Reliability of CDI, coil, and plug wire...

motochick

Member
Mar 10, 2001
122
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I went riding this weekend with some friends in some really fun single track and one of the guys had a problem with his 2000 Husaberg. NO SPARK! Now, I know this is a problem with these bikes and it is not a KDX, but it got me thinking. (watch out!) My bikes are pretty old and they still have the stock ignition parts in them.

Do I need to worry about the ignition parts (CDI, plug wire, coil) failing and leaving me stranded in the middle of the forest? When they break, do they give any warning? Should I replace any part of the ignition system because of age? I mean, even the plug wires are 11 years old.

I really pride myself on having the most reliable bikes possible. I change things before they wear out and service my bikes weekly. The ignition system is something I know nothing about because I have never had a failure or even heard of a failure as catastrophic as my friends Husaberg. (after we towed him out of the singletrack, he left his bike and came back for it later that nite in a 4X4.)

I don't want this to ever happen to me! Any advice? I did read the whole thread on ignition timing, but I am more concerned about parts failure. Thanks in advanced,

Brenda
 

MADisher

Grand Data Poohbah
LIFETIME SPONSOR
Apr 30, 2000
377
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Well,

The quickest way to make sure you never need something is to carry a spare. CDI's aren't cheap, and I'm not aware of any reliability problems with KDX ignition parts. But if it's an older bike that you have and you know you will keep it. I'd be on the lookout for spares. There are bikes being parted out on e-b-a-y all the time. If you can pick up both a CDI and stator cheap you'd be set.

There is nothing worse than having to pay top dollar for a rewind or rebuilt stator, or a CDI if you can find one because yours is dead and you wanna ride this weekend.

I have some of these spare parts for my RM. er well I have the older 'weak' stator and a known good CDI. Nothing yet for my KDX.

-MD
 

motochick

Member
Mar 10, 2001
122
0
Actually, both stators were rebuilt because I wanted more power output for a bigger headlight. I am not too worried about that. I guess I am not? Like I said, I know nothing about these ignition systems. Anyone care to educate me? I don't mind carrying a spare if I thought it would be something that could spontaneously die. What is nice is that I have two identical bikes and I steal parts off them all the time to get one ready for the next ride. I also have many spare parts for both including a brand new unused cylinder!

Anyone else?

Brenda
 

JohninKY

Member
Nov 18, 2000
131
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The ignition on my 1989 KDX went bad this year. It didn't just quit. It started running rough and wouldn't run clean on top. It gradually got worse.

I wouldn't worry about the ignition leaving you stranded.
 
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CrashDoc

Member
Mar 6, 2001
26
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Hello MotoChick/Brenda,
So you've been out 2-wheel hiking and observed the reality of relying on electrical controlled mechanical devices. Yes it was kinda a bummer when the Hussie coasted to a stop, BUT you know as well (OR better then most individuals :-) that no matter the manufacturer or the age anything electrical/electronic can fail at any given time. Kinda makes ya wonder how those Tech 8's would do for long distance hiking ;-) , thinking that a loss of electricity could shut down a otherwise fun day of single track/exploration.

I helped do some preliminary troubleshooting on the Hussie the other nite. Started with the kill/On/Off switch; good , coil; good , then did the stator ohm readings and it appears like one leg of the stator output has went south/open. We didn't have any tech knowledge on how to check out the CDI so hopefully the problem is just a bad stator, kind a bummer on that new of a bike.

I can certainly appreciate the thought of carrying spare stuff, the problem being that every manufacturer seems to have a different electrical arrangement that is specifically molded/configured to a particular setup so you lose universality of useage between different bikes. We had 5 different manufacturers represented on that ride and we were the only two of the same manufacturer origin. I even wonder between our different aged KDX's if there would be any interchangeability??

Well I hope that some more of the experienced KDX owners will share their electical experiences so we can learn what might be good to pack along, besides a Buddy Tow.......... that doesn't seem to work too well on the steep loose uphills!! I LOVE my new Tech 8's, they are so comfy and walk-able, however I don't think they would be the ticket for hiking in!! :-) I'll call you later and chat! CrashDoc/My
 

G. Gearloose

Pigment of ur imagination
Jul 24, 2000
709
0
Brenda,

If you wanted to peg the coolness meter:

If you could find room under the tank to mount a redundant coil, plug wire, and CDI, and wire a waterproof and high quality DPDT switch to both from the stator, you could switch to a secondary ignition almost like an airplane after switching plug boots.(mag1/mag2) without tools or disassembly, then the only singular unit left is the mag coil on the stator plate. You could use a ‘dummy plug’ to keep the unused boot clean, dry and ready.

If you had your stator rewound, they may have only done the lighting coil unless you specified to do the mag too, they are discrete units on the stator plate.

Its just a theory, but it may get some ‘get it home’ robustness you desire, and we will be in awe.
 

dirt bike dave

Sponsoring Member
May 3, 2000
5,349
3
The majority of electrical problems I hear about are bad stators, and had one go bad on my '84 KDX. Luckily, it did not strand me on the trail.

It seems that electrical problems can often be temperature or moisture related. If you have a weak system that is sensitive to cold and wet, you might not be able to get the bike started in the morning, but at least you don't get stranded on the trail.

If the problem rears its ugly head when hot, you can sometimes let the bike cool down and limp it home.

Probably not worth carrying spares with you.
 

motochick

Member
Mar 10, 2001
122
0
John, what exactly went bad on your bike?

Gearloose, don't tempt me! I am just crazy enough to do somehting like that!:D

It sounds like maybe this is something I shouldn't worry too much about. I just thought that because my bikes are way old, it might be time for this stuff to fail. Any more thoughts on this? Sage? Dave? Dan?

Brenda
 

MADisher

Grand Data Poohbah
LIFETIME SPONSOR
Apr 30, 2000
377
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Well,

I didn't necessarily mean carry the stuff with you :eek:

Just the fact that you have it, in the truck, on the trailor, in your toolbox, is enough to keep the originals from failing. Besides if you can find a stator or CDI cheap (someone parting out a bike) they are great to have in the event you need one. You don't then have to wait for one you can afford. It/When the one you have fails.

-MD
 

Canadian Dave

Super Power AssClown
Apr 28, 1999
1,202
0
Hi Brenda,

You'd normally expect to see signs that something is going bad, the engine will start to miss fire at higher rpms, the power going really flat, things like that. You will normally be able to limp home. The stator coil seems to be the first to show its age. Is it worth rewinding just in case ? ? ? it's a crap shoot. Yours might last 25 years or go bad next week. If you are concerned you might consider grabbing the multi meter and testing your system to make sure all looks well. You might want to pull the plug and watch for a good quality spark and monitor it over time?

Carry extras? Well if you ended up with a good used CDI and ignition coil in your collection then stow it away in your tool box just in case. Problem is often times it's a stator coil, which would be a little more difficult to change out on the trail, you'd end up with a big fanny pack.

A note of caution, its not at all uncommon for a CDI to test outside the ranges quoted in the shop manual and still function perfectly so don't be concerned if it's a little off. I've tested brand new CDIs that didn't match the spec. You'll want to watch for a dead short etc where there shouldn't be one rather than one circuit thats a little off kilter. Fact is if your CDI was bad it would have let you know already so I'd focus on testing the coils from time to time.

You know now that you've brought up the topic . . . . . . well maybe you'd better knock on wood ;)

David
 

canyncarvr

~SPONSOR~
Oct 14, 1999
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Don't know if this was missed or not...could make that case just reading the words and not putting understanding between the lines??

Brenda, you said,
both stators were rebuilt because I wanted more power output for a bigger headlight
.

The term 'both' applies to two bikes? Or two stators on one bike? The latter doesn't make sense because of the 'headlight' reference.

As Gearloose said,
they are discrete units on the stator plate.
talking about light and spark coils.

Yeah..take a big fanny pack to carry the tools to change your exciter coil..impact wrench (hopefully not a pneumatic one!)...etc.

IF you do get one (exciter coil) for a spare keep in mind that unless you do some advance prep, the parts won't swap without some soldering. Maybe your tool bag is big enough for one of those, too!

Part of the fun is not knowing if you're going to make it! Going to death valley years ago in a doorless (hoodless, too) english ford with a beer keg in the trunk for a gas tank was MUCH more fun than the same trip would be in my wife's new tundra! Wouldn't have spent so much time on the side of the road looking for a cracked distributor cap aggravated by wet nights on the beach at morro bay, but the enfo was a big part of the fun!!!
 
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motochick

Member
Mar 10, 2001
122
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Canyncarvr, I meant both bikes were rewound. I like to keep both bikes identical (except of course the cylinders) so that I can hop on either one and they feel the same. If I do something to one, I do it to both.

So I guess I am OK with my 12 and 9 year old CDI, coil, and plug wire. Those are the parts I was most concerned about. Not so much the stator, but then I didn't realize that it too could be vulnerable.

Has anyone tried one of those "high output" aftermarket plug wires? Are they a gimmick? I would tend to think that OEM would be the safe way to go, but I just don't know enough about this subject to say for sure either way.

Thanks for all the help and advice. I will just keep my buddy tow in my pack and as usual as many spares as I have in the truck.

Brenda
 

dirt bike dave

Sponsoring Member
May 3, 2000
5,349
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Cnyncarvr raises a good point about the two different sides of the stator. When I had mine rewound, they did both sides. I guess I assumed that anytime you sent your stator off for a rebuild they would just automatically rewind both sides. Now I'm wondering if my assumption is correct - do they routinely rewind both coils or just one?
 

JohninKY

Member
Nov 18, 2000
131
0
Originally posted by motochick
John, what exactly went bad on your bike?
Brenda

I replaced the CDI and the ignition coil. I'm not sure which went bad. It wasn't running well on top and I had the spares so I changed them out and the problem went away.

I wouldn't worry about the ignition. As far as carrying spare ignition parts, that's ludicrous. You'd be better off towing a complete parts bike. If you want to worry think about all those trees, roots, mud and rocks lurking out there to make you a DNF. Enjoy riding, don't sweat the little stuff.:)
 
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motochick

Member
Mar 10, 2001
122
0
Thanks for all the responses. Ii won't sweat the little stuff, but just to make it clear, I didn't want to CARRY extra parts with me, I was curious if I should REPLACE them. I guess I won't untill they go bad.

Thanks again everyone,

Brenda
 
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