440 questions

[unlucky13]

Ok so im looking to bore my 400 so im not completly murdered by 450's I have a hot cam stage 2 and 450r carb and im putting a 450r fan on my oil cooler what's the pros and cons of going 440? I mainly ride on gravel roaxs some trails and the highway is there a way to make them last?

[ridehonda400ex]

A 416 or 426 will rev a lot faster than a 440. 440's have good torque from what ive read. Get an 11:1 416, and with the stg 2 hc, the 450r carb, and the oil cooler. You would have a fast machine, and be reliable still. Then if you go 416 you still have an extra bore on the stock sleeve for if something goes wrong. And if you dont already, get a pipe to let it flow better.

BTW please stay off the highway. It gives people more reason to B!tch about quads and more reason for more laws against them, Thanks;)

[unlucky13]

Around here one of the cops told us we need do work on our donuts lol and I've heard they have to bs resleeved for a 426?

[CJM]

416 and 426 do not require a new sleeve, 440 does.

In all honesty what makes power isnt displacement considering your not going up by very much. A 416 is really closer to a 413, 426 is 423 and a 440 is actually 435 (understand the actual engine size is 397cc's-not 400cc).

What will give you the power is a higher compression piston. Downside is heat created due to the higher compression and in some cases the need to run 100+ octane.

A 416 and 426 really make no difference in power-its quite minimal to say the least if you were to build 2 the same but one of each displacement.

That being said, if you want power you build it like this:
-87mm piston (416) 10:1 or 11:1, anything higher such as 12:1 and so forth needs 100+ octane. 11:1 is the highest you can run on 93 octane.
-Stage 2 or similar hotcam to take advantage of the power
-450r carb off an 04-05 (look in the sticky in my signature for more info about these carbs)
-A good slip on or full exhaust
-GT Thunder heavy duty head studs. They arent truly needed but since the EX is air cooled the exhaust studs can pull out due to heat. This remedies the problem
-CRF450R 2002 timing chain, this needs to be done, stock chain is weak and this fits and is MUCH stronger
-4" spal puller fan mounted to oil cooler (to help cooling)
-Not needed but good to have-oversized oil tank either CFM or UM.
-EHS Outerwears filter lid, KN lid or no airbox lid
-Take stock header if you use the slip on and grind the welds inside the end of the header where it mounts to the engine for better flow
-Port and polish is always nice as well
-Cometic brand gaskets (base, head and valve cover). They are thinner and raise compression a bit over stock. Stock gaskets are very thick and hold back on compression.

You can do it all for about 600-700 bucks or less if you find deals on stuff and can do your own work. I have pretty much that setup and it pulls VERY hard. It aint no 450r but its dang close-racing they might beat me by a length or two, considering they dont have a much more advanced water cooled engine thats saying alot for an EX.

[hondarider421]

or u can buy a motor built for 850 and its promissed to out run 450s slightly modded ones at that i have a 440 big bore 4 mil stroked stg 3 camed ported head and bike has reverse ill sell wit oil tank extra oil cooler and air shrouds for 850 motor just been refreshed i am parting it out cause i built a 450r for motocross pm me if ur interested