Author Topic: nearly no spark  (Read 3333 times)

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orderofsion

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nearly no spark
« on: July 21, 2004, 10:15:06 PM »
Can anyone out there help. My kx5 has been in the shed for 7 months , it was fine when it was put away but after since i got it out I have had the top end apart to fit a new piston , this was done with the engine out of the bike. Now I've got it back together I'm having electrical problems , when I first tried to start it it popped and fired a couple of times but would'nt start , I left it for a few minutes checked over the wiring connections (as the cdi was hanging loose out the side of the frame ) tried again and it started right away . After 30 seconds of running I reached down to earth out the cdi via the appropriate kill wire and as soon as my hand touch the wires/cdi the motor died without being earthed . No spark. It seemed that randomly moving the cdi and wires brought back the odd period of sparking , I thought I would see if I could ride it. No spark . A quick juggle around with the usual wires/cdi and it soon fired up , 200 yards later it died again .No spark and still no spark , no amount of fiddling seems to help . There is no spark at the plug , no spark at the plug lead , no spark out of the cdi but the main power feed to the cdi is producing a consistent spark but weak looking compared to the normal ht lead spark. So after all that preamble my question is this ; Does the weak but working output from the stator mean that my cdi is broken or could the problem still be in the stator ? There are very few motocrossers around here so I cant get hold of parts to try , any help or advice would be much appreciated.

Rick

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nearly no spark
« Reply #1 on: July 22, 2004, 05:37:05 AM »
I hate electrical problems.  So hard to test.

1. How are you testing "the main power feed to the cdi"?
2. It seems that since you had intermitent spark by moving the CDI wire around, the problem would be in the CDI.  

Rick

Offline Paul

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nearly no spark
« Reply #2 on: July 22, 2004, 05:52:26 AM »
Are ALL grounds clean and tight?

MIKECALDERA

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Can you say "Moisture" in your wires and Magneto?
« Reply #3 on: July 22, 2004, 03:34:49 PM »
Shame on you. 7 months without riding the beast? I can't go 1 month.

Somewhat easy fix.

You have condensation/rust :

1) Remove all wires and connectors
2) Look in the connector HOLES ahhhhhhh 99.9percent of problem.
Just like a car battery terminal they get corroded, always have clean contacts between metal.

If that doesn't work you must clean your Magneto with contact cleaner.

maybe even take it off and clean the cobb webs out of her heart.

Your CDI should be good UNLESS its cracked or fractured..then all bets are off.

Hope that helps
 :roll:
Mike

orderofsion

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nearly no spark
« Reply #4 on: July 23, 2004, 05:25:59 AM »
Thanks for the replies . I've been testing the power feed to the cdi by earthing it to the frame (no multimeter) and it produces a pathetic barely visable spark but still nothing comes out off the cdi or coil . Will the cdi only fire if it gets a good supply or should it produce some sort of output as long as some power is going in? I've just had the flywheel and stator off and had a good poke around the coils and wires - still nothing , I'm going to make a circuit tester to check for continuity along the wires. I've not ridden the bike for 7 months because I've been having a new frame made and since the bike was working fine when it went in I'm begining to wonder if some damage could have occured during the building or welding but of course I have actualy started it since I got it back , although only briefly .Any more advice would be welcomed , how to check a cdi or stator etc . Also incase I end needing parts has anyone got spare ignition parts. Thanks for your help.

MIKECALDERA

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nearly no spark
« Reply #5 on: July 23, 2004, 01:09:58 PM »
CDI baby. Bring her to an autorepair shop. Sounds like your getting the input from the rotor/magneto but No output. Stop right there. You may of damaged your CDI by dropping it or banging it or just plain moisture. Please tell me that you didn't weld with the cdi still on? I just welded a muffler bracket that cracked off but i stripped everything first.

It's cheaper than a Magneto but remember NO RETURN ON ELECTRICAL PARTS. Thats standard here in NY.

Go to ebay type in KX500 Ive seen about 3 of them in the last 3 months. I would buy new. Try Denniskirk.com or motosportoutlet.com but don't go to the dealer.

That should do it. If you really care go to sears and buy a real electrical tester for 20 bucks min.
m

MIKECALDERA

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nearly no spark
« Reply #6 on: July 23, 2004, 01:19:10 PM »
CDI baby. Bring her to an autorepair shop. Sounds like your getting the input from the rotor/magneto but No output. Stop right there. You may of damaged your CDI by dropping it or banging it or just plain moisture. Please tell me that you didn't weld with the cdi still on? I just welded a muffler bracket that cracked off but i stripped everything first.

It's cheaper than a Magneto but remember NO RETURN ON ELECTRICAL PARTS. Thats standard here in NY.

Go to ebay type in KX500 Ive seen about 3 of them in the last 3 months. I would buy new. Try Denniskirk.com or motosportoutlet.com but don't go to the dealer.

That should do it. If you really care go to sears and buy a real electrical tester for 20 bucks min.
m

MIKECALDERA

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nearly no spark
« Reply #7 on: July 24, 2004, 12:47:44 PM »
http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&tc=photo&rd=1&item=2485410553&category=35594#ebayphotohosting

here's a coil system that should work...go get it fast and cheap.

good luck. I hope thats your bid since its the only one

Mike

MIKECALDERA

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orderofsion

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nearly no spark
« Reply #9 on: August 03, 2004, 01:49:19 AM »
Thanks to everyone who took the time to reply with their advice . The machine is fixed ! I made a small circuit tester and tested all the wires between the stator and the cdi output , everything seemed to work , infact it didnt matter which wire I put the tester to I always got continuity through to the cdi output even if I put the input to the engine cases or the frame rails. I thought that this couldnt be right then I realised that the power (from the tester) was running down the wires I was trying to test into the stator then back up all the other wires and into and out of the cdi ! So I disconnected all the wires from the cdi and tested them with the stator off the bike , sure enough the red and black main power feed out of the stator had an invisible break , you couldnt see it but power wouldnt go through .Problem found , problem fixed total cost ?5 for flywheel removal.  Thanks everyone.

Offline Paul

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nearly no spark
« Reply #10 on: August 03, 2004, 03:29:43 AM »
Glad to hear it wasn't anything too terrible to repair  :drunk: