Ok I just bought a used 90cc baja quad and cant get it to run. I have been tracing wires and cant believe how bad the harness is on this. Anyways I am having a problem getting spark. When I crank it over I have 16v at the plug that slowly decreases but no spark. Also something I found was that without the ground wire on the ignition coil I dont have anything. From the cdi the wire going to the coil (black with yellow) has the same 16v but only with the ground wire disconnected from the coil otherwise almost nothing .010v or so. From the magneto the blue and yellow wire has .300v. I also noticed that if I ground the wires straight to the battery instead of the bare frame or a ground wire that i get more voltage. Any ideas of what I should be checking? I have a new cdi so I dont believe that is the problem and I have already spliced the emergency stop button together. I am so confused now that I dont even know what to check anymore. Thank you very much for your help

 

Something like this is difficult to diagnose over the net. You say the wiring is crappy as in all corroded up or what? If so make sure all connections are good. Have you had the left side cover off and had a look at the magneto? Maybe the quad was in deep water and it got all wet inside and now is all rusty in there.

Do you have a wiring diagram for it? There is one in the owners manual. That may help you out some. Also the engine is a copy of an old Honda engine. The Clymer repair manual - Honda: 50-110Cc Ohc Singles 1965-1999 would cover it also. Plus I believe you can call baja at 888-863-BAJA (2252) for service manual or check there website at http://www.bajamotorsports.net/index.htm


I have never played around with the ignition system on these little quads.

 

NO the harness is not all rusted it is just put together crappy. i will pull the cover today on the magneto and check that out and yes I have seen the wiring diagram but it is different than the wiring on my baja 90. Thank you

 

Just wondering shouldnt the ignition coil be jumping the volts up to more than 16v. I am wondering if maybe the coil is bad and not boosting up the volts to make a spark. Thank you

 

<div class="FTQUOTE"><begin quote>Originally posted by: WisdomRacer

NO the harness is not all rusted it is just put together crappy. i will pull the cover today on the magneto and check that out and yes I have seen the wiring diagram but it is different than the wiring on my baja 90. Thank you</end quote></div>


What year is yours? Does it have the speed/RPM limiter on the back or is it the newer kind built into the CDI??

I have a 2005 and the wires you discribed matched my wiring diagram.

 

I have a 2004 but ya the rev limiter I believe is built into the cdi. The cdi has a 4 prong and 2 prong connector.

 

Ok I looked at the magneto and it looks brand new still. Just a question but on the 4 prong connector going to your cdi do you only have 3 wires. I noticed on most wiring guides that the cdi has 4 wires. Where does cdi get the power to make a good spark. I see that one wire is ground, one goes from the magneto, and the other goes straight to the ignition coil. I have two of these that both dont work and have tried switching basically every electrical part except the cdi (i only have one right) and the magneto b/c it still looks good. thank you very much for the help so far

 

<div class="FTQUOTE"><begin quote>Originally posted by: WisdomRacer

I have a 2004 but ya the rev limiter I believe is built into the cdi. The cdi has a 4 prong and 2 prong connector.</end quote></div>



Well if its 2004 I would think it has the rev limiter on back left side bolted onto the frame under the fender.. Its a square plastic box with one bolt bolting it to the frame.

 

<div class="FTQUOTE"><begin quote>Originally posted by: WisdomRacer

Ok I looked at the magneto and it looks brand new still. Just a question but on the 4 prong connector going to your cdi do you only have 3 wires. I noticed on most wiring guides that the cdi has 4 wires. Where does cdi get the power to make a good spark. I see that one wire is ground, one goes from the magneto, and the other goes straight to the ignition coil. I have two of these that both dont work and have tried switching basically every electrical part except the cdi (i only have one right) and the magneto b/c it still looks good. thank you very much for the help so far</end quote></div>


I'll take a look at mine. I'm sure there is a procedure to a diagnoses for a no spark on an ATv. NO different then in an automotive application which I've done 100's of. Over time (on cars) you just get to know what typically is faulity on certain brands and models. It would be no diff. on these little atvs.

As you mentioned before check the wire harness connectors for continuity. On my 110 atv I noticed they were lower quality connectors. The pin connectors were not top notch and over time made a poor connection for the start switch. I ended up just bypassing it and problem solved. Never had a problem with no spark though.

Thats why on the Jet I just got I put dieletric grease on the harness connectors.

I have some HOnda ATV service manuals i the shop. I'll take a look at and see it they relate to this ignition system.

Hey look on the bright side.....once you get it working you'll know the ignition system on these things like the back of your hand!!

I'm sure someone out there knows the "flow chart" procedure in diagnosing these little things with out wasting a bunch of time.

later

 

Oh trust me i basically do. I think I should give more info. This quad is basically brand new. It is a customer return to pep boys that I got for $50 so I have been going through it trying to get it to work. I actually got two for $100 that both need work. I was told all it needed was a CDI but after buying that I realized it was something more. I have spent atleast 8 hours just looking at the wiring diagram and prob 20 hours total on the quad. I am trying to get it working for my 10yr old sister but so far its a no go. You know what I am not sure where the emergency stop switch is now. I thought I knew which wires it was but now I dont think it is them. What color wires should they be. Also the black wire from the rectifier should be powered shouldnt it because mine is not? I noticed that I had to connect the black past the rectifer to a power wire to get the starter to work when I press the button. I am starting to think I may draw up a wiring diagram of what I have so far so hopefully someone can see what is wrong. Thank you for all the help so far though