[kaptinkaveman]

1999 Foreman 450 ES, No spark, started to sputter and I shut it off, now she's dead.
Pulse Coil Resistance tested high 425 oms, peak cranking voltage low .1 to .3 vac
Replaced and now in spec 325 oms, .8 vac

Now intermittent spark, very erratic, some times sparks for 10 sec others no spark for 30 sec
Stator windings .3 oms, 6-8 vac wile cranking
Coil .15 oms Primary, 7koms with cap Secondary
All wires from CDI have less than 1 oms to their respective ends
battery voltage on B/W
Good ground through neutral switch
All connectors are clean with no bent prongs
Tried unplugging neutral switch and bypassing it to ground

I went so far as to put the CDI and Coil on my 98 TRX300EX, started and ran
then tried ones off the 300EX on the Foreman and intermittent spark


I am at a loss! Please help

Thanks

 

[mud99]

Welcome to the forums

we have several members that should be along to help with your question

 

[shadetree]

1999 Foreman 450 ES, No spark, started to sputter and I shut it off, now she's dead.
Pulse Coil Resistance tested high 425 oms, peak cranking voltage low .1 to .3 vac
Replaced and now in spec 325 oms, .8 vac

Now intermittent spark, very erratic, some times sparks for 10 sec others no spark for 30 sec
Stator windings .3 oms, 6-8 vac wile cranking
Coil .15 oms Primary, 7koms with cap Secondary
All wires from CDI have less than 1 oms to their respective ends
battery voltage on B/W
Good ground through neutral switch
All connectors are clean with no bent prongs
Tried unplugging neutral switch and bypassing it to ground

I went so far as to put the CDI and Coil on my 98 TRX300EX, started and ran
then tried ones off the 300EX on the Foreman and intermittent spark


I am at a loss! Please help

Thanks

look's like your stator is weak to me..i'm no elec. by any means..but..i do know how these bikes run..or shall i say..what it takes to make them run..not sure if you know this or not..but..your stator has two sides to it..one side charges ..sends ac voltage to reg/rec..this reg/rec converts this power to dc..which powers your lights ..and recharges your battery. now..the other side of your stator..sends power to the c.d.i....as all this is going on..the flywheel is timed so when the metal piece on it get's to the pick up coil..this tells the c.d.i when you release the votage to the spark plug coil..then fire the spark plug..sooo..bottom line is..if your stator isn't putting out enough voltage..then your c.d.i can't fire the plug..this is probally why your c.d.i runs when you put it on the 300ex.

 

[kaptinkaveman]

I double checked the stator output and compared it to the 300EX and they are identical. 6-7 vac wile cranking. And the AC feed line from the stator to the CDI has .2 oms from CDI plug to Stator plug.

POOP!

 

[shadetree]

what about your reg/rec ..did you run a check on it ?.

 

[shadetree]

also..you could have a weak battery...make sure your battery is fully charged..this is why i asked if you checked your reg/rec..if it's bad..some bikes won't run very good or at all.

 

[kaptinkaveman]

Battery load tests 200CCa, and I have another bat piggy backed to keep cranking speed up. Also have a 5amp charger hooked up. I did a diode test to the reg/rec and it appears good. Tried unplugging reg/rec and no luck!

 

[shadetree]

Battery load tests 200CCa, and I have another bat piggy backed to keep cranking speed up. Also have a 5amp charger hooked up. I did a diode test to the reg/rec and it appears good. Tried unplugging reg/rec and no luck!

if you can find another c.d.i from the same year and make..i would try that. i find it hard to believe you took the c.d.i out of that bike..and had it run the 300ex..most c.d.i's won't inter change from make and model..i'm thinking it's your c.d.i.

 

[shadetree]

I double checked the stator output and compared it to the 300EX and they are identical. 6-7 vac wile cranking. And the AC feed line from the stator to the CDI has .2 oms from CDI plug to Stator plug.

POOP!

on a side note, you can not compare one stator from the 450 to the 300ex..they all are not the same..each bike requires different voltage to the c.d.i..simply because c.d.i's are all not the same...what does your service manual say your stator should be ?

 

[kaptinkaveman]

The CDI boxes probably have different ignition curves but they do interchange as far as checking a component. Would I run it around on my other wheeler not knowing what the timing is doing, no. The stator resistance and cranking voltage specs overlap each other. Total amperage output the foreman has more but per Honda specs they are close enough to compare AC output wile cranking and resistance.

 

[shadetree]

The CDI boxes probably have different ignition curves but they do interchange as far as checking a component. Would I run it around on my other wheeler not knowing what the timing is doing, no. The stator resistance and cranking voltage specs overlap each other. Total amperage output the foreman has more but per Honda specs they are close enough to compare AC output wile cranking and resistance.

all i know is..your power starts at your stator and pulse generator,if both of these are working..and your c.d.i is good..and your spark plug coil is good..and you have a good spark plug ( i said spark plug )..because i was working on a bike the other day.it wouldn't run or spark on one plug..changed plug..and it fired right off...and all your switches with power are good..then you should get a good spark..if you don't..then one of these parts is bad, or you got a bad connection in your wire harness somewhere.

 

[kaptinkaveman]

I'm going to try a new stator. This is the only component that I could not swap and test.

Wish me luck!!

 

[Redracer]

Kaptinkaveman!!!!! Good luck! LOL you will get it no problem

 

[kaptinkaveman]

I got a chance to install a new Stator today. Now I consistently have spark when I let off of the start button. And if I let off the starter and then push it again just after it starts to spark it will continue to and may for the next 3 or 4 times the starter is spun up. I tried running separate grounds for the Ignition Module and Ignition coil, and same thing. Then tried bypassing the kill switch. Just butt crimping the two wires together, same thing. Again I swapped out the Module from a 300ex again and it made the ex run and same spark condition with the 450. I have been on line searching all over and found quite a few cases of the reg/rec killing the stator. But none referring to my kind of problem. I'm running out of hair to pull out!!

I'll hit it again next week. Any thoughts would be greatly appreciated!!

 

[shadetree]

I got a chance to install a new Stator today. Now I consistently have spark when I let off of the start button. And if I let off the starter and then push it again just after it starts to spark it will continue to and may for the next 3 or 4 times the starter is spun up. I tried running separate grounds for the Ignition Module and Ignition coil, and same thing. Then tried bypassing the kill switch. Just butt crimping the two wires together, same thing. Again I swapped out the Module from a 300ex again and it made the ex run and same spark condition with the 450. I have been on line searching all over and found quite a few cases of the reg/rec killing the stator. But none referring to my kind of problem. I'm running out of hair to pull out!!

I'll hit it again next week. Any thoughts would be greatly appreciated!!

kapt..just had the so called intermitent spark problem on a '97 trx300fw today..well..we put my ' 96 c.d.i box on the '97..and it would only spark when we let off the start button..sooooo..we've had this problem before..and found out it was the c.d.i..changed them out with a different one..sure enough it cranked and ran..nowwwww..here comes the tricky part..i went to my local honda shop..where one of my best buddies works..and has about 20 or more years as a honda maechanic there..he said honda had a real bad problem with the c.d.i boxes on the years of ' 95, '96,'97, and ' 98 models..the c.d.i's were defective for this very reason..well..after talking to him..he said when i put my working c.d.i on the ' 97..and it would only spark after letting off the start button..he said go back..put the spark plug in the ' 97..and crank it over ..and it will start and run..we'll..i thought to myself there for a min..and said..ok..but..how the heck does it work..in other words..how does the c.d.i know when to fire at TDC ??????..A HE SAID..THEY DON'T..IT'S JUST A GAMBLE..bottom line..replace the c.d.i.

 

[Helmut]

My guess is the CDI too. Usually when they spark once after you let off the starter button, that's the problem.

 

[kaptinkaveman]

I'm very hesitant to replace cdi. The cdi out of the 99 450es starts and runs my other wheeler. I did not ride the 98 300ex with this cdi but have idled it several times. On the same note the ex cdi behaves the same in the 450es. Not just one little spark, but just like you would expect to see if you were pulling it over by hand. Then to make things a little more neat if you hit the button again wile it is still sparking it will continue to do so until the starter button is released. Most of the time it will spark like normal for two or three pushes of the starter button after that. Then back to the sparking without the button pushed. I am gonna put the tank back on it and the plug in and see what happens.

Yes I have ridden the 300ex since swapping things around, with the correct cdi. I am at my budget limit for parts for this thing until spring. The only thing that has improved my situation so far was the new stator. Here comes another bald spot!!

 

[shadetree]

I'm very hesitant to replace cdi. The cdi out of the 99 450es starts and runs my other wheeler. I did not ride the 98 300ex with this cdi but have idled it several times. On the same note the ex cdi behaves the same in the 450es. Not just one little spark, but just like you would expect to see if you were pulling it over by hand. Then to make things a little more neat if you hit the button again wile it is still sparking it will continue to do so until the starter button is released. Most of the time it will spark like normal for two or three pushes of the starter button after that. Then back to the sparking without the button pushed. I am gonna put the tank back on it and the plug in and see what happens.

Yes I have ridden the 300ex since swapping things around, with the correct cdi. I am at my budget limit for parts for this thing until spring. The only thing that has improved my situation so far was the new stator. Here comes another bald spot!!

i still say the c.d.i..what ever you find out..let us know...my money is on the c.d.i.

 

[kaptinkaveman]

Well I gave her some fuel and she will start after cranking on and off. Idles great and revs ok. But @ exactly 4000 rpms it dies. This happens every time. You guys talked me into it. A new CDI is on the way.

 

[kaptinkaveman]

No change!!!!!!!! New CDI did nothing!!!! Every part of the ignition system is new WTF? I am totally lost!!!! DV voltage @ the battery never goes above 14 wile reving and once idling sits @ 12.8-13. Again WTF?

At the onset of this nothing tested out of honda spec. No weird voltage drops or high resistance in the wiring.

What am I missing?