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08ex4
05-09-2009, 08:56 PM
im thinking about a 416 big bore kit. what kinds of things do i have to change a i mean i know you have to put the new sleeve and piston in but do you have to get the cylinder honed or does the new sleeve slide right in? what about jetting. i want to keep the stock compression which i believe is 11:1 correct me if im wrong. also will i need to get a different cam.anyway i will greatly appriciate everyones input...thanks guys

zfrank07
05-09-2009, 09:22 PM
i am about to go with the 416 or 426 myself...just tryin to decide which will be best for my riding which is trails mostly.

86 Quad R
05-14-2009, 03:04 PM
the stock compression on those engines are listed at about 9:1.

there is a wide range of c/r's that you can go back with but typically the b/b kits come with 11-11.5:1 pistons.

when doing a b/b you'll need to carry it to a reputable builder to have the old sleeve removed from the cylinder and have the new sleeve put in and chances are it'll need to bored to fit the new larger piston(atleast thats how the 440 kits are). this would be a good time to have the head ported/polished and you may want to get an aftermarket exhaust or atleast a slip-on. an aftermarket cam isnt really needed but is a plus. and you'll also want to get a jet kit aswell.