OK this is my second 2nd kids 2 stroke quad. I've had a 01 polaris scrambler 90 since new and still runs great. I just picked up a lightly used but well neglected 05 viper 90 2 stroke with reverse with no spark. this is what I know and have done so far.

1. wire harness is all cut up with splices galore.

( purchased new harness and installed.)

2. stator had no voltage out of black/red wire or white/something ( trigger ).

(perched new stator tested it had 87 volts on black/red and trigger is .5 i think anyway I tested the stator on the Polaris and it sparked fine.)

3. cdi, I didn't know how to test it so I bought a new one still no spark.

I cant find any kill buttons or remote kills anywhere, am I missing something. the left hand brake switch works, the brake light comes on, the motor turns over but no spark. there are a lot of unused plugs on the main harness that don't go anywhere am I missing parts that it needs to run if so I hope someone can help.

thanks Dave

 

I think your missing a safety switch somwhere. I could be wrong.
Hopefully Lynn Edwards will chime in.

 

How many wires on your CDI?

Is this the viper 90 with 17 wires going to the CDI?

 

yes it is, the quad was not running when I got it. I replaced the wire harness and didnt find any safty switch or remote shut off.

thanks for any help

 

According to the Eton Viper 90R published wire diagram this quad has a CDI with a lot of wires, but many of them don't seem to have anything to do with the ignition system. It looks like they combined the transmission shift motor logic, transmission position indicator light circuitry, and ignition stuff all together in one module.

I have to say from the outset that I've never even seen one of these quads, but the published wiring diagram seems complete, makes logical sense, and is free of any obvious errors. All the following is based on Eton's wiring diagram, basic electronics, and similarities with many other quad brands...

Acording to the wiring diagram the CDI has 17 wires as follows:

Cyan/Yellow: Brakes Applied Signal Input
Gray: F/N/R Lamp Power Output
Purple: Neutral Lamp Drive Output (Ground to light up lamp)
Yellow: Forward Lamp Drive Output (Ground to light up lamp)
White: Reverse Lamp Drive Output (Ground to light up lamp)
Brown/Black: Shift Motor Power 1 Output
Brown/Blue: Shift Motor Power 2 Output
Green/White: Forward Gear Engaged Input
Blue/Red: Reverse Gear Engaged Input
Gray/Red: Neutral Input
Green/Red: Shift Drum
Brown: Ignition Switched/Fused 12 volts DC from battery
Black: Ground
Black/Red: AC Ignition Power Input
Brown/Yellow: Ignition trigger input signal from stator through many switches
White/Blue: Ignition Output from CDI to Ignition Coil Primary
Black/White: Kill Spark Input (ground enables spark, open kills spark)

Look at those wire colors and see if they agree with your harness colors. If there are any discrepancies, and post them back for analysis.

The Ignition stuff will involve the last 5 wires above certainly, and maybe it involves the last 6 wires.

Let's start with some basic resistance tests:

1) Unplug the CDI. Turn on the ignition, and set all kill switches into the "run" position. Use a meter set to measure resistance between the following pins in the wire harness at the CDI connector.

2) On the 2K ohm scale what is the resistance between the Black/Red wire and the Black wire? This measures the AC Ignition Power winding in the stator through the wiring harness.

3) On the same scale, measure the resistance of the Brown/Yellow wire to the Black Wire. What resistance do you measure? This measures the timing/trigger winding in the stator through the the remote control module, tether kill switch, and ignition switch.

4) On the same scale, measure the resistance of the Black/White wire to the black wire. What resistance do you measure? This is measuring the kill switch input signal to the CDI through the left handlebar On/Off switch.

5) GO to your lowest resistance scale (like 2 or 20 ohms). If you don't have that go to the 200 ohms scale. Measure the resistance of the White/Blue wire to the Black wire. What do you measure? This is measuring the Ingition Coil Primary winding through the wiring harness.

6) Finally, again using the lowest ohms scale you have, measure the resistance of the black wire to the negative battery post. What do you measure? This is measuring the connection between the CDI connector ground pin and the battery ground pin.

This is a start. If your readings are way off then we start here and find out why. If they look OK the the next step is to measure voltages while cranking the engine...

 

thanks, I will try this later today and repost what I find.

 

sorry it took so long but this is what I found. key on cdi box unpluged tested wire harness side.
ohm meter set at 4k, black/red wire to black = .0780

set at 4k brown/yellow to black = nothing, meter didnt move

set at 4k black/ white to black = .026

set at 400 scale white/blue to black = 2.1

400 scale black to battery post = 1.9


I hope this helps

 

My comments in blue:

 

thanks, here is the modle number of the meter, Techmaster ( DM-8400 ) A.W. Sperry.
I will recheck later today. O and I cant find any other tether or remote kill switches but the one on the left hand and the key.

 

ok retested with a different meter, much older non digital and non adj. reads 0 to 2k
black/ red to black = 1,000 ohms
brown/yellow to black = nothing
black/white to black = 4 ohms
white/blue to black = 3 ohms
black to battery post = 3 ohms

hope this sheds a little light