My flywheel puller came the other day so I popped off the flywheel on my Jackpiner and found this. [:0] Note the shinny brass color on the inside of the flywheel. I also have, what appears to be corrosion pushing through the red piece of the ignition along with all the other visible corrosion problems. The spark from the ignition is orange or yellow (no surprise), but the engine will fire with a push. Will this problem require a medivac to a specialist or can it be handled under an outpatient basis.
(http://www.pentonusa.org/forum_images/misc/flywheel.jpg) (http://www.pentonusa.org/forum_images/misc/)
Peter Petrick
'01 KTM EXC 520, '74 YZ 250, '86 Honda XR 250, '71 Hodaka 100, '74 SUZUKI TM 400, '73 Penton Jackpiner
Pete maybe it can be corrected at the specialist Penton Imports. Dane can re magnetize the flywheel and sometimes this does the job.
If you can swing it, Dane has this item called a PVL ignition.
At my intro race last month, Hal was announcing how there is a special technique ro starting a big bore Maico as the last group that took off had a Magnum rider struggle a bit to start. I reached out with my LEFT leg and casually kicked my Maico over just as I realized what Hal was saying over the PA. I wonder what that looked like to a spectator It sure was expensive, but if they made one for my truck , I would buy it. If it can make a Maico start easy, imagine what it can do for a Penton? James
Yamazuki-Kawahonda all sounds the same to me.. Real bikes were made in Europe
Pete,
What Doug & James say is the true fix, but I think for the time being you are working on a limited budget so here is my recomendations to keep you running while waiting for the Government to act on your situation. I would purchase some inexpensive brass wire brushes (cheap at Harbour Freight and other wholesale outfits) and clean up the metal areas on the red part (or the MotoPlat). If you take this off(the three screws) you have to mark it to besure to put it back on EXACTLY the way it came off so your timing won't change. Personally I would just leave the MotoPlat on the bike and do the delicate clean up the way it is.
Once you have the clean up done you can remove the spark plug and turn the engine over BY HAND and see it the flywheel clears the MotoPlat. IMPORTANT...ALWAYS GROUND THE SPARKPLUG WHILE TURNING OVER A ENGINE EQUIPPED WITH A MOTOPLAT. Just take the plug out and reattach the plug wire to the plug and lodge the metal end of the plug in the fins. This may sound like a lot of care for a MotoPlat, but I have run MotoPlats that looked a lot worse and they lasted for me.
Someone else may want to jump in here that has other ideas and that is fine I am just telling you what I would do if it was my bike.
Good luck Pete.:)
Ron Carbaugh
Peter,
The very first thing, and least expensive task to do, would be to remover the complete ignition system and mounting plate from the cases, and go a grounding refurb. Nearly all the Motoplat ignitions, depend on the mounting of the various components, to carry an operating ground. And we're not just talking about a few volts here. You are grounding a system that operates at 210 volts, so if you just use an Ohm meter to check continuity, you are not telling yourself if the grounds are sufficient.
The connections that must be clean and rust or corrosion free, are the stator to mounting plate, mounting plate to cases, cases to frame, and coil to frame. On all the KTM engines, the stator mounting plate is fastened to the seal plate, which is in turn, fastened to the cases. The magnesium cases are very poor for preventing corrosion, so the 6 screws that hold the plate to the cases, can form corrosion around the threads, and since the plate is sitting on a gasket, you loose the ground path.
My suggestion, is to remove all of the above mentioned pieces, carefully sand (or brush like Ron mentioned) the surfaces and reinstall everything. Unfortunately, this won't guarantee that the system will work, but at least you've eliminated the grounding as the problem.
If this process doesn't make things work, send it in to us, and we'll do the dynamic test on our bench, and see how things are working. Once the test is done, I'll get in touch with you, and let you know what I found. If the stator is faulty, I'm afraid that you will have to replace the entire system unless you want to go about locating another used system somewhere, as Motoplat has been gone for almost 12 years now.
The brass "shoe" by the way, is a counterbalance to the trigger pin shoe on the other side of the flywheel. Later versions of the flywheels, don't have the brass shoe.
Dane Leimbach
Penton Imports Co., Inc.
Thanks Guys! The operation is in progress. Upon reassembly, would a dab of Dielectric grease at the ignition mounting plate be advisible to enhance the grounding?
'01 KTM EXC 520, '74 YZ 250, '86 Honda XR 250, '71 Hodaka 100, '74 SUZUKI TM 400, '73 Penton Jackpiner
Peter,
Absent actual Dielectric grease, Motoplat said that you could use petroleum jelly, but yes, the formal product is a good idea.
Dane
Dane, how about running a dedicated ground wire from the Motoplat base plate up to the coil? I've done it to mine to, hopefully, eliminate the grounding problem. Soldered terminals at both ends.
Lew Mayer