is my piston shot?
- Thread starter 2smkfullstroke
- Start date
Piston is done. May have gotten some unwanted debris in the cylinder. Leaky exhaust flange or dirty air filter.
Damn. I was afraid of this. It's a Spair motor that when I ran it had no problems at all with it. Would you think running this would be fine for a little while or new piston is in order. I'm in the process of building another bike for a winter project and really like this motor the power band in it is just freaking amazing. But I'd rather put money into other upgrades.
Do you always warm the engine up well before you ride.
A pic of the top of the piston may help to determine if the jetting is off.
A pic of the top of the piston may help to determine if the jetting is off.
I'll have a pic soon just got off work. I always let it warm though least 10 min while I get my gear on. When I tore it down there seemed to be a lot of oil on the crank iv never seen befor? I run amsoil interceptor 50:1
That crosshatching looks wicked, at 50:1 (which is just not enough oil for a 200cc engine, no matter what the manufacturer claims) I doubt it would have retained up enough oil to properly lubricate.
Crosshatching should be close to 45 degrees to allow migration of oil up and down the bore.
Horizontal hatching allows the rings to wipe out oil.
Crosshatching should be close to 45 degrees to allow migration of oil up and down the bore.
Horizontal hatching allows the rings to wipe out oil.
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So try 40:1? And what do you mean about the cross hatching exactly retaining to my situation. And it just seems like a lot of oil on the crank for not enough at 50:1
32:1 is the recommended ratio for a Blaster.
The crosshatching is poor and may be the reason that the piston is scuffed.
It has not held enough oil to lubricate the piston adequately.
A shiny bore will not hold enough oil to provide a buffer between piston and cylinder.
There should be a lot of oil on the crank and moving parts, that is how 2 strokes are lubricated, the oil gets thrown around.
In Amsoils small print they state that many racers modify the oil ratio from 50:1 to suit their setup, which advises me to use more oil in my mix to suit the engine size.
The crosshatching is poor and may be the reason that the piston is scuffed.
It has not held enough oil to lubricate the piston adequately.
A shiny bore will not hold enough oil to provide a buffer between piston and cylinder.
There should be a lot of oil on the crank and moving parts, that is how 2 strokes are lubricated, the oil gets thrown around.
In Amsoils small print they state that many racers modify the oil ratio from 50:1 to suit their setup, which advises me to use more oil in my mix to suit the engine size.
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I had seen in other posts run what the bottle says that it says something specific for a reason. Each formula has its own ratio. I'll try the 32:1 I'll most likely need to rejet i assume?
we need to know the mods you have done, air temperature, elevation where you live, and what is in there now?
You most certainly will have to re jet as adding oil will lean out the fuel content.
It would be a great idea to have the cylinder honed properly if it is within specs.
It would be a great idea to have the cylinder honed properly if it is within specs.
Fmf fatty power core 2 full exhaust. Bored 80 over wiseco crank and piston. Aggressive port n polish. 2 stage Vito reeds stock carb 320 main stock pilot needle 2nd clip. cut the whole top of air box lid off and placed a k n n car filter for protection.
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