If Tim did the head, wouldn't he have done the machining to cure the sticky bucket issue? Was that a cure or just helped a bit?
Have you pulled the rest of the engine apart yet? When my wrist pin broke I found that the bushing in the rod was gone, one of those chicken or egg things but make sure everything is OK on the bottom end too, if something like that happened your assembled valve clearance could go away and cause the valve to hit?
Just a thought.
What on Earth?!
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who_gives_a6
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Entire engine was disassembled. I don't have much other than hand tools at the moment as I'm in the process of moving and most things were packed away before this happened. So can't do any precise measuring right now.
The crank rod looks OK to the eye but there is a "rough" spot when turning it on the crank. Guessing the bearing or something is jacked. Cylinder still looks good and usable with a hone. The bucket sticking could've just been a fluke or something. Maybe it was missed?
Amsoil assembly lube is made to break down in oil. I've used it in numerous cars and probably a dozen bike/quad engines. This has been the first failure, and ironically the lowest number of hours ran.
The crank rod looks OK to the eye but there is a "rough" spot when turning it on the crank. Guessing the bearing or something is jacked. Cylinder still looks good and usable with a hone. The bucket sticking could've just been a fluke or something. Maybe it was missed?
Amsoil assembly lube is made to break down in oil. I've used it in numerous cars and probably a dozen bike/quad engines. This has been the first failure, and ironically the lowest number of hours ran.
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who_gives_a6
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Crank rod is bent after further inspection and it's a stroker rod too.
Piston had a hole clean through the center but the most disappointing part is knowing a good piston was destroyed. Roughly 17hrs of hard riding and the piston/cylinder hardly looked used. Even the black coating on the skirts had no sign of wear.
Will be awhile on parts and don't wanna bother Tim right now so does anyone possibly have a worked/ported head or stroker crank/piston combo sitting around they may want to get rid of?
Piston had a hole clean through the center but the most disappointing part is knowing a good piston was destroyed. Roughly 17hrs of hard riding and the piston/cylinder hardly looked used. Even the black coating on the skirts had no sign of wear.
Will be awhile on parts and don't wanna bother Tim right now so does anyone possibly have a worked/ported head or stroker crank/piston combo sitting around they may want to get rid of?
Check for a crack between the main bearing and the counterbalance bore behind the stator. Use some scotch brite to shine it up so a crack can be seen.
. Massive stresses are involved in a valve drop thats a likely area to develop a crack.
Rods can be straightened if not bent to far. If you can eyeball the bend then its to far. Then Id order up a new rod.
. Massive stresses are involved in a valve drop thats a likely area to develop a crack.
Rods can be straightened if not bent to far. If you can eyeball the bend then its to far. Then Id order up a new rod.
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who_gives_a6
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Case looks good after checking but will be more thorough with that later. There was some metal pieces in the bearing area so gonna put new bearings in anyway just to be safe.
The rod has a bend barely noticeable to the eye at the top where it holds the wrist pin. Luckily the pumps and the rest were untouched and intake can also looks good.
The rod has a bend barely noticeable to the eye at the top where it holds the wrist pin. Luckily the pumps and the rest were untouched and intake can also looks good.