Can i run pumped gas with 11:1 compression or do i have to go with 10:3.1? i am building my 440ex and i still need to buy a headder pipe for my exhast i have a Yoshimura exhast but i am going to buy a CT full system. and is a stage 2 hot cam the way to go?

 

You should be fine with running pump gas with 11:1 compression.

 

yes you can run premium pump gas in an 11:1 motor but you may get better performance by adding one or two gallons of 110 octane fuel with the premium to make 5 gallons.i have recently found that 1 gallon of 110 race gas mixed with 4 gallons of premium pump gas (92 octane) makes a very big difference in my wifes 440 as far as overall performance is concerned.i am not familiar with the specifics of the stage 2 hot cam but i would get a cam that builds your power where it will be the most useful for the kind of riding you do.i would try to find detailed information on the cam you are looking at getting and see if it builds the most power in the rpm range that you will use most and that should work well for you.

 

i am running a 10.8 piston with thinner gaskets in my 406. it runs fine on premium fuel, but i have never tried race fuel in it before so i don't know if that would make a difference. the hotter months will give you more of a problem than the colder months. why don't you just get a 10.8 compression piston with factory size head gaskets. or you could get the 10.3 with thinner gaskets which will give you around 10.5. also, i recommend je or ross pistons and not wiseco for the 400ex. the stage 2 is one of the most aggressive drop in cams made. you need to rev the bike out in order to have the power. with stage 1, the power comes on quicker but doesn't let you rev it as far. i ride in open terrain so the stage 2 suits me well. if you were to ride in tight areas, i would recommend the stage 1.

 

the stage 2 hotcam is for bores over 426. so u would want to run it. the only downside is that it's made for speed. so if u ride dunes, u might want to gear down ur quad a bit.