Yamaha bear tracker 250 kill switch bypass

JackThompson899 · July 17, 2022

Hey guys,

I have lurked here for about 7 years (thanks for the yearly birthday wishes!)

I posted 7 years ago that we bought a used Yamaha Bear tracker.. and we have had many adventures since then, but half of them have been repair “Adventures”

It stopped starting (Even pull start) last year and I tried the basics (Spark plug, clean carb etc)

I took it into a shop and they did EVERYTHING to get it to spark. New coil, replaced the entire handlebar cluster (Switches, coil, starter switch, neutral safety, and finally replaced the entire wiring harness.)

It simply won’t even try to start. Pulling the pull cord doesn’t start it. After paying for their time and efforts (Over $1000) I dragged it home dead... This shop only “Fixes” things using OEM factory parts and won’t “Jury rig” anything... so if there was a creative way to bypass the entire thing to just start it, they couldn’t really discuss it.

I did ask the mechanic when I was loading it up “What would YOU do if this was your ATV at home and you had these issues?”

He said he experimented with bypassing the kill switched and it turned over. I didn’t think to ask HOW he bypassed the kill switch, but it sounds like that’s my culprit!

So how do I bypass the kill switch on a 2003 Yamaha Bear Tracker 250? Or, is there a way to Hotwire it so I can start it without the starter button (In case that’s the issue, even though it shouldn’t be since the entire handlebar cluster is new.... it seems haunted at this point!

**Mech** · July 17, 2022

Well as a mechanic I gotta say that is appalling ! That "replace everything" policy is the modern version of professional in the major part of the service industry. But they aren't competent..and they don't care they are incompetent, they charge anyway. And all those parts are what makes them profit, so why wouldn't they. If they admit fault, it costs them, if they bullshit and "justify" the necessity for all those parts, they get to charge you and make their wages, and profit on parts. If you have something like a small claims court, mediation process you can take them to.. I think you would have a very good case.. Did you get your old parts back ? Under these circumstances it should be standard practice for them to show them to you and offer them to you before they dump them. With or without the old parts, whether they were needed or not, they only did half the job and shouldn't have charged unless the job was done. They should have kept going and replaced/repaired the fault, then they can charge for their expertise. Grrr..

Anyway... I don't have a manual for that bike but I suspect the cdi runs off the stator, and/but needs a twelve volt feed into the cdi unit to turn it on.

If you get a manual and follow the diagnostic steps(as a mechanic should do), it tells you how to test switches, and cdi units, and stators and trigger coils.. I think though that to eliminate wiring problems(because there are diodes in the wiring), you should do as you are suggesting, and hotwire the cdi unit as a first step, then worry about the electric start. If you look in a genuine yamaha pdf manual, in the ignition diagnostic section it will have a small wiring diagram of the ignition circuit I think, the bit's of wiring being used for the ignition will be highlighted, use that diagram and if it does show a 12 volt feed into the cdi, then do that, and check it's earth, and then there should be a spark when you pull it over by hand.

If there is no spark then, with only the wiring from stator to cdi being used, it's either cdi(yeah I know, it's new), or coil, sparkplug, stator or trigger coi, or wiring.. The manual explains how to test the stator and trigger coil with a multimeter. That's the simplest test to do and it's not been mentioned.. Perhaps they were really certain about their ability to test a stator and so didn't think it was in question, or... they didn't check that..

In fact... if the wiring really is brand new, it's probably only going to be either the cdi or the stator.. So test the stator first, then if that and the trigger coil which is in the stator both have good readings on the gauge, try hot wiring the 12 volt into the cdi if it's meant to have a 12 volt feed, and test for spark while pulling it over.

JackThompson899 · July 18, 2022

3 hours ago, Mech said:

Well as a mechanic I gotta say that is appalling ! That "replace everything" policy is the modern version of professional in the major part of the service industry. But they aren't competent..and they don't care they are incompetent, they charge anyway. And all those parts are what makes them profit, so why wouldn't they. If they admit fault, it costs them, if they bullshit and "justify" the necessity for all those parts, they get to charge you and make their wages, and profit on parts. If you have something like a small claims court, mediation process you can take them to.. I think you would have a very good case.. Did you get your old parts back ? Under these circumstances it should be standard practice for them to show them to you and offer them to you before they dump them. With or without the old parts, whether they were needed or not, they only did half the job and shouldn't have charged unless the job was done. They should have kept going and replaced/repaired the fault, then they can charge for their expertise. Grrr..

Anyway... I don't have a manual for that bike but I suspect the cdi runs off the stator, and/but needs a twelve volt feed into the cdi unit to turn it on.

If you get a manual and follow the diagnostic steps(as a mechanic should do), it tells you how to test switches, and cdi units, and stators and trigger coils.. I think though that to eliminate wiring problems(because there are diodes in the wiring), you should do as you are suggesting, and hotwire the cdi unit as a first step, then worry about the electric start. If you look in a genuine yamaha pdf manual, in the ignition diagnostic section it will have a small wiring diagram of the ignition circuit I think, the bit's of wiring being used for the ignition will be highlighted, use that diagram and if it does show a 12 volt feed into the cdi, then do that, and check it's earth, and then there should be a spark when you pull it over by hand.

If there is no spark then, with only the wiring from stator to cdi being used, it's either cdi(yeah I know, it's new), or coil, sparkplug, stator or trigger coi, or wiring.. The manual explains how to test the stator and trigger coil with a multimeter. That's the simplest test to do and it's not been mentioned.. Perhaps they were really certain about their ability to test a stator and so didn't think it was in question, or... they didn't check that..

In fact... if the wiring really is brand new, it's probably only going to be either the cdi or the stator.. So test the stator first, then if that and the trigger coil which is in the stator both have good readings on the gauge, try hot wiring the 12 volt into the cdi if it's meant to have a 12 volt feed, and test for spark while pulling it over.

Thanks for the quick reply! I agree, if you can’t troubleshoot outside new parts you aren’t much of a mechanic. They have done well with cleaning the carbs on my generators though…

I’ll see if I can find the manual, and those tests sound like exactly what I need to do.

I’ll report back with my results!

**Mech** · July 18, 2022

There's likely a manual in here.. up top click "downloads", then atv repair manuals, choose yamaha and scoll through for your model..

**Mech** · July 18, 2022

So I'm not real familiar with yamaha, and their versions, but I just downloaded one manual(there are two there), and it shows the cdi as having an earth wire to kill it, and a 12 volt feed in only while it's cranking. That's to assist in easy starting, but the cdi should still spark without it. The ignition timing probably gets retarded by that 12 feed is all. Someone here might know otherwise about yamaha, but that's a common vehicle strategy.

I'd disconnect the wires from stator to regulator down at the engine while I was checking the ignition system, just to be sure the regulator wasn't causing a problem. Then, if you disconnect the two single wires from the cdi(L/W + B/W), and plug in the stator plug at the engine and at the cdi, it should send a high voltage high current pulse of power out to the ignition coil when you pull it over. The cdi output is dangerous so don't get zapped by it. The coil needs to be a special low impedence one made for cdi ignitions. Cdi suitable ignition coils are everywhere these days and cheap. The book tells how to check them. The easiest way to check the cdi once you are sure the stator and tigger coil are good is to use a known good ignition coil..

Th cdi unit, and the ignition coil, the regulator, and the engine, all have to be grounded, together and to the frame. It might pay to check all those points where the earth wires connect are clean.

**Ajmboy** · July 21, 2022

I only see one for 2001, might be the same.

Stilkikn · August 14, 2022

Yamaha apparently made some changes in the starter circuits sometime in the early 2000s.
I'm not sure about a 2003 model but my 2002 Bear Tracker doesn't use a ground wire in the kill switch. When it is ON (or RUN on some models) then battery voltage is continuously sent to CDI. But when kill switch is OFF then that voltage simply doesn't reach the CDI, no grounding takes place, just a voltage dis-connect. The kill switch on mine also sends battery power to the starting circuit cutoff relay, not to be confused with the starter relay itself. On my 2002 the starter won't even engage if the kill switch is turned off. Hope I haven't confused the issue further but important to know that there are two types of kill switches out there. Also, you didn't mention the stator or CDI as parts that the dealer replaced. Not sure why they wouldn't but if they didn't and you're not sure about condition of either of these, there are Chinese replacements all over Ebay for a fraction of OEM parts. Some folks report having bad luck with them but I recently replaced the stator on my Bear Tracker with a Chinese one for less than 30 bucks and it works just as it should. OEM stator is in the 300 to 400 dollar range...

JackThompson899 · August 14, 2022

3 minutes ago, Stilkikn said:

Yamaha apparently made some changes in the starter circuits sometime in the early 2000s.
I'm not sure about a 2003 model but my 2002 Bear Tracker doesn't use a ground wire in the kill switch. When it is ON (or RUN on some models) then battery voltage is continuously sent to CDI. But when kill switch is OFF then that voltage simply doesn't reach the CDI, no grounding takes place, just a voltage dis-connect. The kill switch on mine also sends battery power to the starting circuit cutoff relay, not to be confused with the starter relay itself. On my 2002 the starter won't even engage if the kill switch is turned off. Hope I haven't confused the issue further but important to know that there are two types of kill switches out there. Also, you didn't mention the stator or CDI as parts that the dealer replaced. Not sure why they wouldn't but if they didn't and you're not sure about condition of either of these, there are Chinese replacements all over Ebay for a fraction of OEM parts. Some folks report having bad luck with them but I recently replaced the stator on my Bear Tracker with a Chinese one for less than 30 bucks and it works just as it should. OEM stator is in the 300 to 400 dollar range...

hey! Very interesting idea here! I am 99% sure the CdI was also replaced (stator I think as well.. it’s been a while.

so, for the ground wire on the kill switch. Can I bypass that? (Hardwire) if so… is there a dead simple instruction you might have? (Like, connect the green/white cable coming off the kill switch directly to the chassis. Or something?

id love to test that theory.

**Mech** · August 14, 2022

That does sound like the problem.. What Stilkikn says..

Stilkikn · August 15, 2022

Here is the ignition circuit on my 2002. I don't know if your 2003 is the same but will be very similar. Might give you a starting point if you haven't found a better wiring reference yet. You're asking how to bypass to ground wire on the kill switch but as I stated above, apparently there are two different kill switch circuits one with a ground wire and one without, mine has no ground wire in the kill switch, just basically a dis-connect switch from the hot wire off the battery so I can't help you on that. If you know for sure which system you have and have the correct wiring diagram for it then post a pic of it and I'm pretty confident someone here will be able to help you figure it out.