Right.. I'm just trying to give you all the information I have on the subject. Which is probably more than you need..LOL I know your thinking about the Chinese knock off..

Also, the megabomb+ PowerCore4 ( My full FMF system.) saw an increase in upper RPM power over the stock header + DG-R, on the Dyno. Once again, perhaps information that is not important to your situation...
If you ever perform the MCM mod, that DG-O + stock header will help to create a huge
torque rise right off idle - yanking into a wheelie in first gear.. see my video on my signature line...

 

I have around 200 miles now decided to check plug color
looks fine
will check in a few more months just to make sure

brown starting to show up hard to see the photo made it lighter





and the stock exhaust/jetting before doing the mods but over 6000 miles on this one

 

Plug readings like that mean absolutely nothing.

 

im going to have to disagree
ive been tuning small engines for years now, and never seized one yet going off of plug readings like this

I know about "plug chops" and they dont work maybe because of the fuels we use now
nothing shows up on them, and thats even cutting them apart to look for the smoke ring

this plug tells quite a bit

too rich even after a short ride the entire plug would be black and sooty
rich right now would have hints of dark or black on the white area
black on the metal electrode

to lean the white would be white
and the electrode would be silver, or crusty white

ive found all the small bikes ive rejetted takes about a weeks worth of riding to get the color to soak in once the preliminary jetting was figured out
Usually go rich, check for soot and back down if needed
then ride for a week and check color

this is what I was expecting to see if it was jetted right

and I bet in a few more months it will start to look like the old plug


ive had people not jet and there old 3000 mile plug shows up clean and white
as the lean burns away any old coloring
or too rich is the opposite

when I was doing 95% freeway riding this weekend im glad to see some brown showing
if it was too lean, at that high rpm for 40 min at a time then I would expect it to still be white

now the bikes I do may not be precision jetted using an air fuel gauge or whatever
but I dont have to obsess about perfect jetting
just as long as it runs fine, and has gains over what it was before im happy

 

According to my Dyno charts - Your bike should only see AFRs dip to the middle 13's:1 ...
Still lean for max power but the best we can do with the DJ kit... I'm getting larger DJ jets to dyno test..

 

I did order this header last week and it finally came in today
NEW S/S BOMB Exhaust head header Pipe 2006-13 KAWASAKI KLX250S KLX250SF KLX250

I tried my best to get info from the seller on the pipe size, but I think the seller is in china and they said the warehouse this pipe was in was located in florida so they couldnt get me any measurements

All I was concerned about was if it didnt fit I didnt want to get stuck with shipping costs back

They made it seem like if it was perfect condition they would cover the shipping back so when it showed up I did a video opening the box, showing any damage which was none
then showing if it would slip over the stock exhaust, since thats what its made for

It does fit on the stock muffler and my new dg muffler and both fit slightly loose
From measuring the inside diameter and installing a new gasket then would make it too small for the pipe to slip in


I wasnt sure if its supposed to be that loose, ive deal with slip on exhausts before and they were always snug

So after checking it was the same bends as the stock header, and having to drill out the flange holes a hair larger I decided to put slots in it like the stock has
and use that clamp to tighten it all down

I also wanted to put the gasket inside just to prevent any leaks but I had to strip the layers of the gasket away along with cutting it to make the diameter smaller

here is a photo of the slots I made sure the slots were shorter then the pipe sliding in
Not to cause gasses to blow past the slots if that happens



Once fired up I could not hear or feel any air leaks, since it was super cold I was able to wrap my hand around the pipe and up front no leaks either

Since it was a cold startup it was really quiet, alot quieter then using the stock header and the dg muffler
Since ive been riding the bike daily since installing the new exhaust I actually hated the loud noise it made right when starting

So that little clone bomb does keep the noise levels down
But we will have to wait until the bike is super cold again to do my db test, I tried after riding it hard for a while and its a touch louder using my meter, plus the idle may be higher then when its cold too
Still falls under the max noise level at 2000 rpm but then who knows how accurate my ipad is compared to the official tool

So I will wait to get an official noise test maybe later today


Riding it you can also tell its quieter , and on the freeway
before it would blast my ears a little, now its a touch quieter

Thats about all I can say now, I want to get more rides with it


The whole reason I was doing this exhaust was to get more power and still keep it quiet which I have achieved so far

 

Got cold startup video made

so here are my readings

Keep in mind im just trying to be under the sound levels that I see online looks like every state has the same rules

from 20 inches away at a 45 degree angle at idle you want to be 92db or less
and for a v twin or smaller at 2000 rpm you want 96 db or less

Since my bike idles almost at 2000 rpm, just under it im trying to see if I fall under the 96 db or less

also my tests are done in a sealed garage which may bounce more sound then outside
but since my original stock test was done this way I want to keep everything the same


So all stock I had readings of
85-87 db max out at 94
not sure if they go off of a max level, or a running changing level


Just aftermarket muffler
at idle 88-90 3 db more then stock
100db max 6db more then stock

And the whole exhaust setup, muffler and header
at idle 88-90 3 db more then stock
peak level was at 95 1 db more then stock

so it looks like the bomb header really does help with sound
not sure about performance

 

Hey Mike, I believe you are the only member to get and use that Chinese header successfully..

Please start a new thread with a descriptive subject line, E.G. " Ebay Chinese PowerBomb install and Use" ... So that, for ever more, anyone can search for it and find your thread. Transfer these last few posts to it and keep the info coming..

You da man..

 

OH, BTW, that is about the best looking KLX I've ever seen !!!

 

someone let me borrow there air fuel ratio gauge setup they made to fit into bike exhausts

From a little searching I guess we want to be under 14.7:1?

and that 13 is rich, and 15 or higher is lean

Anyways I did a quick test tonight, will do more thorough one tomorrow
I want to mark the twist grip so I can check 1/4 1/2 3/4 and full

all I did tonight was 1/4 and full
both read 13.2

I was more concerned about full throttle anyways so guess if its rich its better then lean

I was told this setup was tested on a truck and read perfect

so probably should read the same on my exhaust


This was at idle long enough where my cooling fan came on
wanted to make sure everything was hot enough before using incase that matters




the setup







I may try it on my other bikes one I have is fuel injected but I had big bored it, larger injector and fuel controller was added
so really curious how that one reads