lost spark

[lilvina00]

quad was running great then started cutting out, backfired a time or two then couldnt get it started. cleaned the stator and flywheel changed plugs of course. where do I look now? cdi or coil or what

[riding4fun]

Check both ends of the spark plug wire to make sure they are screwed in tight.

[lilvina00]

done more than that, while I was waiting for a reply i robbed a coil off of his polaris 90 and tried it. still nothing. is there a way to test the cdi, key switch, and slide on off switch. thinking that is the only things left

[tyler70t]

When I lost spark, we changed the stator and all was fixed, of course we ran a lot of tests prior to changing it. Also, check your kill switch and all the wires related to it.....just a thought....Jeff

[lilvina00]

Thanks for the info. looked at all the wires, couldnt find anything wrong with them. thinking cdi or stator. some times you can kick it and it will get fire but not long enough to start, then you may kick it 20 or 30 more times before it will do it again

[tyler70t]

That's exactly what ours did when the stator went.

[raidernut]

99% of the time its the stator

Check your stator by using an ohm meter and follow these directions.

Tests to try if you have no spark or if your charging system is bad.

Preliminary test >>> This will not work on the Polaris and may not work on the Viper. If You Have either Proceed to the Stator test listed below.

1. Locate the CDI and unplug the connector for the black wire with the white stripe (or white wire with black stripe).
Test for spark. If no spark, leave it unpluged and proceed with test.

2. On the CDI, unplug the red wire with white stripe (could also be white wire with red stripe) AND the Black wire with white stripe (could be white wire with black stripe).

3. Locate the wires that come from the stator on the engine (right front top of engine. This harness is about 10" long can covered with a black tubing).
Connect the CDI red wire with white stripe (could also be white wire with red stripe) directly to the matching stator wire. Connect the CDI Black wire with white stripe (could be white wire with black stripe) directly to the stator wire.

Test for spark.

If no spark, you have a problem with the CDI, Stator or COIL. You have eliminated the AVT wire harness as the cause.


The stator tests as follows:

1. YOU MUST USE A DIGITAL OHM METER!!!
2. On the stator the ohm reading between the red wire with white stripe (could also be white wire with red stripe) AND the Black wire with white stripe (could be white wire with black stripe) should be about 1284 ohms for the ETON style (3 bolt fan) stators and 689 ohms for the Kasea, LRX and DRR (4 bolt fan) stators.
3. The red wire with white stripe (could also be white wire with red stripe) to ground should be about 447 ohms for the ETON style (3 bolt fan) stators and 112.7 ohms for the Kasea, LRX and DRR (4 bolt fan) stators.
4. The Black wire with white stripe (could be white wire with black stripe) to ground should be about 837 ohms for the ETON style (3 bolt fan) stators and 576 ohms for the Kasea, LRX and DRR (4 bolt fan) stators.
5. From the plastic connector with the three wires, confirm that the black lead has 0 resistance between the lead and the frame of the atv. That is the ground lead. Any noted resistance in the ground system means the ground is BAD. We recommend always adding a wire between the engine and the frame for a better ground.

NOTE That the total ohms for #3 and #4 are the same as the ohms in #2. That is because we but the resistance of the two coils in series and added the ohms.

IF YOU DO NOT GET THESE READINGS your stator is BAD.

COILS:

1. There are two resistances in coils. Eton vs. Kasea.
2. The Eton should measure about 9.24k ohms checking between the high voltage lead (no boot) and the coil ground.
3. The Eton coil should also read about .5 ohms between the coil input and coil ground. Kasea reads about .3 ohms. Don't switch them because you can burn out your CDI and stator.

Your typical plug cap is a resistor cap and it should read about 5k ohms. A great replacement cap is the NGK TB05EMA.

If your stator, coil and engine kill wiring tests OK, you simply need a new CDI. I will not list out CDI test procedures since you have concluded your CDI is bad and because if you test the CDI improperly, you will damage the unit.


If you want to check the charging feature of the stator:

(We assume that you have confirmed that the in-line fuse near the battery is good and that your battery is in good shape.)
1. Locate the 3 wire plastic plug from the stator. One wire is the black ground and the other two are the charging system.
2. The Orange wire with red stripe to ground should read about .4 ~ .5 ohms on the Eton and the same on the Kasea style.
3. The White wire to ground should read about .5 ohms on the Eton and .3 ~.5 on the Kasea style.

NOTE: You cannot interchange the Eton for the Kasea stator without the matching flywheel and there are two crank tapers that you will find. The Kasea style has a substantially higher voltage output for lighting.

[redonkulousruntsracing]

I ran into this same problem this weekend with a 90. The kid parked next to me went out and practice and then pulled back into the pits and pulled his tether. Every thing was fine. He goes to start for Moto 1, no spark, kick and kick and kick, no spark. Fiddle withall wires, check tether switch everythink ok, no spark. After he missed the 1st moto. I pulled off water pump, to check every thing in there, cleaned the pick-up and magnet. It started right up, I rode it around the pits and it ran fine. Let it sit for 10 min, went to start it again, it fired then quit, did that 2 or 3 times, then back to no spark.

TG wiil those checks you posted apply to an 07 Apex 90? That sound's like where they guy I helped out needs to go next.

[marsrace2]

I fought with this same issue recently only to find out it was the tether switch. Check the nob where you attatch the tether to and make sure that when you push the tether in it is actually pulling the nob out. I found out with ours the nob can turn out and you just need to turn that nob back in so that it actually pulls out when you plug the tether cord into it.

[redonkulousruntsracing]

yea, we just bypassed it, to rule it out.

[marsrace2]

alright, good luck hope you get it figured out.

[lilvina00]

just got the spark problem fixed. changed the coil, nothing, changed stator nothing, grounded the frame nothing, checked the switches including the kill, nothing. changed the CDI box and started on the first kick. thanks to everyone that helped I hope this info will help the next person.

Originally posted by sickairseth
I ran into this same problem this weekend with a 90. The kid parked next to me went out and practice and then pulled back into the pits and pulled his tether. Every thing was fine. He goes to start for Moto 1, no spark, kick and kick and kick, no spark. Fiddle withall wires, check tether switch everythink ok, no spark. After he missed the 1st moto. I pulled off water pump, to check every thing in there, cleaned the pick-up and magnet. It started right up, I rode it around the pits and it ran fine. Let it sit for 10 min, went to start it again, it fired then quit, did that 2 or 3 times, then back to no spark.

TG wiil those checks you posted apply to an 07 Apex 90? That sound's like where they guy I helped out needs to go next.

Yes it should.