The OP did two things at once: the MCM and carb setup. Read the thread. I've stated twice now that the intake and exhaust mods were done well before the MCM and carb changes. And the MCM and carb changes go hand-in-hand. But go ahead and be an internet tough guy if it makes you feel good.

 

Its your experience, how anyone can question that is beyond me.. power to you and your adventures in modding the klx!

 

Lighten up Francis

fzrcraig said the same thing. Don't cry over it, its just the internet

 

Fantastic buy at $0. Infinitely good deal.

 

There's an interesting question. Has anybody done the MCM to a bone stock bike? No jetting changes, snorkel still in, peashooter exhaust. Since the MCM seems to like additional fueling over stock timing, will it make the factory lean jetting worse (unrideable)? Maybe keeping the snorkel in keeps the jetting close enough.

So what other free mods could one do to a bone stock KLX for $0? Drill out the cover over the pilot screw and adjust. Remove/disable the KACR. Drill the starter jet, if you have the proper drill bit already (unlikely). Air injection delete?

 

Someone has done the MCM, to a 100% stock bike, as a 1st mod - me.

Results are incredible.. In fact, the increased power sparked my fascination/hobby with experimenting on the KLX to tease out mo-powah..

I have no idea what the fueling curve would look like. Back then, I was not dyno testing. But the bike performed perfectly..


It makes sense that MCM+dead stock bike shows significant gains. With the stock induction system and exhaust, the intake/exhaust velocities are kept high - this aids in TRQ production from off idle to some point in the mid/upper mid range.

 

No performance benefit per se with the removal or disable of the KACR other than easier starting, nor with the removal of the pollution equipment. Drilling of the starter jet will help starting, but again not overall performance either. Drilling the air box lid, yanking the snorkel or removing the lid will only make the bike run leaner if not jetted. Adjusting the idle mix will help when just off idle, but little else.

So for zero money the MCM is pretty much it. But as KLXter says it does a fair amount to the performance.

 

I wasn't implying "performance" mods only, just anything that makes the bike more user friendly/better in general. Easier starting, less decel popping, etc. are still desirable traits to most riders.

Didn't mean to thread jack, so I'll stop my tangent there.

 

Then delete the compression release, drill the starter jet, it will start better. The pollution stuff really doesn't affect anything performance-wise. Don't screw with the air box/lid/snorkel until you are ready to jet. The bike is so lean to start.

When you have jetting right some decel popping is normal. The best tuned motorcycles do it, as do cars. If you fatten up the pilot circuit to cut it down you are making the idle mix overly rich. If you want to end it, set your idle high or slightly crack the throttle to eliminate it. Personally I don't get shook up about it because I know why it happens and that there is nothing bad about it. Done the research, plus tens of thousands of miles on two big singles that did it with no ill effects. Do the research, find the true authoritative answers. You will arrive at the same conclusion I did, whether you try to eliminate it or not.

Here was one source at All Things Moto

Another source at Mikuni, yes the carb maker

 

Sorry KLX678, I ain't takin the bait this time..