440 bigbore?

[wolf400]

okay so its about time to rebuild the ole 400 and im looking into the big bores and i dont know witch is better the 12.5.1 or the 11.1 if anyone could help me out and let me know about them or where to find a good deal found a bigbore and you can choose compression ratio and it comes with a wiseco pistion, top end gasket kit ,Namura Cylinder Sleeve & a Stage 2 HotCams cam for 364.95. if anyone could help out and let me know where a good deal is or wat compression ratio to go with that would be awesome!

[Choppers]

I have always heard bad things about namura. Also anything bigger than 11:1 ratio requires race gas normally. My 11:1 requires race gas because of the temps here and sea level.

[togup]

happiness is high compression untill you blow it up ,if you go high comp its best to get head studs and heavy timing chain that 364$ can be the start of some serious money +the machine shop to put the sleeve and studs in, im not talkin you out of it just be ready to spend more for a440 maybe price a 416 or a 426 while your at it

[dubee]

sounds like you better get a 250ex

[extremetrucker]

416, stock sleeve, judge your compression by the type of gas you wanna run, toss a hot cam in. and do the gt thunder studs if you do choose hi comp. i have had a few 440s and regret every one of them. reliability usually goes out the window

[wolf400]

i def need something thats gonna be reliable i don't want to have to rebuild again in like a year, but i want some power out of her.. what was so bad with your 440s?

[bigbad400]

to do a 440 right you really need the heavy duty rod and better valves and a cam and intake and gt thunder head studs and 12.5:1 you will need race gas. 11:1 dont need it but it runs alot cleaner with it. you may be able to get that kit for 350 but you will end up spending 1000 if you want it to be even close to reliable. and namura is good, i had a namura piston in my 440 and she ripped good. the rod went out through the side of the case thow and now its not so good. but its the rods fault not the pistons.

[extremetrucker]

Originally posted by wolf400
i def need something thats gonna be reliable i don't want to have to rebuild again in like a year, but i want some power out of her.. what was so bad with your 440s?
i chalked it up as the sleeve being too thin and it distorts when it gets hot. lets face it, its a 400ex thats already a problem. a 440 will run great for about 10 minutes of hard running, and then you got a round piston in an oval bore, the best i can tell you for a 440 is to get a thicker sleeve (i know they used to make em) and have the cases bored too. or take it out to a 416 or 426 and be impressed how good that runs, or stroke it. and it will pull the world. and like big bad400 stated, a heavy duty rod would be a wise investment, but if you get a stroker, thats included:macho

[togup]

Originally posted by extremetrucker
i chalked it up as the sleeve being too thin and it distorts when it gets hot. lets face it, its a 400ex thats already a problem. a 440 will run great for about 10 minutes of hard running, and then you got a round piston in an oval bore, the best i can tell you for a 440 is to get a thicker sleeve (i know they used to make em) and have the cases bored too. or take it out to a 416 or 426 and be impressed how good that runs, or stroke it. and it will pull the world. and like big bad400 stated, a heavy duty rod would be a wise investment, but if you get a stroker, thats included:macho

yea but they dont tell you is you got to buy the full gasket kit because you got to break the case apart and apair of $80 crank bearings

[extremetrucker]

this is also true, but still worth saving for imho

[bigbad400]

the 400 ex cannot safely be bored to a 440 you have to re sleeve the cylinder. everytime you try it it will fail if you dont. its a big bore its never going to be as reliable as a stock motor, but honda makes the most reliable quad in the industry since 1999 with the 400ex. how is that a problem? dont tell me you ride a z400... waste of time and money(i have one!!!) ride red!!!

[bert400]

I bought a 440 Wesico kit off ebay when I did mine..it cost me around $180 for the kit...which included 11:1 comp. piston, rings, 440 sleeve, and gaskets. Then I bought GT thunder HD head studs and sent it all off to Trinity racing..it cost me an arm and a leg to get it done..it was around 450 bucks to bore out old sleeve, press in new sleeve, bore it out a tad (because it shrinks a little when its pressed in), deck the head, and put in the new studs...yeah I got reemed on price...but then I went with a stage 2 hotcam and 450R carb. My runs like champ and has alot of power now! I would def get a HD timing chain too I have yet to get one...but I have had mine done for about a year now and everything runs good and strong so far..With all that I spent around $900 bucks probably??