89 Honda fourtrax 300 runs bad

[Kris Walters]

So I bought this 1989 fourtrax 300 2x4 as a non running quad(no spark).finally got the thing to spark yesterday accidentally,by pushing the starter button while the kill switch was off.(I was holding the coil wire and it shocked me).so low and behold the kill switch for some reason works backwards.anyway it started up but runs terrible.it will sit and idle for as long as you let it,but as soon as the throttle is touched it boggs,and dies.thought it was a fuel issue,so I verified clean fuel source and flow from the tank.also cleaned the needle valve and jets in the carb,but that didn't help at all.if you very carefully apply throttle it will run and move but if you get past 25-30% throttle it will start popping out of the exhaust and loosing power.

Edited August 5, 2018 by Kris Walters
Added info

[davefrombc]

Clean  the carb again. You  have a classic "running lean" problem  when you open the throttle . It  could be a plugged passage  or the  tiny drilled  holes in the  main  jet  tube,  the  idle  air screw maladjusted or possibly the float level set too  low so the float bowl  doesn't  fill  properly.  There  is a download  of the service manual  that would cover  your  machine  in the forum's download  section .

 

[Kris Walters]

The float is plastic,so I'm not sure how to adjust it.the main and pilot jets are good and clean.also the plug was black and sooty in appearance.the pick of the plug looks gray but it's actually black

[Kris Walters]

[Kris Walters]

Tore into the carb again and it is spotless,it seems like a rev limiter is causing it to act this way or weak spark.plus the whole thing with the kill switch only working backwards("run" kills it and "stop" gives spark) I posted a video of it running and me trying to rev it,but the sound quality sucks.

Clean  the carb again. You  have a classic "running lean" problem  when you open the throttle . It  could be a plugged passage  or the  tiny drilled  holes in the  main  jet  tube,  the  idle  air screw maladjusted or possibly the float level set too  low so the float bowl  doesn't  fill  properly.  There  is a download  of the service manual  that would cover  your  machine  in the forum's download  section .
 

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[davefrombc]

It  is possible a weak spark  or faulty  plug that fails under increased pressure could cause the problem.  I still  think  it  is  a lean  burn  problem  though. It  could be  from a plugged  passage or a tiny  hole  that you're  missing  in the  jetting ..Check   for a  leak  or  crack  allowing  air to  enter  on the  block  side of the  carb too.   There is no rev limiter  on your  quad..  My own  quad is  a 1991   Honda Fourtrax 300 FW  ..  basically the same  machine you have except it is  full time  4 wheel  drive.

Here  is a  video  on servicing the carb.

 

[Kris Walters]

The carb has been removed and cleaned by a professional.It is confirmed clean and all the passages are clean as with the jets.i still feel it's electrical/ignition that's causing the problem.One thing I have noticed is that the reverse light stays on even though the bike is not in reverse.

[davefrombc]

If that's the  case there  could be electrical  problems  causing  it.  Get a  spark  checker like this one  and it'll tell  you right away  if the spark  cuts  out when  you try to  accelerate .

https://www.amazon.com/JND-Fool-proof-Engine-Ignition-Tester/dp/B0042KJV9U/ref=pd_lpo_vtph_263_lp_t_1?_encoding=UTF8&psc=1&refRID=XPM0TCGERPD45V7VN6DG

[Kris Walters]

Thanks bud.i think if I put the inductive lead from my timing light on it it will show the same thing.it should stop strobing when it looses spark

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[davefrombc]

45 minutes ago, Kris Walters said:

Thanks bud.i think if I put the inductive lead from my timing light on it it will show the same thing.it should stop strobing when it looses spark

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That should work  as a spark test too..... and with  a brighter ,easier to see  light. When  you finally find the fault,  please let  everyone  know  just what it was .  Every time someone posts a  problem  solved  it helps the  next  one  with similar  trouble .

 

[Kris Walters]

Will do.i think it's gonna come down to the alarm box.being the "reverse" light stays on regardless of which gear it's in.

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[Kris Walters]

Picking up the new alarm box today.believe it or not the ebay seller gave a complete refund including the expedited shipping costs on the boxes that I already purchased.