Installation Instructions
The single best thing you can do to your KLX 300 Dual Sport or Supermoto. For only $349.95
Here you can see 3 dyno graphs. The red line is a stock bike in 4th gear. The yellow one ( middle one ) is a stock bike with just the secondary throttle plate removed. Yes, I know, big difference where it's needed. It's about 30 minutes of work for you and it's free. The orange line ( top line ) is just with ECU reprogramming. This is with a stock pipe and air box and the secondary throttle valve out. You have to admit, it's a hell of an improvement. It's a 4-6 hp improvement through the mid range, and this fluffy bike really needs it. With big gains throughout, and snappy throttle response, it's the absolute best modification you can make to your stock bike, after the secondary throttle valve is removed.
Price of the ECU reprogram? Only $349.95
In this chart, now the bottom line is the stock bike with the secondary throttle valve out. The orange line in the middle, is the bike with the ECU reprogram added, and the top line, is with the ECU, a modified stock exhaust and air box. Again, what a gain. The air box mod and stock exhaust mod are basically free. You drill some holes in the cover and sides of the box, and cut some slits in the side of the pipe with a hacksaw or cut off wheel. And this extra air flow in and out of the engine, as you can see, gives you another 1.5 hp over most of the RPM range.
Here, you can see the big gain you can make for a small $349.95 price. Over 6 hp in the middle and big power from idle to wide open. And it's hardly any louder than stock. You don't have to twist the throttle as much, to have the power needed to go down the highway at 60 mph, so the mileage increases for most people. This chart is the stock bike you bought on the bottom, run in 4th gear, and the gain you get for $349.95 plus the opening up of the stock exhaust pipe and air box lid.
There is no single mod or set of mods (pipes, intakes, tuners and dongles) that comes close to this gain. If there was, we'd sell it.
I think at this point, it's a good time to lay it on the line as far as truth goes. The middle line, in the graph above, is what most of you internet chat influenced riders may be running. And don't take take a drop of this as insulting. We were sent free pipes from Deklivic and Yoshimura, so as to get us to sell the pipes. The middle ( red ) line, is the secondary throttle valve out, the stupidly loud deklevic pipe, the KDX 220 snorkel, and 02 sensor delete and the ejk programmer on the best settings we could get. And it got its ass purely kicked, for half the money or less, by a quiet bike for $349.95. Which is the top line with the ECU reprogram and the holes drilled in the airbag and the cuts in the stock pipe.
What do we do, to the ECU, to get a bike to run this good.
1. We fix the ignition timing. This is key, and obviously this power and throttle response adder, can't be done by just adding fuel. The 2020-24 KLX 300 S and SM models, are the equivalent of soft little puppy turds, when it comes to power producing ignition timing.
We add timing starting at 2200 RPM. We taper it off up to maximum torque. The we retard it a bit until redline. This make the bike much more responsive and also pull harder up to 6000 rpm. The backing of timing from 7500 - 10, 000 rpm, helps with power on top. This is one reason why the ECU reprogram is so much better than just a fuel adding device.
2. We change the Intake Air Pressure ( IAP ) parameters. It clearly states in the service manual, that the IAP is one of the main inputs the ECU uses at lower rpm's, to determine fuel needs. This is something we have access to, while inside the ECU tables. A nice performance gain was found here, and this is something no ( dongle ) or piggyback programmer can compete with.
3. And then, obviously, we optimize fueling. There is a fuel map for each gear, 1-6. Each one was optimized for great fueling, while utilizing the stock 02 sensor.
And finally, here you can see what happens when you use a straight through muffler. Look at the bottom graph though as well, which is the air / fuel ratio. All of these runs have the secondary throttle valve out
So the yellow line on the bottom, is the deklevic muffler and the kdx 220 snorkel in the air box lid, along with the best piggyback programmer settings we could get. You can see fueling is a bit rich at the top end, but not bad.
The middle orange line, is the new ECU, the holes in the air box lid with stock snorkel and cuts in the stock muffler. You can see fueling is pretty perfect throughout.
The red line is the deklevic muffler, the kdx 220 snorkel and the ECU only. It is best overall in power, but loud and no spark arrestor. The thing is, most will notice that fuel around 4-6000 rpm, is pretty lean. With this being said, a smart person, would try unplugging the 02 sensor to see if that added more fuel here and possibly running better. Or adding some fuel with the piggyback programmer, they probably already have, and seeing what that does.
I just don't like the loud pipes. BUT, many people do. If I wanted to use one, and was after all the power I could get, well then it would be pretty obvious, that between the ECU and a piggyback and probably the right 02 delete dongle, you could make a KLX that few could compete with. And for around $900
