I was thinking about boring my quad .040 over when i fix up my quad this winter. My friend told me that Raptor 350s have chome sleeves,and they cant be bored out,then he told me that if i did bore it out it would always over heat. I was wondering how true this is. Any input would be great. Thanks!!

P.S-- Would it be reliable(im getting an oil cooler too)

 

why do you wanna bore it? you don't get very much power from boring at all

 

Yeah, there should be no reason to bore .040 over on a year old quad. The performance gain will be minimal for the money you will spend. You'd be better off putting cams in or a higher comp piston.

 

yeaa deff get the piston or cams beofr eu bore, i have a racing piston in my warrior, man that made a difference

 

What does .040 equal in cc's? Just curios

 

i think its 4 ccs bigger i believe your suppose to move the decimal over 2 spots

 

ok,so where can i get a high compression piston?? and what would one cost?

 

lots of companies make high compression pistons, but I would go with a wiseco
I haven't priced high comps yet but I don't think they're much more than the standard pistons.

The thing your friend told you about chrome sleeves and not being able to bore it is made up though. He's either bull$hitting you, or someone misinformed him about this. and just .40 over would never cause enough difference to feel in power, it's not a performance mod

 

thanks,i kinda figured he was b.s.ing me. I think im going to go with the high compression piston.

 

i would suggest that you put a good big bear adapter oil cooler on it before you do the high comp piston. The stock warrior/rappy350 motor can overheat under harsh conditions, and with a high compression piston you increase that risk greatly. The yfm350 transmissions also have a tendency to act up when they get hot, so the oil cooler is a worthwhile investment. If you keep an eye out on ebay you can get all the parts you need for about $100, as opposed to about $180 for new parts.