The grenade finally went off!
I rode the bike wide open throttle for about 14 miles, some stops here and there.
The bike is doing 45mph at ~high 8k rpms on flat ground, going downhill it got up to 9300rpms. I was keeping up with traffic on a 50mph road.
The surprising thing was that the cylinder is totally perfect! other than the metal bits all over the engines guts, it just needs a new piston.
Does anyone know if there are higher quality pistons we can use for these?
It doesnt look like it melted through, just that there was so much pressure it cracked and blew through. Also to mention, just before this happened, my cdi cable broke at the base of it and i heard it "snapping" for about 10 feet before the engine stopped. Probably caused some MAJOR pre-detonation and exacerbated a weak spot that was already present (or so im thinking)
Im just happy I didnt even come near falling, and of course that i have a 3/4 helmet+leather jacket to ease the fall a bit if i did.
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From Norman***********
For some good info on why your engine let go Google "2 stroke hole in piston" you will have some good reading and info.
As for a better piston??? Wieco maybe, that might be misspelled. You will want to do a real good check of all the bearing on the crank for tiny flakes of melted aluminum, any in question should be replaced. Your Cdi malfunction probably is the leading cause of the failure and not a weak piston.
I rode the bike wide open throttle for about 14 miles, some stops here and there.
The bike is doing 45mph at ~high 8k rpms on flat ground, going downhill it got up to 9300rpms. I was keeping up with traffic on a 50mph road.
The surprising thing was that the cylinder is totally perfect! other than the metal bits all over the engines guts, it just needs a new piston.
Does anyone know if there are higher quality pistons we can use for these?
It doesnt look like it melted through, just that there was so much pressure it cracked and blew through. Also to mention, just before this happened, my cdi cable broke at the base of it and i heard it "snapping" for about 10 feet before the engine stopped. Probably caused some MAJOR pre-detonation and exacerbated a weak spot that was already present (or so im thinking)
Im just happy I didnt even come near falling, and of course that i have a 3/4 helmet+leather jacket to ease the fall a bit if i did.
============================================================
From Norman***********
For some good info on why your engine let go Google "2 stroke hole in piston" you will have some good reading and info.
As for a better piston??? Wieco maybe, that might be misspelled. You will want to do a real good check of all the bearing on the crank for tiny flakes of melted aluminum, any in question should be replaced. Your Cdi malfunction probably is the leading cause of the failure and not a weak piston.
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