bore kits

[Lamont400ex]

I have a 2003 400 ex that is ready for rebuild. I am looking at all my options here and want some advice from all the members. I use my bike for trails pretty much all the time and am looking at wether i should go with a bore kit or not. I want realiabilty and power. I have heard the 440 kit is not as realiable but have heard many good things about the 416 and 426. What is everyones opinon on this? Next is I am from Canada and getting the parts up here is hard I am willing to order from whever so where does anyone sugest? and finally what extra parts are required to do any of these kits? I would like to keep my costs down. Thank you

[sixer3]

i've seen properly tuned 416's smoke unknown 440's just depends on how well they are tuned and put together, my suggestion is a 416 and provided you already have a jet-kit, filter, and pipe, make sure to get the top-end seals, and a hotcam other than that the machine work and your ready to go, pay attention to the compression you buy, higher compretions at bigger bores may require larger head-studs which will also need to be machined into your head, better safe than sorry, a piston kit off ebay isnt too expesnive, you get the sleeve, seals, piston, and sometimes a cam for about 250 checkj out ebay, i recomend the JE or ross pistons and port work also helps a tone!, all the machining sounds pricey but its not too bad, good luck, and ask your local dealer's service shop if they do that kind of work and how much it would be

[hard one]

To get a fast machine it all depends on what you put in to it and a big bore isn't every thing a good came selection can make it a scary fast engine or a decent one and you want as much air coming in as exhaust is coming out!