PDA

View Full Version : 406?


2001300exguy
04-09-2005, 03:35 PM
How much does a 406 kit help the power is it that noticable. how about with a port and polish, cam, high comp piston, and full exhaust
2001300exguy
04-09-2005, 05:05 PM
ttt
2001300exguy
04-09-2005, 05:59 PM
ttt anybody have one
MXEDUP337
04-09-2005, 08:14 PM
Tommy 17 has one, shoot him a PM maybe he can help you out.
400exredrider
04-09-2005, 08:45 PM
if your gonna spend the money go with a 416
cals400ex
04-10-2005, 01:27 AM
we have built 3 406's, a 416, a 426, and now a 440. the difference between the 406 and 416 is nothing noticable in my opinion if the compression ratios are the same. a high compression 406 piston, a good drop in cam, a good full pipe, and a jetted carb will put you in front of all piped, filtered, and jetted z's and kfx's. it will be a different bike. these mods have been the best changes i have ever made on my bike. i really haven't noticed too much power from a port job but it probably does help a little.
dempsey400
04-10-2005, 07:19 AM
Hey Cal did you notice much difference in the 426 and 440 bore between the other two?
cals400ex
04-11-2005, 10:47 AM
Originally posted by dempsey400
Hey Cal did you notice much difference in the 426 and 440 bore between the other two?


it is really hard to tell. well, we actually don't have the 440 together yet. when i built the 426, it was a few bike lengths quicker. however, on that rebuild i thermal coated my sparks pipe, raised the compression, added a light piston pin, thermal coated the piston, changed from a hotcam to a TC mx grind cam and of course changed the piston diameter 2mm's. so i really can't tell you because this build got several changes than my 406 had. the power shifted from mainly top rpm to mid rpm. i don't know if that is from going with a good midrange TC cam or from going with a larger bore. i have a feeling it is from the tc cam. i did notice more heat, even with a thermal coated piston and pipe. i don't recommend get a 426 on the stock sleeve but others will argue with me all day on that so that would be up to you. with a 440, it is required to have a larger sleeve. if you want a good reliable bike, i would do the stock bore high compression piston to a 416. any of these, including the 406 will produce good reliable power. it is very critical to match your cam to your riding style, get a good full pipe, and jet the carb properly.