Hey guys,

Not too long ago, I`ve posted about an annoying whistle coming from the exhaust. Well, the time has finally come and I am buying a Powercore 4. My 12yo boy is coming back from Mass next month and he`s bringing it to me.

I`m thinking on getting an EJK unit, but I am not sure if I really need it with the new pipe. Do I?

Plz, gimme some thoughts.

Thanks.

 

I had the EJK on my 250. It does help feed more gas and enrichen the mixture. If you add a free flow air filter, like a Uni and remove your airbox lid, or snorkle, you will be running very lean. By adding pipe and filter, you will feel an improvement using EJK.

I upgraded my 250 to 300 and bought another reprogrammed EJK for the 300, as the 50cc extra demands more fuel.

I have a spare EJK for the 250 wich I am willing to sell at 150USD. PM if you are interested and I will check postage prices to Brazil.

 

Thank you for the reply, Graham. And the offer, as well. But my concern is customs. If I buy from the US, I have people to bring it to me and there's no risk of paying import taxes, etc. $150 is excellent, but it can turn into $300 very easy if it goes thru customs.

I am just replacing the pipe. Everything else will stay as is. Do I still need the EJK unit?

 

The EFI can handle small changes, like altitude, atmospheric pressure etc.
I fitted a tail pipe before EJK controler and noticed some popping on deceleration, indicating lean mixture. However that being said, a pipe alone should not contribute to a leaner mixture. To get real performance you need to get more air intake, as well as more out from exhaust, and then you need to flow more fuel to compensate.

To sum it up the pipe will sound good and you may feel a bit more throttle responce, but you will not be getting giant second gear wheelies all of a sudden.

 

Cool. I just want to replace a faulty stock pipe. Really not looking for a performance increase.

 

I forgot to mention, if you look closely at your stock muffler, you will notice that it has a Lambda probe, or CO2 sensor bolted into the pipe leading into the muffler. The new muffler you are getting will not have the bung attached to the small piece of pipe leading into the FMF muffler. The CO2 sensor is important as it sends info to your EFI controller. The only pipe purpose made for the KLX 250 EFI ( that I know of ) is the Leo Vince X3, with the bung attached.

So easy fix will be to take the pipe and have a hole drilled and the bung welded in, so you can screw in the probe.

 

Yeah, I am aware of that. Does the EJK for the KLX come with a sensor bypass?

 

Yes, without the bypass, the piggyback controller will not be able to overide the original mapping.

 

Hmmm...then if I get an EJK, I won´t have to worry about the sensor on the pipe, right?

 

Correct.
I see on your signature you are running modded cams?
Marcelino mod? How is that working out? Did you do the full mod or just intake. ACR?