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the webcams are pretty good priced i believe, thats what i was going for before I came across mine on ebay. No you dont need a new piston when you get a cam but if you dont already have a high compression piston I would reccomend getting one at the same time or before the cam.
 
i got my hotcam at a good price. dont have a core charge either. its just a brand new cam. not sure if you have to send in your cam for webcams or not, but i know you do on some.
 
I don't know if this piston will work but I got a JE piston from powoll from thier 365cc kit I would be willing to sell. I decided that there is no reason for me to go from a 348cc to a 365. I wouldn't be happy so its a 400 stroker or bigger bike. haha
 
whell i guess if im going for a 365 piston from you i gues i have to call L.A. sleeve
Click to expand...


You dont need a resleeve, but that is the biggest the stock cylinder can go before it needs a new sleeve. For the minimal gains you get from going to the bigger bore its not even worth it.


The warrior sleeve like all or most cast iron sleeves are able to be bored up to .80 inch/ or 2.0 MM. There are also three sizes inbetween. .20 over .40 over, and .60 over.( .50 MM, 1.00 MM, 1.5 MM) There are no real noticable gains from going to the biggest, so my motto is bore when you have to. My suggestion .20 over JE, wiseco, or arias. all 11:1 compression or under, unless you want to run race gas.
 
WHATEVER YOU DO, DO NOT INSTALL THE 365 KIT without resleeving your cylinder and actually boring out the cylinder itself. I bought the same 365 kit from vito's thinking it would just be a bore and hone kit but its not. I actually had the cylinder bored out and it was like paper thin. You could flick the cylinder and it would tink badly. So I bought a new cylinder and sent back the piston and got a std. bore instead. I wouldn't suggest going with teh 365 kit. Just my .02 cents
 
If I were you I would get a .430 Webcam or a .450 Megacycle cam. Webcam seems to be the most popular and is like $100 plus core fee on magicracing.com, also you are going to need some high perfromance valve springs or you will float the valves. They are like $70 on magicracing.com
 
whell, i want a cam and piston...i dont have 1000 dollars to spend on getting the top end redone, so i need to know a piston that will work without screwing stuff up, or a place that can rebore for cheap.
 
just go on ebay, you can get a wiseco 10.25:1 for cheap on there. It shouldt cost you much over $300 for the piston, cam, and springs. Just look around until you find the best price.
 
WHAT THE HELL ARE ALL THEESE NUMBERS

all i want to know...will that size fit and is it worth it

and if it wont cost over 300 for all of it fine...i just dont have 1000 dollars to re-bore the engine
 
well, hate to break it to ya, but it would be best to rebore the engine, imo. see, if you go to another piston, you should go one size up. that way, you bore the cylinder out to fit it and get rid of any scaring/grooving in the cylinder. thats what i did on my warrior. if you are going to do something like this, it is best to do it right the first time and spend a good chunk of change, instead of half-assing it and spending even more to fix it. im not saying you would do it half-assed, but just realize that internal engine work and cheap dont really go together unless you do it yourself, but i dont recommend it unless you have all of the tools and are very experienced at it. also, the numbers are the compression ratio. warriors/rappys have 9.2:1 compression ratio. google "compression ratio" and you should find an explaination of it. basically, the higher compression ratio, the more power you can get, but the higher octane gas you have to run. with the wiseco 10.25:1 i can still run 91 octane pump gas, but nothing lower. (you should be running 91 octane stock, but with stock piston you can get away with regular 87, but i would just run 91 anyway) if you dont know what octane is, it is anti-knock. the higher the octane #, the more compression it will take before it detonates. therefore, if you run right compression piston and use 87 octane, it a will knock and probably **** up your motor. search "octane ratings" for a better explaination if you need. basically, just pay up and do it right the first time, or dont do it at all imo.
 
ok thanks...i just need to know what size is best without boring the engine....and i got the whole octane thing...

you said a 10.25:1 will work?...and i wold need to use 91 octaine
 
yeah. even stock it recommends to use 91 octane. you can get away with running regular 87, but its best to run 91. with the 10.25:1 you will have to run 91. either way, if you go to an aftermarket piston, i would go up to the next size from stock and then you need to bore to get it to fit right. it wont be a ton of boring or like a big bore kit or anything (i think it took mine from 349cc to 353cc), but if you use an aftermarket piston in stock size and have grooving and scarring in your cylinder, your rings might not seat right and you will not get a good seal. this will lead to more problems and decreased hp. good luck with your motor mods. let us know if you have any more questions.
 
yes, a 10.25:1 Piston will work and you will be able to run 91. The 10.25:1 is just referring to the compression ratio. He is just saying that you should bore you stock cylinder out like .20 over so there is no scoring or anything on your cylinder wall and you starting out like new.
 
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