white bros e-series slipon help

[jrmy]

I just bought a 2002 400ex bare stock, just put some tusk nerf bars on it last week. I am going to order a white bros e-series s bend slip on this weekend. Do I need to order anything else a long with it like a K&N air filter, jets, etc? will all that be required or can I just slip the pipe on and go. I found a article about the pipe saying you could switch the number of discs in and out on the pipe to make it run leaner or richer (no clue what that means), ive read all that bout the spark plug needs to be a brown color. Just looking for some input, the pipe is only 193, wanted to make sure I had everything before I went to changing stuff around cause im not really looking to put that much stuff on it considering im only gonna be trail riding, road riding to get to trails, and maybe a little hill climbing.

Also does anyone know the dB rating on this specific pipe?

Thanks in advance

[GPracer2500]

An air filter is a good idea. K&Ns flow well but aren't the best for dusty conditions. UNIs also flow pretty well but are better in dusty conditions. Choose accordingly.

Lean means too much air and not enough fuel.
Rich means too much fuel and not enough air.

Yes you will want to rejet your carb with a slipe-on pipe and especially with a slip-on and aftermarket filter. Pipes and filters allow more air to get into and out of your engine. But your stock carb jets will only provide enough fuel for the amount of air that flows with the stock intake/exhaust configuration. Actually, the stock jetting barely delievers enough fuel for a stock bike--they come pretty lean from the factory, especially in cooler conditions and lower elevations.

With a filter and pipe (or just a pipe) you can get away with only changing the Main jet. It is very easy on the 400EX because access to the carb is excellent and access to the main jet within the carb is excellent.

Turn off the gas and drain the carb (there's a little flat-head screw on the left side of the float bowl towards the bottom that drains the bowl). See that 17mm bolt on the bottom of the carburator? Unscrew it. On the other side is a brass jet directly above where you removed the 17mm bolt. Take a 6mm socket (deep socket or swivel head socket works well) and unscrew it. Replace with a larger sized jet. DON'T overtighen it--it only needs to be snug.

The stock main jet is a 148. What size should you use? The correct jet for you depends on a lot of things--tempurature/elevation/humidity (all factoring into air density), type of exhaust, type of air filter, airbox configuration, etc. Even how much you've oiled your air filter will affect air flow enough to make a difference to a discriminating tuner--most won't notice those small changes though.

Buy several jets (use Keihin brand jets) and experiement to find the best results. I might suggest having a 155, 158, 160, 162, and 165. You'll probably be somewhere in that range--I'm guessing.

Good luck and remember that jetting is moslty a trial and error process. Once you get good at distinguishing between lean running conditions and rich running conditions then your guesses will be closer from the get-go. But, at first it's mostly a matter of trying a jet, running it and watching for how the bike runs (remember that the main jet only comes into play at 3/4 to full throttle--RPM is irrelevent). Then try one size in one direction or another and see if it's better or worse. If it's better than go one more size in that direction...you get the idea.

[Honda#4]

i have a wb slip on and i didnt rejet or anything i have great low end power the pipe is around 96 dbs.my plug was always black and wet and when i put my pipe on it was perfect .

[04'400ex'er]

You definately need to rejet. You could pick up a UNI filter pretty cheap. I would order a 42 pilot, 155, 158, 160, 162, 165 mains. You will need those jets and will be better off just having them for future notice.

42 pilot will be spot on if you remove the airbox lid, and I would just start with the 155 on the mains. The mainjet only takes 5 min to change on the ex so its no big deal to dial that in. Im gonna say you will be right on with the 155 but 158 or 160 might be what the bike takes. Just keep richening the main up until it boggs, then back down a size and go.

[jrmy]

OK, I guess I will just order the pipe, UNI air filter (its usually very dusty here in west TN), and those main jets that you suggested. Any suggestions on where to order the Keihin jets?

[underpowered]

Originally posted by jrmy
OK, I guess I will just order the pipe, UNI air filter (its usually very dusty here in west TN), and those main jets that you suggested. Any suggestions on where to order the Keihin jets?

wherever you are ordering the pipe from should be able to get the jets for you as well.

[jrmy]

almost all the jet kits dennis kirk carries are dynojet :(

[underpowered]

Originally posted by jrmy
almost all the jet kits dennis kirk carries are dynojet :(

Not a kit, just the jets. They should come in a like a 5 number range. single jets and a jet kit are two differnt things. I believe DG has some, but dennis kirk should sell Kehin jets as well.

[flauge]

i think wb includes their own powerfilter with the pipe.but it might just depend on where you order it tho...

[Honda#4]

i got a power filter with mine.

[Hondaman90]

Mine came with a filter too!

[Honda#4]

i'm glad i bought my pipe when i did cus they r $300 from rocky now and i paid $270 for mine plus free shipping.

[miller821]

Originally posted by Honda#4
i'm glad i bought my pipe when i did cus they r $300 from rocky now and i paid $270 for mine plus free shipping.
I got mine for $215 shipped, with power filter. Like everyone else said, experiment with jets, 155 is what I got and it works great. Also if you get a new air filter, or keep the old one, drill some holes into your airbox lid. On the back of it drill like 30 small holes across it, that way water won't get in easy, and you'll get more air flow. Or just take the airbox lid off, but since its dusty you might not wanna that.

[04'400ex'er]

Here is where I order my jets from... http://www.magicracing.com/view_category.asp?cat=172 and they have the pipe you are looking for for $250. I have always found them to have very reasonable prices in the past.

[JOEX]

Originally posted by jrmy
OK, I guess I will just order the pipe, UNI air filter (its usually very dusty here in west TN), and those main jets that you suggested. Any suggestions on where to order the Keihin jets?
C&D Racing, one of our site sponsors can get you the jets.

I bought my 400ex used with the WB E-series w/12 discs, K&N and a 150 main jet. It ran great with that set up, used the original plug for two years:)

[jrmy]

wow thanks for all the input guys. I just ordered the wb pipe, and UNI air filter off dennis kirk for 193$ (the pipe), their having a closeout on them so I just went ahead and ordered one while they still had some in stock. I'm randomly having problems with my clutch now, started a thread called "Clutch Sticking?" about it. So hopefully by the time the pipe gets here I can have that fixed, lol.

[my250ex]

i found this thread helpful also. i live in massachusetts at roughly 200-300ft above sea level. can i get jets from a local dealer? its bone stock right now but i am also ordering a wb pipe. what size jets do you reccomend. stock is 148 right? i think i should get 150-155 sized jets. does that sound ok? i am going to do what that other guy suggested... keep going up jet sizes until it sputters, then back off one size and check the plug. am i going to have to mess around with the needle at all?

[miller821]

Originally posted by my250ex
i found this thread helpful also. i live in massachusetts at roughly 200-300ft above sea level. can i get jets from a local dealer? its bone stock right now but i am also ordering a wb pipe. what size jets do you reccomend. stock is 148 right? i think i should get 150-155 sized jets. does that sound ok? i am going to do what that other guy suggested... keep going up jet sizes until it sputters, then back off one size and check the plug. am i going to have to mess around with the needle at all?
Yes stock is 148... And 150 or 155 sounds pretty good... I got a 155 in mine, and it works perfect for me... But try around yourself and see.

[my250ex]

it says in the description:

"Jet adjustment facilitated by the tuneable end cap assembly"

what does this mean? does it really work?

[miller821]

Originally posted by my250ex
it says in the description:

"Jet adjustment facilitated by the tuneable end cap assembly"

what does this mean? does it really work?
For one, it means you can add or take out the discs, depending on what one you want to do.... And, and i'm not for sure on this, but it kinda sounds like its saying that, the different amount of discs means different jetting.... Maybe, but thats what it sounds like if you know what I mean.

[my250ex]

what are the discs for

[miller821]

Originally posted by my250ex
what are the discs for
Well, if you add discs, your letting more air escape, causing more it to be a little bit louder.... The less discs you put in, the quieter, and more backpressure, which gives you a little bit more bottom end then putting them all in..... Personally I would run all of the discs, unless you live somewhere were noise is a factor, cause I can't tell a difference in running all 12 or just running 4 except noise... But I run it wide open with no disc or spark arrestor, and its pretty loud, but I like it, and can notice a substantial increase.

[Honda#4]

yea i notice a increase on top end when i put all the discs in on mine same with bottomend,it is louder with all the discs in.yes by taking or putting in the discs it does do different jetting the more discs u put in the richer it is.

[guinness77]

With my White Brothers E-Series pipe, I started with 4 plates. My bottom end (accleration) was fantastic. But my top end only went up a bit (4-8MPH). So I went to all plates for a comparison. The low end was not as impressive, but there was more top end (9-13)MPH. I finally settled on 7 plates. I wanted accleration anyway. The pipe VERY nicely complimented my Power-up kit for the carb (by Moose Works) and K&N filter. The Moose jet kit is engineered for more low-end increase anyway. And the K&N helps everything. I'm installing A Sparks Racing 6-degree timing advance key next week and in a year or two I'll bore to a 416 (not stroke). That'll REALLY give it better low end.

What really nice about the E-series is you can adjust it for the type of riding YOU want. If you're into long distance racing you can adjust it for more top end. If you're into sprint racing or duning you can go the other way. With out this adjustability, you would have to figure out what kind of performance you wanted and then bought the items that complimented what you want. (You can still do this 'ya know. In fact, all the non-tuneable exhausts impart their own characteristics on the total motor system.)

[exrider23]

Is the s-bend required with the stock header?

[Honda#4]

i'm currently running 6 discs with stock jetting and its great i got great lowend and topend power i'd say the sweet spot for a e-series is 6 or 7 discs if u want both bottom and topend power.

[400exbilly]

I have a white brothers e series pipe and i took of all the reeds and block off screen and just put the cap back and you will get some more power and the good thing is it will be a lot louder i can hear mine like a half a mile away? :macho :huh :huh :huh

[miller821]

Originally posted by 400exbilly
I have a white brothers e series pipe and i took of all the reeds and block off screen and just put the cap back and you will get some more power and the good thing is it will be a lot louder i can hear mine like a half a mile away? :macho :huh :huh :huh
Ya thats how I run mine, and I love it with that set up..

[CGriff]

This is my first time replying on these forums and I must say theres a lot of good info on here. I got an E-Series S bend a month ago and ran it with 12 discs and stock jetting up until this week. It's in the shop right now getting a valve adjustment and rejetted. I'm curious to see what the difference would be. It worked great befor and it will work even better now.