[weld_addict]

Ok i have replaced the wiring harness on a 450 i just purchased and have been trouble shooting it due to no spark. i recently installed a cdi off of a running honda and get an occassional strong blue spark but only when i flip the kill switch on and off, but here is the thing i have thoroughly checked the killswitch with an ohm meter and it checks out perfect any advice...thanks in advance

 

[weld_addict]

Does anyone have a pdf manual?

 

[retro]

You can find a factory service manual in the thread at the top of the manuals forum:

https://www.hondaatvforums.net/foru...nual-help/50817-service-manual-downloads.html

Its quite good... you should find everything you'll need to know in the switches section and the ignition section. The wiring diagram is near the back if you need it.

Are you cranking the motor over using the electric starter? If so, do you see a single spark when you release the starter button?

Let us know how it goes if you can.

 

[fishfiles]

When you got another wiring harness , did you get the one for your year and model new OEM ? or Did you buy used ---the wiring harness for a 2004 450 FM only fits 2002-2004 FM's , a 2002-2004 450 ES would be different , as would a 98-2001 ES or FM/S

 

[weld_addict]

I'm cranking it by pull cord or by jumping the solenoid and i will only get spark if i swith the kill switch to the off or run position while cranking. Have checked the kill switch 3 different times with a meter and it checks out perfectly which has me stumped. it has a nice blue ark and looks plenty strong enough to run the bike though that can be decieving i do not think it is the stator or components because i also have checked it several times i just dont know why messing with the kill switch will make it fire when the kill switch is checking ok maybe the cdi is bad and the wire that runs from killswitch to the cdi is tricking it somehow to fire when it is toggled on and off. anymore ideas

 

[weld_addict]

bought one used but was for the same year and model and looks to be in great shape

 

[fishfiles]

bought one used but was for the same year and model and looks to be in great shape

Who told you it was the right year and model ? e-bay or amazon sellers just don't know and sometimes lie to get a sale , someone like Powersportsnation I would trust

I think there are 4 different wiring harnesses for the 450's from 98-2004 when you add in foot shift and ES , makes for some mistakes

 

[retro]

It sounds like you don't have it back together yet, or missing some parts...? Why aren't you using the starter button?

What else is incomplete/cobbled on the bike..? Are 100% genuine Honda parts on the bike or have you (or someone else) swapped in china knockoffs?

I don't mean to sound like a jerk, but it doesn't sound like that bike is ready to run yet.

 

[fishfiles]

Why was the wring harness changed ? Was there a problem that stated all this ? It might help to know to figure what is wrong ? Melted wires ? Someone butchered the wires ? Did you use any of the electrical parts that could have been attached to the new harness ?

 

[fishfiles]

the 96 300 cdi made by Phillips had a kind of similar spark problem , when they went bad , they wouldn't spark when you pressed the starter button , as soon as you let go of the button it would spark till the engine stopped turning , if the engine was in tune then it would start on that split second of spark , if you missed it , you could spin it till you was blue in the face it wouldn't spark , till the split second you let off the button

 

[weld_addict]

Thanks everyone for the comments i changed the cdi and it fires like a champ as for the wiring harness it was butchered by the previous owner so i replaced it. The starter solenoids seems to be bad i really have not tried to fix it up untill this point because i wanted to get it firing correctly first. There is a blue wire and a yellow wire running to it i get full battery voltage on the yellow wire while pressing start button so i'm assuming it is bad will know more when i check the manual. When i bought the four wheeler i didnt know any background knowledge on what was wrong with it but it seems to run fine i do get a small top end knows when i throttle hard and let off of it but cannot hear it at idle or almost full throttle. Could it possibly need valve adjustment it does not really sound like valve chatter like i could hear in my old 300? Does valves chatter all the time or just when your letting off of a hard rev?

 

[retro]

Ya, it probably needs a valve adjustment pretty bad. Used bikes need everything... it seems, cause folks don't know how to maintain them. Or they stop caring. Glad ya got it going, the solenoid will be easy to troubleshoot. Have fun!

 

[fishfiles]

The solenoid of a 300 is very expensive , but a 420 solenoid is cheap , the only difference is the color of the wires -------- don't waste you money on a Chinese solenoid , I have and had them last one start , 3 starts and one that started spinning on it's own and wouldn't stop till I disconnected the battery