which piston should i run?

justin03blaster

New Member
Jul 11, 2009
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huntington beach
so my 03 blaster blew the top end this is the 1st time since ive had it so which pistion do you guys run/perfer i would like to get more power out of it but i cant afford a big bore kit it has a fmf full exhaust and im planning on doing the oil injection block off and im also thinking about porting it any thing else i can do to get more power thanks.
 
Wiesco forged piston. Porting, v-force 3 reeds, k and n filter or uni filter and take air box cover off, new carb. 28 or 30 without porting and 30 to 34 with porting depending on how aggressive the port job.
 
and if you go the stoker route do that before the porting. Then have them port it to match the stroker crank.

Another great mod is to get you head redesigned and cut. This should cost 60ish dollars.
 
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It really depends on what kind of rider you are.
OE pistons are cast because they are light, run tight clearance specs, and breaking them in is fool proof. Because they are softer if you change them before the fail, very little cylinder wear is common and a replacement piston of the same size can often be re-used.
Warm up for cast pistons is quick and simple usually a minute or two and ride off easy for the next minute
However they are more brittle and dont stand up to detonation or pre-ignition as well and if left until they fail its usually pretty bad.

Forged pistons like Wiseco are much more durable and withstand punishment better, however they usually dont produce as much power as they require more clearance and often heavier.
Break in for Forge pistons is much harder then cast and they are far more prone to cold seizure and poor breakin results. The Pistons require a LOT longer warm up, usually 3-4 minutes of idling while lightly blipping the throttle every 20 seconds or so to keep it from loading up. Once the cylinder head is hot the bike is ready to ride off. Its should also be driven slowly for the first minute or two to let the piston slowly come up to temp. The other downside to forged poistons, when they are worn out usually the cylinder is as well and needs a fresh bore....

IMO use a wiseco piston, Amsoil Interceptor or Dominator at 50:1 and allow your engine to warm up 4-5 minutes each time before you ride off .

For people running the injection system I recommend using Amsoil in the injector tank but because it does not have direct port/bearing injection, also mix your fuel at 100:1 using Amsoil interceptor.
 
so my 03 blaster blew the top end this is the 1st time since ive had it so which pistion do you guys run/perfer i would like to get more power out of it but i cant afford a big bore kit it has a fmf full exhaust and im planning on doing the oil injection block off and im also thinking about porting it any thing else i can do to get more power thanks.

if you are going to do any of the things that you mention above, let your engine builder recommend the parts he/she will use in your build. Taking advice from peps here will most likely come into conflict with what your builder recommends.

I can tell you from experience, that when someone comes to me for a build (bore/port/stroke) and they start telling me the things they want used in the build because thats what they "read on the internet", I would often tell them to go buy the products first, then bring me the lot of parts and engine. I would assemble what ever they supply and offer ZERO warranty.

A good long-term builder will have had experience using a variety of parts over a period of time. Parts from suppliers that will stand behind those parts and so will they.

If you are thinking of having someone port your motor at the same time your needing a bore/piston, this is the time to do it.

What works for some here, may or may not work for you and if you put the horse before the cart, you may find yourself redoing or replacing parts prematurely.

Talk to a builder first, so what they recommend.