No heat cycles, no break in proceedure, no leak test prior to startup, incorrect jetting, inadequate warm up, incorrect oil/fuel ratio, no plug chops, poor build, the list is endless.
best piston to buy
- Thread starter mud runner
- Start date
http://www.blasterforum.com/full-rebuilds-128/mud-runners-rebuild-50370/ ill post a pic of what did it in a few mins
I a 04 blaster and i ride pretty hard first rebuild was this year stock piston lasted me 8 years which i think is pretty good. it blew up this year and i now run a namarua piston rides great my builder says they last longer than wiesco what ever he says im gonna go with
OEM,Namura,and WSM make great cast pistons! If your engine is set up properly with the correct piston to cylinder clearance,JETTED CORRECTLY,uses a quality oil at the right ratio,and is WARMED UP BEFORE USE,a cast piston works PERFECTLY even in MODIFIED ENGINES (ported,re-chambered head,etc)! What cracks me up,are the people that have a worn bore,but are cheap,or lazy,so they just slap a new cast piston or wiseco in to "cure" they're problems. I've seen wiseco's crack,and I've seen wiseco's smear the bore from no warm up. Proper set up and inspection is the key. Look how long those stock pistons last with abuse.YEARS not hours.
Cast pistons are how I get so many cases to repair. 
You cannot account for all scenarios that could cause the demise of a top end (laziness and cheap aren't the only ones). I've seen water and trash in gas, I've seen blocked fuel tank ventline, I've seen accidental emursion in water... Any one of those can cause a failure and none have anything to do with cheap or lazy.
Joe, this is one area where we will have to agree to disagree. You are correct that a cast piston, if everything else is right, will run and run well for a long time. My entire argument against cast pistons is their end of life scenario. Forged pistons will stay in one piece and lock to the sleeve tighter than a drum (tight enough the top end has to be removed with the help of a 2"x2" and a hammer sometimes). Cast pistons will crumble into 1 million little tiny aluminum balls which get in everything ruining big end bearings, crank bearings, and even sleeves sometimes.
If everything works perfectly you should never shatter (or crumble in the case of a cast piston) a piston OR smear it down the sleeve but if I have my choice..... HA! smear away!
You cannot account for all scenarios that could cause the demise of a top end (laziness and cheap aren't the only ones). I've seen water and trash in gas, I've seen blocked fuel tank ventline, I've seen accidental emursion in water... Any one of those can cause a failure and none have anything to do with cheap or lazy.
Joe, this is one area where we will have to agree to disagree. You are correct that a cast piston, if everything else is right, will run and run well for a long time. My entire argument against cast pistons is their end of life scenario. Forged pistons will stay in one piece and lock to the sleeve tighter than a drum (tight enough the top end has to be removed with the help of a 2"x2" and a hammer sometimes). Cast pistons will crumble into 1 million little tiny aluminum balls which get in everything ruining big end bearings, crank bearings, and even sleeves sometimes.
If everything works perfectly you should never shatter (or crumble in the case of a cast piston) a piston OR smear it down the sleeve but if I have my choice..... HA! smear away!
