What can i do to get more power

[PaRedneckRiders]

Ok well im rebuilding my 426ex and while its semi together i want some ideas of what else i could do that would give me good power at a good cost
So im rebuilding it now and it will have
wesico 11:1 426
Kibble white valves
and a white bros. r4 slip on
Im thinking about getting a cam prob a stage 2 because my buddy has one that he said he would sell me

Im juz thinking what else can i do, I dont think i can run an advanced timeing key because its a big bore with higher comp.
juz give me some ideas of how to get more lower and mid range power and a lil more top end because i mostly ride in the woods

[honda400ex2003]

I would suggest trying out the 3+ degree this would be a bit better, it may still predetonate with 91 octane though, 93 may be ok though, if it is good stuff. I would suggest a port and polish to clean up the ports a bit, along with doing some grinding on the header to get it flowing a bit better or run a full header. that will help out the flow a bit more with the stage 2. a monster coil to help out with a bit better spark and a bit better throttle response would be nice, 450 carb maybe, open airbox lid, other than that, if i think of some more, i will post it up. that would make a 426 about as good as it could be if you did all of that. steve

[PaRedneckRiders]

Well around my area there aint much 91 octane its all 93 so it might work
ive herd u had to run 100+ octane with the +3 key

How would i grind the welds in my header down?

I will prob end up running it with no airbox lid anyway so ya

Then a lil a lil later ill prob get a cam

And as for the port and polish i could do that when i get a cam but should i have someone else do it or could i do it myself?

What would i have to do if i did it myself?

[PaRedneckRiders]

I found a 400ex cam on ebay
Its a TC GNCC
its used but they say its still very usable
What do u guys think

http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&item=320506397186&viewitem=&sspagename=STRK%3AMEWAX%3AIT

[honda400ex2003]

Originally posted by PaRedneckRiders
Well around my area there aint much 91 octane its all 93 so it might work
ive herd u had to run 100+ octane with the +3 key

How would i grind the welds in my header down?

I will prob end up running it with no airbox lid anyway so ya

Then a lil a lil later ill prob get a cam

And as for the port and polish i could do that when i get a cam but should i have someone else do it or could i do it myself?

What would i have to do if i did it myself?
just do some searches, there is a big thread with pics and everything of grinding what you need out. it is the inside ring on the pipe where it was welded together at the factory. If you dont have a cam yet that would be a beneficial thing to do to get more power from a 426, you gotta let it breathe. Stage 2 or another similar would be great. Do a search for 400ex specs or go to the FAQ section and find the specific comparison on cams for the 400ex. sorry i am just getting ready to leave or i would find the links, it wont take you long though. steve

[Muzzgit]

Stage 2 hotcam.
Port and Polish.

After that, get a bigger quad!

[PaRedneckRiders]

no prob man i will seach and c what i can find
Thanx for the ideas

[PaRedneckRiders]

Ok so ive herd many things about shaving weight off the bike and im all for that
ive herd about removing the snorkel, cut fenders (there already cut)
and some other things well thats not my question

Ok ive herd about ppl shaving there flywheel,
What does this do, does it juz shave weight off of the quad or does it effect performance
If it does how does it effect it and what would it cost to do it
Also would u recommend it for me
I do mostly woods riding like i already said but i want as much power and speed out of my quad as i can

[rcatvrider]

Lightening the flywheel is not really to lighten the quad, it creates less rotating mass inside the motor. This makes it rev up faster but is more prone to stalling, especially in a woods application since there is less momentum inside the motor to keep it moving at lower rpm's.

[MidnightBlade]

id get an adjustable dynatek rev box. you can change the timing, rev limiter, and a heck of alot more. i think they are like $150 or so on ebay

[PaRedneckRiders]

so in like a gncc application a lightened flywheel would have both its pros and cons
Pros: revs really fast and would increase acceleration
Cons: more pron to stalling in say a tight turn where your not on the throttle as much

[PaRedneckRiders]

is there anything that i could do to prevent it from stalling when not hammering on the throttle if i would lighten the flywheel?

[honda400ex2003]

Originally posted by PaRedneckRiders
so in like a gncc application a lightened flywheel would have both its pros and cons
Pros: revs really fast and would increase acceleration
Cons: more pron to stalling in say a tight turn where your not on the throttle as much

correct, in some applications it works great, others like xc not so much since the flywheel helps to keep the motor turning. honestly there is not too much you can do except ride a bit different to ride the clutch a bit more and make sure you can get into a low enough gear not to let it stall out. this would require gearing down in some cases depending on how much is taken off of the wheel when cutting it. The more that comes off the less weight to help "lug" it with the momentum of the wheel so the harder it is to keep it running. the ideal situation would be to find a perfect spot to take some off and still be able to have the lugability lol Made that one up just now, I am proud of that. lol. that you want for xc and tight woods applications. I would say that around 8 oz could come off and maintain a decent amount of both but once you go into 12-16 oz or a bit more it would start to become too light for woods riding. just an idea of it though, some guys love them others hate them. this is one thing about mods lol just like a sparks key, which exhaust is best, and which one makes the best power. lol. it is all in the eye of the beholder. I feel that my 416 has plenty of low end and can still run good up top so i am happy. I plan to do some experimenting with it to see if there is any setups that are better but in all reality it could make it worse by moving the powerband too high for where i like it. It really depends on the riding you are doing, if you plan to do xc on tight woods trails gear down enough for the application, this would in turn make it rev faster anyway but will maintain the low gear crawling but would take away top end for the longer runs. Alot of variables have to be concerned for the best setup, this is why racers have many different setups they can run, with different pipes, gears, tires, cams, lots of things. It all has to be taken for the best. For someone who is just bombing around the woods on their land it is not as critical lol. I would suggest possibly cutting a flywheel as a last thing if you want it to rev faster. the 426 is said to be the fastest revving bore of all of them with the right setup. finding that setup may include a correct cam and such. I hope i didnt repeat anything, i was doing a few things inbetween typing lol. sorry if i did, steve

[JOHNDOE83]

The force is strong in you steve. lol.

[honda400ex2003]

oh yeah baby lol. thanks bro, steve

[PaRedneckRiders]

ok well ill break in the new bore then prob go back and get a cam
and mayb get it ported and polished juz to clean it up

Then if i still want more ill start cutting some weight from the flywheel

Ill see what other excess weight i can remove from the quad

i dont gncc race but i ride trails that very alot in the terrain
anything from nice open trails to tight technical trails and when i ride ppl on bigger quads 450, 660, 700 etc
i want to be able to pass them in the tight technical stuff and stay with them in the open trails
that the whole reason i went back to a 400 from my 660 raptor

I like the feel of the 400, it seems to fly through the woods really nice and is really balanced and easy to ride wheelies with

im kinda on a budget to get it all back together so it will run and run pretty good for only being a mildly modded 426

[honda400ex2003]

I think you will be pleasantly surprised how well your 426 will run against the 450s and such. You will be able to walk past the 700s in the woods and they will be stuggling to catch you by the time they get out of the woods and you are across the field already. lol. steve

[rcatvrider]

Ya, imo the woods is where the ex can still hold it's own to this day. When geared right it has tons of torque and with a simple 150 dollar set of shocks it handles quite well.

[PaRedneckRiders]

ya man haha thats the way i like things

I would really like to get into gncc racing but idk where i would have to start and what i would have to do to get ready

but im really interested to c how this thing runs

then mayb ill do some research on gncc racing to c how i could get into it

[honda400ex2003]

you need nerfs, kill switch and a number lol. then find out where to go and you should be able to get set in the right direction. I would check out the racing forums and see what they say about it. Even pappy or someone may be able to help you out. steve

[PaRedneckRiders]

well im set then haha well pretty much anyway
i would juz need a number and a theater switch

I would need riding gear to

but i think it juz sounds like something i would b good at what other mods do u think would make this thing excel compared to other quads in the woods?

[honda400ex2003]

with the stuff you want to do there wont be too much left to do to it. drop down to a 14 and that is about it. leave the flywheel alone, monster coil or dynatek cdi as listed, the stuff we have said is about all you will be able to do to it relatively cheap. once you have that stuff done you would have to stroker and higher compression to get any more competitive. steve

[PaRedneckRiders]

ya id like to juz run it once or twice to see how it holds up compared to other quads that prob have more mods and i would rather stay away from a stroker well at least for now anyway

ill do some research and c what i can find out and what class i would have to race etc

[honda400ex2003]

400 class C is my prediction lol. if there is such a class i will be shocked. steve

[PaRedneckRiders]

ya ill check and let ya no if you were right

[honda400ex2003]

http://www.exriders.com/vbb/showthread.php?s=&threadid=432697&highlight=gncc+info

http://www.gnccracing.com/

these will be your best info sources.

http://www.gnccracing.com/pages/2010-gncc-classes

this one has the classes.
steve

[honda400ex2003]

your age class C 200-open would be a good one to run except you will have some 450s in there and such, there are some theres also that would be good to enter too. steve

[PaRedneckRiders]

ok i looked at the class link and
i cant find anything that i could be legal for
As of now i wouldnt b legal for the 200-open C class
im only 14 as of now and will b 15 in august

the only one i think i could race is
Sport (15+) 201-400cc

then again that site is showing mostly races in the southern US
im a lil more north being in PA

[PaRedneckRiders]

ok any other ideas on adding power?
any things i could do to still run 93 pump gas if possible or mayb juz mix 93 wit a lil bit of race gas

i will still get a cam and when i have it apart i may get i ported and polished

If i pull the head off after the motors already broke in is it gona hurt anything
like would i need new rings or anything?

is there anything i could do like get a different clutch that would help it and wouldnt cost a ton of money

It may seem like im cheap but im juz trying to pull as much power out of this thing as i can on a somewhat limited budget

If i had money to dump in this thing i already would have dumped it into it haha

[honda400ex2003]

Originally posted by PaRedneckRiders
ok any other ideas on adding power?
any things i could do to still run 93 pump gas if possible or mayb juz mix 93 wit a lil bit of race gas

i will still get a cam and when i have it apart i may get i ported and polished

If i pull the head off after the motors already broke in is it gona hurt anything
like would i need new rings or anything?

is there anything i could do like get a different clutch that would help it and wouldnt cost a ton of money

It may seem like im cheap but im juz trying to pull as much power out of this thing as i can on a somewhat limited budget

If i had money to dump in this thing i already would have dumped it into it haha

All of the cheaper items to do have been listed, oh wait, get a 42 pilot put it in your carb and take your assembly out for the choke. 450r carb, p and p, stage 2 cam, full header, filter, open air box, timing advance. that is around 500-600 bucks for all of that unless you get some used stuff somewhere. Add a hinson clutch too if you like not a power adder but can help to keep it from slipping. The stock one is fine, actually quite good in fact, but it may wear a bit faster with a 426. the only thing you will have to do if you take the head off is get a new gasket. although there should be no need to do anything with taking the head completely off, the cam can be changed by just taking the cover off of it. other than that, enjoy your 400ex for what it is lol. gear it down to make it feel like it gets going faster but will go slower. steve

[rcatvrider]

Do you have shocks yet? That will certainly make you faster in the woods.

[PaRedneckRiders]

ok man thanks
im working on getting either a set of 450r shocks or mayb a nice used set of elka or pep

If i wanted to port and polish it i would have to take the head off
so when i get a cam ill juz go head and get it ported and polished

[PaRedneckRiders]

ok so this weekend im going to pic up some more parts (front rims, tires, and one a-arm)

This guy has tons of parts for many different things

Should there b anything i should look for,
im thinking about asking if he has a set of 450r shocks and a 450r carb
mayb another flywheel juz so i could have an extra one so i could shave the one and have a stock 1

Anything else i should look for mayb a cam but extra parts are always nice to have

[-TheDude-]

all of those parts are worthless in an xc race if you dont have good SHOCKS, and im not talking just stock 450 shocks im talkin 450 rebuild/revalves and rear shock done too, if you cant take the bumps, that fast engine isnt gonna be used
SHOCKS SHOCKS SHOCKS

[PaRedneckRiders]

ya man i no haha thats not a big deal ill handle the shocks like i said ill either get a good set of 450r shocks or a nice used set of elka or pep

[PaRedneckRiders]

still looking on ebay for a nice set of 450r shocks

going to get a 450r carb hopefully soon

will have a cam probly after the 24th of this month (gona be the big test for the 426 at tri county atv in heilwood PA)

got a couple sets of razr rear tires and just bought new fronts

im still debating the +3 timing key (because i dont really want to have to run gas any higher than 93 octane)

i completly scraped the idea of shaving the flywheel because i dont really think its worth it

when i get a cam and go to put it in i will deffinitly have it ported and polished to

do any of you guys have a 400ex that has a wider axle or a-arms??
if so do u like the way it rides compared to stock

and would u recommend spending 200$ for a g-force +2+4 axle
and about 600 for a set of lsr extended a-arms
or mayb a set of Fullflights

What do u guys think