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416ex Build Questions...

2598 Views 1 Reply 2 Participants Last post by  jimcarrier
Hey braaapers, new to this forum, got tired of searching and searching on different threads so i figured I ought to join one. I'm building a 2003 416ex 11.1 weisco piston, Stage 2 Hotcam, heavy duty crf450 chain, kibblewhite springs, weisco valves, 16t sprocket. Engine needs piston rings, starting to smoke more than usual I've noticed.. The bike already has big gun rev box and full exhaust. Not quite sure if that big gun kit comes with jets, but anyway, I do a lot of field riding and racing, every once and awhile we will hit the trails, my question to y'all is. After i do all this, in addition to adding the 16t sprocket do you think that engine build will make me feel like I'm gaining anymore low end power even with the 16t sprocket. I know my top end will increase but not sure bout how much low end, and while I got it apart should I go ahead and put new head studs in it...... Thanks in advance....
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11:1 will sure give a good gain over stock compression, you might want to have your head or cylinder decked to have a good 40 " of squish... or you are mostly going to have in the 9.1 compression range.

ive ran 13:1 piston on pump gas actually 12:1 because of the deck height. with a good porting and cam was enought to keep with 450 on the track.. everything with stock stud, never pulled one at even torqued to 40 lbs ! BUT most 400ex have them pulling out. so i would go with gt or any thing with bigger botom threads.

you dont need to go new valve, and bigger valve spring, mostly going to stress everything more. you could even put a hot cam 3 witout any trouble.
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