Jump to content
Sign in to follow this  

Weak spark/intermittent spark- XR200

Recommended Posts

I have an XR200 that I recently rebuilt. It was drowned in a lake thelast time it was ran, so maybe the water created an undesireable resistance in something and shorted it out. Here is what it is doing: It is getting a spark, but a really weak one.

One you can't see in daylight. This weak spark also is intermittent, it won't crank over more than 8 times contiguously without stopping for a few cranks, then maybe the spark will come back. And of course, the bike will not start, and has not so much as sputtered, even after being pushed in gear for a distance. The timing is correct, and it has compression so I ruled those out.

Here's what I have done: Soldered ALL the connections, cleaned the connections, cleaned the grounds, and tested every electrical component except the CDI unit which I am told is not testable. The ignition coil, pulse generator, and stator coil, all check out and are within spec.

The connections are clean, and sometimes it does get a weak spark, and I have also tried a brand new spark plug. I am going to start replacing things, starting with the ignition coil because I can get one cheap. Is there a better way to go about this? I appreciate any and all advice I get in this matter. Thanks!!

Share this post


Link to post
Share on other sites

I had a similar problem. The best way is to find another XR200 and try swapping parts until you find what is broken.

I found a big long hill was best for getting it fired up the first time. I cleaned out the carb twice, new pilot and main jet, new plug, finally it ran.

Share this post


Link to post
Share on other sites

I have 3 different pulse generator assemblies that I have tried. That rules that out. So now it's up to the stator coil, the ingition coil, or the CDI unit, or maybe 2 or more? I don't have a large hill unfortunately, and my clutch cable has been giving me problems, plus me and my buddy both tried push starting it for a distance it never worked, not even with starter fluid. I wouldn't know where to begin finding another XR200 (I have very little $ to spend on this) I could switch parts out on.

I am looking at a 1979 XR185 coil, which looks like the exact same coil on my bike, I will try that. It came from a running bike, so if it still has a weak spark I will get another CDI unit an try that I guess.

Share this post


Link to post
Share on other sites

I just got a used CDI off of Ebay that supposedly came off of a "Running" XR200. Well, I get no spark with it. I have to kick it REALLY hard to see a small park, with all the doors shut. I put the old CDI back on and I kick it standard speed and I see a tiny spark. So I don't think it is the CDI. I guess it is the coil. I will get a coil off of ebay and see how that works.

Share this post


Link to post
Share on other sites

Xr200's are really suseptible to bad grounds. Make sure the ground is totally clean of rust or corrosion. ALso, make sure the cap isn't worn out. My cap slipped on and off and it wouldn't spark until I put a new cap on. Plus, since your bike went in the lake it probably shorted out the CDI, coil, and stator. Man, you have had the worst luck with this pile. What did you do to deserve all this bad luck?? :devil::awww::thumbsup:

Share this post


Link to post
Share on other sites

I cleaned and soldered all of the grounds. I screwed the plug directly into the cap, and the cap screws very securely into the wire. My next step is to replace the coil. If that doesn't work I have an XL coil I guess I could rig to work maybe. As far as what I did to deserve this, it's more of an accumulation of many deeds rather than one single deed.

Share this post


Link to post
Share on other sites

It was the stator coil! I put in one from an XL? and it started right up. I am going to go riding today. Also, the clutch was acting up big time, I couldn't even pull it in hard enough with all the slack adjusted to engage the transmission. It turned out it was lacking lubrication in a bad way. I funneled up a piece of paper and taped it to the opening of one end, and worked it until I saw oil coming out of the other side. Now it works perfectly. For some reason the XL coil cdi power wire was too short, so I had to splice in a wire to make it reatch, but other than that it works fine. Maybe now with the higher output charging system I can wire in a brighter light, too. Thank you all for all of your help!

Edit: The frankenbike looks like it has a small blue puff of smoke when I give it some throttle. Maybe after the parts all wear in?

Share this post


Link to post
Share on other sites

Thats good that you've fixed the problem. I just got my good bike back together after a long wait for parts :cry: . then found it wasnt the gaskets that were allowing oil to come out, but that the cam chain had worn right though the barrel!! I know how in the hell does that happen! But it was causeing oil to spurt out in one of the cooling fins between the barrel its self and the camchain slot. So I debated whether to pull the bike back to bits, but it was going so well apart from that. For the time being I've jammed news paper into the cooling fin/ hole (which you cant see). And it seems to have stopped the problem, so I may just leave it like that, however rugged it is.

John

Share this post


Link to post
Share on other sites

John, when it runs it has a "Chink chink chink" sound like a bag of wrenches, does it not? I bought 2 engines off of ebay and every one of them had a LOOSE timing chain which is responsible for the chain wearing through like yours did. I have some bad news. You can expect to have much of the material from the cylinder and crankcase to be work away. The metal that is shaved will clog up the oil rotor, and scar your oil pump, which will cause the camshaft to self destruct where the small bearing meets the bushing. The metal shavings will be everywhere. I suggest you have a look at your oil pump rotors to see what condition they are in.

As far as the timing chain goes, start the bike, and loosen the timing chain adjuster, which will be on the left hand side, on top of the crankcase. It will be a large 14mm plug with a 10mm bolt on top. You only have to loosen the large 14mm plug. While it is running, tighten the 14mm plug, and shut the engine off. This should take the slack our of the chain.

After an hour and a half of riding, it has a small oil drip, that is due to me not using any gasket sealer on the RH crankcase cover. It smokes a little, but I am HOPING it is because it is over full of oil. When it was running I took one of the cam adjustment covers off, and little splatters of oil came out, so I assume the oil pump si doing its job.

The engine ran really hot, but it was a warm day, I was in too high of a gear most of the time, and never really go up to speed on it except for a few times. The spark plug has the black ash on it, and a small amount of oil as well. It starts on the first kick, even when hot! I need a new clutch cable for it though, it locked up again, and shifting gears got pretty rough.

Overall I am pretty happy. I used the piston and cylinder from a seized engine, the rings had rusted to the cylinder. I sprayed wd-40 in it, and it unstuck immediatly, and with a small application of fine sandpaper it all came off. The piston and rings were in good condition. I used "The best" parts from eahc of the 3 engines, but it still needs crankshaft bearings, as they were wobbly, and a new lower end timing chain sprocket. I had a fun day, and will probably take it out tomorrow after I seal up the crankcase cover.

John, I also have 11 picture of what the inside of an engine with these problems looks like if you want them, but they are gory and shocking. (PM me your email address) Only an XR could sustain this amount of damage and still run fine.

Share this post


Link to post
Share on other sites

Yeah, I'd have to agree, only the XR's could indure that kind of punishment. Its kind of weird, cause I've done the "Automatic" camchain adjusting after putting it back together and it's not a real loud chain rattle but still is just there quietly (might just be me). The majority of the damage I think was done to the barrel pre to me owning the bike, and has only just recently worn through. Are the cam chain adjusters known to fail or actually work properly in these bikes? I say this because the 200 barrels I've seen have had the grinded look on the left side of the camchain slot like the camchain was loose? The oil doesn't seem too bad right now but I was planning on cleaning the filters and changing oil etc anyway.

Apart from what sounds quite serious really the bike starts first kick nearly every time idles well and doesnt burn all that much oil any more.

John

Share this post


Link to post
Share on other sites

The funny thing was that with all that damage, my bike started and ran great. When I first got it (I rode it once), I was checking out something behind the kick starter, I moved the kickstarter down past the compression stroke to get it out of the way, and it started right up. That amazed me bigtime. There is a brazing material called "Alumipro" that can braze aluminum and pot metals, I have had success with it, and you can get it on ebay. You could seal up the hole with it. As far as the chain tensioner, I do not know what their failure rate is.

Share this post


Link to post
Share on other sites

Yeah I changed the oil this morning and found a few bugs!! In the oil filter which surprised me a bit as i dont recall putting them in there. That Aluminium stuff sounds good I'll have to look into it. I also found what looked like a copper or brass shaving in the oil filter so I'm not sure any more.

John

Share this post


Link to post
Share on other sites

Yeah, the stators on older xrs seem to go bad, my friends and I have gone through a number of them. You can also use a stator from a 200x atc motor, but you need the cover and flywheel as wheel. The good thing about this is you can buy them on ebay for cheap and you can also get an aftermarkert one for about $70. I haven't seen an aftermarket one that fits a Xr200 yet.

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Reply with:

Sign in to follow this  

×