> "Were a bit hacked off when the plugs started failing after a short time -our resident engineer reckoned that due to a design fault the ignition was firing twice in the 4 stroke cycle -and burning out the plugs -is this possible?"
Yes, I think most motorcycle ignitions use the "wasted spark" system. I think I'll call Joe Horvath at Revmaster and ask him about his ignition systems just to see if his ignitions use the wasted spark system as well . . . just out of curiosity. Revmasters don't use magnetos anymore, just dual electronic ignitions. I'm guessing the modern Rotax engines and perhaps the UL engines that Dan is considering for his Panther do something similar and why not? Magnetos are left-over tractor technology and it's amazing when you think about it that aircraft engines are still using magnetos . . . sometimes pressurized ones but still, 30-40 thousand dollar engines still using magnetos. That's a good suggestion that the wasted spark system is wearing out my airplane plugs, but Ive never noticed any abnormal wear with my motorcycle plugs over the years. I'm thinking the electrode wear I'm seeing with the Champion 10 mm secondary ignition plugs has something to do with the fact these are "racing" plugs. They are probably designed to wear faster in return for a hotter spark? I'll look into it. Need to get over to the hangar just now and pull some more plugs, check my valve adjustment and then head up to VGT Wednesday. Re the Tiny Tach - Thanks Mark for the remarks on your experience with them. This is my second one. The first one that came with the plane eventually died after many years. The batteries built in to them are not replaceable but they do last a very long time. This is the first anomaly I've ever experienced with the Tiny Tach. Yours is the first negative report I've ever heard in fact. They've been great 'till this probem just cropped up in response to my fiddling with the sensor wire. I'll keep fiddling with it and report back. ____________________________________________________________ 4 Veggies Not to Eat? NEVER eat these fruits and veggies (if you want a flat belly) http://thirdpartyoffers.juno.com/TGL3141/55638c879c0c6c872945st03vuc
