage, but an analogue gauge the needle flickers and is easy to see. , If there is voltage in both windings then we check they are getting to the cdi unit.

If there are those two voltages, and perhaps a 12v feed if needed, plus earth and a disconnected kill or a connected kill in some cases, then, if everything is ok, the spark should be very reliable. I would be suspecting the switches or the wiring. There are things that can go wrong in the engine though, like flakes of metal, or metal dust build up, that can short out the magnetic field between the magnets in the flywheel and the winding cores. If it's a flake of steel it can move and intermittently kill the trigger coil's output. I'd check for voltages out of those two windings, then look carefully at the wiring again.. short perhaps to frame ?

Oh, and is the dash still flashing ?

Dash still flashing from 9to 0, but now it stops at 0 ! Thanks for this info. Tommorow I'll try to have another look at it and figure it out , again! Possible there is a shorted wire somewhere. Notable that once I got it running good and turned it off , I then proceeded to put everything back in its place and plastics and seat on etc... I put the CDI box back where it belongs. Maybe there is a shorted wire somewhere in around there . I'll check though and get my multimeter out for the rest of it ... 

[Gwbarm]

That sounds like a good plan, hopefully it is a shorted wire. They are sometimes hard to find, you may try feeding voltage directly in to the unit and see if it works then, that might give you an idea of where to start looking.