Kawasaki KLX300R running lean or rich after common modifications

[@pdevonport7266]

Fuel mixture and high compression is the reasons why European cars required higher octane fuel because the engine runs lean and hot so they have to prevent pre-ignition. It is regulation now that motor manufacturers have lean fuel settings whether it is chainsaws, lawnmowers and even large, diesel, tractors etc.

[@seethingsclearlyawaken3424]

This removal of the snorkel is quite similar to the DRZ400 3X3 Mod to the air-box. Of course, doing that one would need to change the jet and needle in the carb. Yours has no carb, but is injected. You may need to have it flashed. The sparky-plug doesn't really look lean to me. It looks about right. But yes, keeping the plug darker means keeping the engine' combustion chamber cooler is a good thing. I think you are safe. Especially if it doesn't feel lean either.

[@tieoneon1614]

Iv been telling people this for years on these KLX. They are not lean from the factory, too many people just repeat phrases they hear AND cant read a spark plug. Iv got 700 miles on my '24 with the snorkel out, more grunt and plug looks fine here.

[@bmotomo421]

The KLX comes in two states of tune. The 49 state tune. And the state of California tune. Mine was a 2021 California model. It definitely came from Kawasaki very lean. The combo of an EJK tuner, Uni air filter and cutting a larger hole in the air box made a noticeable power gain. That was with a modified stock exhaust. I later ran a complete exhaust system and readjusted the fuel tuner and it picked up another nice power gain. The stock air filter on the KLX is very restrictive. You can also free up some power by going to a high quality non O-ring chain. The klx300f is a way better bike than most people think it is. Do what you can to drop a little of its weight and it is a trail weapon.

[@italiansniper17]

@@bmotomo421interesting.. how did you find out yours was a California model?

[@bmotomo421]

@@italiansniper17 Well, for one, I bought it in California. Secondly, the California model has a big black box with a charcoal canister mounted behind the left side number plate.

[@discoveror9576]

Grey/black = rich ! White insulator = lean. A proper air:fuel mixture will result in a light-TAN colored center insulator (NOT grey/black, as you showed.)

[@fferris723]

My phone didn’t do much justice showing the plug. I’ve seen solid white plugs before indicating a lean mixture. This plug wasn’t bad at all. But it was black the way around before the mods. That I did not show but I did mention. Thank you for your feedback. Stay safe out their.

[@user-kt1bv3kx4f]

If the bike was already lean, increasing all the air flow in the airbox and out the exhaust without increasing the fuel is making it even more lean. Common sense

[@fferris723]

Well. As I said. People talk about the bikes running lean. I never said it was running lean. The plug was black when I checked it before adding all the mods. I should have been more clear. What I learned is this machine was not running lean before the mods. And after putting the mods on, she did lean out a little. But like I said, it was not a red alert situation. The bike was not running super lean with the mods. Anyway hope the video helped and that you for your feedback.

[@nickspatoulas2422]

Thank for the video! Great info! I have the same bike. Do you notice any decel pop? I hear some on straightways and was wondering if it’s normal.

[@fferris723]

Decel pop on this bike I’d normal. However if you remove the pair valve that will help with the decel pop. I have some other videos on my channel where I show how to delete it.

[@nickspatoulas2422]

Thanks!!!

[@lachlananderson4596]

has the bike got good power even with out the mods?

[@fferris723]

Yes had good power without the mods but a pipe is always fun to install and a blocked off air cleaner made no sense to me so the snorkel had to go. Bonus was an increase in power.