05' 400ex All Stock vs. White Bros. E-Series Full

[Mobile Dyno]

Here is some 400ex info. This is a bike that a customer brought to me to install & tune some mods on. It is an 05' 400ex All Stock. I ran this All Stock except for 18" Dyno tires. Mods are:

White Bros. Full Exhaust, E-Series (ALL Discs installed)
Dynojet Kit
Whit Bros. Filter
No AirBox lid

**Final Jetting:**
160 main
3rd from top on needle
3 out on mixture screw

This test was 1hr apart from the best stock run, so the results are SAME DAY!!!

:rolleyes: Here you go for All You guy's running E-series

[Mobile Dyno]

Tq

[Mobile Dyno]

Over Speed...Remember 18" Dyno Tires

[Mobile Dyno]

:D

[Mobile Dyno]

The Big spike you see at the start the Accelerator Pump Not keeping up.

160 Dynojet main at 400ft elevation:D

[krt400ex]

so u only gained a half a horse??:huh

i think a 160 dynojet is a bit too rich.

i wouldn't go bigger than a 160 Keihin

[Mobile Dyno]

If a 160 is to rich then why would I go up? This is with the lid off.

[krt400ex]

u said u were running dj jets. a 160 dj is alot richer than a 160 Keihin. i would lean it out, not go up

[Mobile Dyno]

a 160 dj is close to a K150. There is No need to upjet and I would not go leaner unless you are running the Lid...with a stock Motor. I haver the next round for this 05' coming up. I added a 11:1 compression Stock bore piston, and a 450 R carb:devil: .

[krt400ex]

go here to see a chart

jetting chart (http://www.exriders.com/vbb/showthr...015#post2382015)

the dj 160 is equal to the Keihin 177. a 177 is way to rich for just a pipe

[krt400ex]

sorry link didn't work. do a search for a thread entitled

Sorry But............

to see what i'm talking about

[Mobile Dyno]

dude, I have my own chart and a 160DJ is close to a 150 Keihin & Makuni. DJ #'s are bigger. I have also tested this chart and found the same info on A/F. The one you have is Wrong. I have replied in your thread to help you out and you keep trying to tell me I'm wrong. I know these differences in jet companies and know how they are measured.;)

[bwamos]

That dynojet chart is out of whack. Someone fabricated that chart from their butt, lol.

DJ's are rated on bore diameter.
Keihins are rated on flow.

(I beleive)

They aren't going to progress at the same rate..

[krt400ex]

Originally posted by Mobile Dyno
dude, I have my own chart and a 160DJ is close to a 150 Keihin & Makuni. DJ #'s are bigger. I have also tested this chart and found the same info on A/F. The one you have is Wrong. I have replied in your thread to help you out and you keep trying to tell me I'm wrong. I know these differences in jet companies and know how they are measured.;)

i was trying to help u not jsut tell u that u r wrong. whatever u say. i'm done arguing

[400eXr1d3rZ]

Krt400ex, Mobile Dyno knows what he's talking about. E-series really isnt too great of a pipe, compared to HMF, look at the other dyno chart he has on HMF. Its working with the jetting he has, so thats good, what color exactly was the plug if you had looked, Mobile Dyno?

[GPracer2500]

Originally posted by 400eXr1d3rZ
...what color exactly was the plug if you had looked, Mobile Dyno?

I'm almost sure he hasn't looked because there's no point when when you've got a dyno and air/fuel data at your disposal.

Furthermore, only a brand new plug properly "colored" with a WOT pass is going to give you meaningful information about the main jet (and old plug tells you very little). And even then, I bet 95%+ of people who think they know something about performance tuning using plug readings are gonna look at the plug and say, "Whoaaa, that's WAY too lean--look at it, it's still white!" because they don't really understand how to read a plug.

Almost everything most people think they know about plug reading is for lawn mowers and commercial mechanics diagnosing engine problems--NOT performance tuning.

If you want to know more, see my comments at the end of THIS THREAD (http://www.exriders.com/vbb/showthread.php?s=&threadid=237664).

[krt400ex]

Originally posted by GPracer2500
I'm almost sure he hasn't looked because there's no point when when you've got a dyno and air/fuel data at your disposal.

Furthermore, only a brand new plug properly "colored" with a WOT pass is going to give you meaningful information. And even then, I bet 95%+ of people who think they know something about performance tuning using plug readings are gonna look at the plug and say, "Whoaaa, that's WAY too lean--look at it, it's still white!" because they don't really understand how to read a plug.

Almost everything most people think they know about plug reading is for lawn mowers and commercial mechanics diagnosing engine problems--NOT performance tuning.

If you want to know more, see my comments at the end of THIS THREAD (http://www.exriders.com/vbb/showthread.php?s=&threadid=237664).

wow that was helpful. thanks. ur right, i never really understood how to read a plug and i thought i did!!! well i was wrong. thanks again. boy gpracer, ur like a walking engine dictionary:D

[dork]

DJ's are rated on bore diameter. keihin's are rated by their hole diameter, so a 155 has a 1.55mm hole, mikuni's are rated by area, or flow, of the hole. i don't know about dynojets. also he wouldn't want to go leaner, look at the A/F graph. and reading plugs on an air cooled is very deceptive. i've found you need 2 hard runs to get some color at the porcelin base, and you need to cut off the threads to see otherwise you're wasting your time.

[F-16Guy]

I think you're a little rich, too. I'm running a 160DJ main with my 11:1 416cc, and it still feels a tad rich. I can't imagine that a stock engine with just a full exhaust could flow the same amount of air. I think the Dyno Jet instructions are way off. You would have to have internal work along with a pipe and filter before even considering their "Stage 2" jetting.

[GPracer2500]

Whatever size jet is being used is somewhat irrelevent. The air/fuel data chart is what matters. The bike is NOT rich. Just look at the chart....

[F-16Guy]

Don't you have to insert the analyzer probe directly into the exhaust stream? How can that be done with a disk diffusion type silencer? If it's drawing in outside air as well as exhaust, wouldn't that cause the reading to indicate on the lean side? I'm not saying that I know for sure, I'm just trying to figure out a possible answer. If I were to put a 160 main, Dyno Jet or Kehin, in my wife's bike, it probably wouldn't run worth a crap (a 152 Kehin was too much). I just don't see a full exhaust and the airbox lid removed being able to accomodate that much of an increase in fuel. There must be an answer, because it doesn't sound right. Maybe I'm just dumb?:confused:

[GPracer2500]

Interesting question about the probe....I wonder how that's done on diffuser disk systems? There's gotta be a way...

BTW, I certainly don't think you're dumb and appreciate that you're trying to make sense of somthing that doesn't seem to fit your experience. I have to agree that everything I've ever seen indicates that Dynojet's jet numbers are smaller than an equivalent Keihin. I mean, a 400EX DJ kit comes with a DJ134 - DJ170. I've never used DJs so I couldn't really say what's what.

[krt400ex]

all i've ever heard is that the dj jets r bigger by comparison. like a 160 K is smaller than a 160 DJ. so that is what i based my opinion on. the discs r removable, so that would be how u would do a probe reading. u just remove the discs

[F-16Guy]

I would have to say that Dyno Jets run richer than Kehin (smaller DJ number equivalent to larger Kehin number). After installing my WB E-Series and K&N filter with lid removed, I rejetted with the DJ kit and ended up with a 146 (or 148, I can't remember exactly, but it was one of the two). Stock Kehin is a 148, so I'm almost positive that they aren't exactly the same. You also have to consider the different needle that comes with the kit; that could drastically change almost everything but WOT. Maybe he's right on the money, but it just sounds fat to me.:confused:

[F-16Guy]

Originally posted by krt400ex
... the discs r removable, so that would be how u would do a probe reading. u just remove the discs
The problem with that is that you would totally negate the benefits of the pipe. Forcing the exhaust through the disks is how that style of pipe makes power. By eliminating the first disk that blocks the end of the pipe, you are ruining the effects of the pipe and most likely losing power.

[krt400ex]

Originally posted by F-16Guy
The problem with that is that you would totally negate the benefits of the pipe. Forcing the exhaust through the disks is how that style of pipe makes power. By eliminating the first disk that blocks the end of the pipe, you are ruining the effects of the pipe and most likely losing power.


u lose bottom and gain top by removing the discs. more backpressure equals more torque, less backpressure equals less torque and more top. trust me, i tried it with my 300ex. that's not the point though. the point is to be able to stick a probe in the end of the pipe to see if ur air/fuel ratio is right. by removing thee discs u won't be changing the ratio so u will still get an accurate reading. it just makes it easier to get a reading when u remove the discs. see what i'm saying???

[F-16Guy]

Originally posted by krt400ex
u lose bottom and gain top by removing the discs. more backpressure equals more torque, less backpressure equals less torque and more top. trust me, i tried it with my 300ex. that's not the point though. the point is to be able to stick a probe in the end of the pipe to see if ur air/fuel ratio is right. by removing thee discs u won't be changing the ratio so u will still get an accurate reading. it just makes it easier to get a reading when u remove the discs. see what i'm saying???
Adding disks and subtracting disks alters flow, yet still allows the exhaust to function correctly. Totally opening the endcap and eliminating the disks defeats the purpose of the pipe and drastically alters the performance in the useable range. If you did that when you put it on the dyno, what good would it do?? The idea is to measure the performance of the quad configured as you would normally ride it. That's what I'm trying to explain. Could you dyno it with the endcap removed? Yes. Would the information mean anything? No. To me, the only accurate way to analyze the exhaust gasses would be to have some kind of a boot that fits around the silencer in front of the disks and funnels all of the exhaust out reward past the end of the silencer. You could then insert the probe in the boot near the disks and measure pure exhaust gasses.

[cals400ex]

well whether that is rich or lean, i do not know. what i do know is that my bike is quite a bit faster with a little smaller jet in place. also, with a higher compression piston there is a good chance you will need a smaller mainjet. i always run mine a little lean from what the air fuel meters say because that is how it runs the best....

[cals400ex]

and by that i am not saying this is what everyone else needs to do. i do not go much leaner but do go a little leaner. maybe a jet size or two.

[PismoLocal]

I remember when I first joined this site there was a pipe shootout that ATV riders did between HMF, Yoshi, Sparks, and white brothers full systems. In the end if I remember correctly the WB pro-meg system came in 2nd right behind the sparks there was less than a 1hp difference between the two systems I'll see if i can find it.

[roostonu]

Mobile Dyno,on the air/fuel chart you posted you said the spike was caused by the accelerator pump not keeping up.Is there a way to compinsate for that?When I was running the D.J. needle thats about the range it would fall on its face.

[krt400ex]

Originally posted by roostonu
Mobile Dyno,on the air/fuel chart you posted you said the spike was caused by the accelerator pump not keeping up.Is there a way to compinsate for that?When I was running the D.J. needle thats about the range it would fall on its face.


ya, buy a boyessen pump if they make them for the 400ex.

[NY06400EX]

The only true way to measure an accurate A/F reading is getting the sniffer as close as possible to where the header meets the engine. Racing teams often drill holes called "bung holes" (no joke lol) into the headers. They are threaded so that you can quickly thread an "exhaust stop" into place when you are done taking readings. Obviously you can just as easily unthread them to put the sniffer back in when tuning for different environments/mods. This practice is used in sportbikes, dirtbikes etc. A tad more costly though when you initially have a shop set this up before a dyno tune.