1987 WR250 SEM ignition problems.

Had a few minutes to snap some photos for ya. First is the 250WR in roughly firing position. I didn't put a dial indicator on it, I just rolled it over till it felt like TDC. It's close enough to give you the idea. There is no timing pin hole in the flywheel because it's timed via the "hole with pointer" method. Hole with pointer at roughly 5 o'clock, open hole at roughly 11 o'clock, when near firing position.



Second is what you see through the hole with pointer... the degree field. Again, don't go by the exact alignment, but when correct the pointer is on this field.



Third, is the exact same model of stator on the bench so you can see what it looks like. Notice this one says "83 250WR open R-Bl". It was the original, and developed open circuit Red-Black and stopped sparking. This is probably the most common SEM failure: Open circuit on Red-Black.



Fourth, is just a comparison so we can all keep our eyes open as we shop for used stuff.
Left is the 83 250WR, clockwise rotation, has degree field, is timed with hole/pointer.
Right is 1994 KTM 300 EXC, counter-clockwise rotation, no degree field, is timed with pin through flywheel.

There are all combinations of these features. Notice that you can't tell which rotation it was designed for by looking at it. I'm still working on finding out if there is actually any difference in the stator itself for the different directions of rotation. Nobody seems to know... but I have tested some that test in a way that indicates that they have a diode inside, and probably will charge in one direction but not the other. But that's for another post...


Both of these stators are dead, by the way.
Both are open circuit on Red-Black.
Both left me stranded in the MOFN.
Both times I was able to find suitable replacements through the good people of good forums like CAFEHUSKY !

Hope this helps.

Hi Ron,

That would be great, please PM me when it suits you, I shall PM you my details, let me know shipping etc, happy to make a donation to Cafe Husky or Pay it forward in some way if I can.

Thanks so very much.

The info I have gotten here is the best, after reading all and looking at the photo's etc, I had the assembly in the correct order, wiring all correct etc, but it was the fact I had a KTM counter clockwise Stator that was stopping me, they fire at a different point, I have spoken to a guy who rewinds them and was told that they wont work, they are wound in a different sequence, they would need to be rewound for clockwise rotation.

I played with mine over the weekend and got it to fire with the ols stator and the CCFL invertor powered coil, but not reliable enough to run, just wanted to prove the assembly was correct, and the photos above show it was, I thought I was going crazy, or crazier (is that a word?)

Thanks again to all who have taken the time to help, I am not a great husky expert, but know my way around a milling machine, lathe, tig etc, if I can help anyone, please feel free to ask.

I have fitted a Chinese cdi [ honda postie copy ] and coil to my 86/ WR using the SEM stator and it works great.
Not original but who cares .
Am now fitting a complete Chinese [ honda postie copy ] ignition to my 85.

MORE INFO PLEASE.

Was it a kit, or off ebay ?, did you have to mod the flywheel or crank?

Please dont tease, more info please.

IT IS ALIVE, second kick, just like old days.

I have been in email with duccman, who has been a huge help, with so much information, different idea's and things to try.

I bought a CDI and coil set of ebay, this one, http://www.ebay.com.au/itm/250908061794?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1439.l2649

It is a DC cdi, powered at the moment by a battery, I got this one as I did not want the extra drama of setting up a battery less system before i had it running, I will fit the REC / REG i have, along with a capacitor and see how I go, but for now, it 12 12v DC powered by small bike battery,, total loss at the moment.

I used the wiring diagram shown here, http://mastercircuits.blogspot.com/2010/08/dc-cdi.html

I had to use the china Coil as well, the SEM unit would charge but not fire, so I fitted up the china coil and HUGE HUGE HUGE blue sparks at very slow kick speed.

Spank plug installed, turn on fuel, turn on choke, remember the bike has not run for 10 months, second kick, it fired and idled down nice, choke off, runs up nice, clean, did not go too far as only on work stnd for now, I need to mount the battery, wire in the REC/REG to charge it.

I walked back out 30 mins later, turned on "key" (toggle switch for now), half hearted kicked, away it went, first kick, smooth perfect idle.

I will post up a full wiring diagram of how I hooked it all up over the weekend.

This is running the SEM stator with the non functioning coil charge (excite) winding, but the trigger and gen coils are fine.

the CDI coil was $25 shipped, I had the battery, and all the other stuff, so if not having it 100% original is not too important, then this will work, I will be fitting up a PVL unit soon, but it is so nice to know this works and can get an old girl running, if you have a bike with a dead stator, check the resistance, if the trigger winding is fine, for under $50. you could be up and running, not perfect I know, but it works so easy.

I have to say a HUGE thanks to duccman, he has been such a great help, I would never have tried to set up a china CDI with my stator, talking to Mike has got me thinking outside the box.

THANKS MIKE, I owe you big time, we are going riding on sunday, the Husky is going out for a run, first one in 10 months,

HAPPY HAPPY HAPPY man.

Hi all,

Went for a ride this morning, got all the wiring in and harnessed up, still need an ignition switch, but until I try setting up the Rec/Rec and a Cap as a battery eliminator, the current set-up will do.

I have a 2 pin plug up on the bars which drops out the battery pos and neg, the draw on battery is 5.5 m Amps, so it should last a little while,

It started first kick again this morning, I started and stopped it 20 times, first kick, just like it used to.

Attached is a rough wiring diagram of how I wired it in.

I have used Duetsch plugs everywhere so far, once I have tried or set up the BEC, i will harness it up.

I am sure that half the starting issues with these bikes is crap spark, this bike was a good starter, but my old one (wr240) was a pain, until I had the stator rewound, then perfect.

Still more to do, but I can at least ride it and play, I can also get my 240 going too maybe.

Have a few dud SEM stators lying around and saw somewhere that Steve at http://www.uk-motoplat.com/home.html can fix them.
So I sent him one to see what happens.
Steve is helpful , knows what he is doing , cheaper with his quotes than others I had received and the turn around time was not too bad either.
I would recommend giving him a try with SEM and Motoplat ignitions.

I wrote this before I had fitted the stator .
I have now changed my mind. This guy only says he knows what he is doing , it all sounds great until you have paid.
This guy does not do good work. The stator I paid $300 + $30 postage to get fixed has no spark at low flywheel speeds.
Real handy on a 400.
I have another stator I borrowed and it works fine so there is no other problem with the earths or the SEM coil setup.
He has offered to have another look at the stator but I live on the opposite side of the world and if he couldn,t get it right the first time then who's to say he will get it right the second or third time.
Pissed off.

Mike I hope you can offer some advice, I have no spark after refitting the SEM stator and coil, based on the pics below, how would you wire this chinese coil to my SEM stator?

Here's one of them
http://www.cafehusky.com/threads/pvl-ignition-advice-500-lc.30878/page-3
Half way down the page Pez has some colour photo's.

http://www.cafehusky.com/threads/another-sem-question.80318/page-2#post-533761

Thanks Mike, I was just tinkering in the garage and connected the red from stator to red/white on cdi, green from stator to white on cdi, black from stator to green on cdi (I'm assuming that the green could run through the kill switch?) and I now have spark! I haven't tried to start it yet, I'll set the ignition timing first at around 1.8mm to limit kick backs. Does this sound about right?
Tony.

I can't remember what I did Tony but mine is nowhere near as advanced as the manual says.
Wasn't looking for hp just reliability.
1.8 should do it.

I guess as long as it runs well, it will do, can these be wired in a way that will harm the stator? The earth is the black from the stator, as is the green on the cdi, that's why I thought the kill switch could be used on that circuit, or do I have that arse about?
Tony.

should be fine staying less than 2mm btdc..i run 1.6 on the 430 currently with no kickback..

I started with just a bare cdi so I have no colours just positions.

No worries Mike, your posts have been an enormous help, I wouldn't have thought it possible otherwise! Thank you!
Tony.

I have sent a request to rickystator about doing repairs on SEM and have not gotten any response as of yet. Pretty soon I will play with one of the duds to see if I can rewind the bad coil(s)

I have seen one with the poo off and it looks like the earth connection corrodes.