400ex (440ex)

[bulloxerfan]

I have a 02 400ex which I have bumped up to 440 port and polished head yosh pipe stage two hot cam jeted, Well you get the Idea I have heard you can change the carb out to get more power is this true if so how much mod is needed and which carb is the best? Who ever reads this thanks for taking the time to give a hand :)

[rocky_mtn_honda]

http://www.exriders.com/vbb/showthread.php?s=&threadid=409169

then
http://www.exriders.com/vbb/showthread.php?s=&threadid=314423&perpage=13&highlight=carb&pagenumber=1
and
http://www.exriders.com/vbb/showthread.php?s=&threadid=231507
and i must not forget,
http://www.exriders.com/vbb/showthread.php?s=&threadid=143853

[odog]

a carb is a must for a bigbore kit. i have the 39mm fcr. carb. its pricey thou.but well worth it

[Chukkinsod]

I have had both the FCR39 and the Eichner Edelbrock..........both flat slide pumper carbs and work really well. Each one different with tuning. Also another option is a Lectron, I've heard these carbs are the whip , but hard to tune. Most people on this site went with the 450 carb (heck of a lot cheaper hit on the checkbook)

[tri5ron]

Originally posted by bulloxerfan
I have a 02 400ex which I have bumped up to 440 port and polished head yosh pipe stage two hot cam jeted, Well you get the Idea I have heard you can change the carb out to get more power is this true if so how much mod is needed and which carb is the best? Who ever reads this thanks for taking the time to give a hand :) Ok, so now you've gotten all the info reguarding your question about the carb upgrade.

But here's a little word of advise,...
If you put the 440 kit in,...
with a higher than 11:1 compression piston,...

Then you NEED to ALSO have the HD studs installed using ROLL FORMED THREADS.

If you do not have the HD studs,...your bike WILL pull the stock studs out of the case.

It is the most common engine failure, on the 400ex engine, that has been modified.
Resulting in blown head gaskets, oil leaking from the bottom of the cylinder, damage to the stock thread holes, lost power, and lost cash from your wallet.

Do some searching and reading on HD studs on here. You will be saving yourself some headache's and damage to your engine, if you do it now, rather than "trying it out for a little while" without them.

You can consider this as either "good advise", or an "I told you so..." :devil:

[Chukkinsod]

I would HIGHLY recommend the HD studs no matter what set up you have. For $100 dollars installed (GT Thunder)...it will save you a ton of cash and frustration. I wish I would have done it long before I did....ended up having to replace my cylinder because the studs were ripped out one too many times (not repairable). I'm running 12.5:1 and have not had issues since. At the time, it seems like a dumb thing to spend the cash on, but it is probably the most important upgrade out there.

[sab24711]

heat heat HEAT !! got to make it cool to be reliable. stainless steel heli coils work just *** good if not better then the hd studs and a whole lot cheaper. aux oil cooler i strongly suggest, the 4 inch fan is good works well but you cant beat the the extra cooler. if you want a deal (this is for anyone out there) there is a site jaggs oil coolers they make a 400ex oil cooler kit. but i just called and asked for the oil cooler, mounting hardware and oil lines a guy named marv hooked me up! and it cost 185 compared to the 260 they ask for the whole kit. oh don't forget the hd timing chain, aftermarket cam , and good gaskets (necessity). its a lot of work and even more money but its defiantly worth it if you want the thing to run down the road.

if your looking to pump all the pony's out of the system i would go crazy with a carb and mild to wild port and polish.

hope this helped im in the process of getting all that is listed done so if you need any help shout a pm at me later

jer

[coile33]

lectron - tc racing engines if you want to go fast.

[tri5ron]

we've all heard the saying about opinions and certain parts of the anatomy, ...
everyone has them, (including myself).

so with that being said, I disagree with the idea that a SS helicoil is just as good as properly installed HD studs.
The reason for my disagreement is that it is not necessarily the studs that are the problem. Rather, it is the parent material of the engine, (cylinder)and the contact surface area,(thread dia.) of the studs.

Properly installed HD studs, utilize larger holes, (more surface contact area), and are Roll Formed as opposed to cut threads.
Roll formed threads actually condition and strengthen the parent material, increasing the hoop tension of the threaded hole, similar to another process in metal working called "coining".
it is sort of like "case hardening" the inside, and immediate perimeter, of the hole, that is being Roll Formed.

Cutting threads for a helicoil do not do the same thing to the material, and do not result in, or provide, the same properties as Roll Formed threaded holes.

[Chukkinsod]

Completely agree with TRI.......I had SS Helicoils put in and ripped them out as well. You cannot put in the HD studs after you cut in for Heli...not enough material left....so in my case I needed to replace my cylinder to get proper torque settings to run a high comp piston. I single lap drag 300ft, so Temp ususally not an issue, but I am interrested in this add on Extra cooler..........anyone with a link or phone #. Hate to add weight, but a cooler motor will run more efficient. Run 110 so that will help reduce temps, but also want to try E85. Thanks for the info

[sab24711]

http://www.setrabusa.com/jagg%20files/jagg%20pages/jagghome.htm

left side e-mail jaggs and ask for the cooler parts

if you do buy it and looking to get the best performance out of an extra cooler you need to do the fst oil cooler

http://webpages.charter.net/tandrus4700/400exCoolerMod.pdf

same principals but jaggs coolers are just a better looking cooler rather than the ugly trans coolers a lot of people use. plus it blocks a lot of flow to the engine you still need air to pass an air cooled engine.

i never had a problem with ss coils and i have done it to mine and to a few fellow friends quads and they have all lasted to this day . i guess its just the fact that i like to do things on the cheap, oh well whats wrong with saving a few bucks (strip club!)

[Chukkinsod]

Thanks for the info.......i'm a little confused though, your sayin the Jaggs cooler is ok, but the FST cooler (running into the head/clutch ) is the way to go......It seems like that is the best way to go. Couldnt you run the JAGGs cooler in the same fashion? Either way is very pricey. Does this replace the factory (small cooler) or just additional. Wish someone had a liquid cooled conversion.....make things a lot easier

[sab24711]

well adding any extra oil cooler can only help but supplying freshly cooled oil to the top end is the best thing you can do so far.the oil goes though the cooler then to the bottom end and works it way up, so by the time it gets to the head it is heated and broken down. a lot of people don't like the fact you need to drill and tap so they just buy the fan. it does not replace the stock cooler just adding a new one. thats what i was saying before using the jaggs cooler in place of the trans cooler that they use in the fst mod.and a liquid cooled conversion would be very very pricey you would have to have an coolant pump, chambers in the engine, radiator and lines. and so on at that point you should just buy a new engine.