Thanks, I'll try the idle. I'm running 89 octane pure gas now so I'll tinker with it and see.

 

I have been interested in this mod, unfortunately none of the pictures were on this thread. But I am curious if the sprockets are bolted on the cams is it necessary to remove the cams? Why not just rotate the sprockets on the cam shaft and bolt them in the new positions? Additionally why bother unfastening anything other than the cam chain tensioner, once the chain is loose couldn't you just rotate the intact cam and sprocket to the new position reinstall the tensioner? As per the compression release, some have suggested that it could be simply removed, sounds like it's a press fit and it could possibly be driven out while the cam is still mounted?

 

unfortunately, I couldn’t just rotate the sprockets.
I followed the mcm mod pretty much to the T. It was a little hairy, but it worked out great!!

 

I think the problem with 'just rotating the sprockets' is that the chain may not have enough slack to jump over the teeth, which would be required.
The compression release, can just be wired in non use position as I remember it, but if you have the cams out, you could do it.
I didn't do the MCM mod or the comp release, I went 350/slide carb route and happy with that.

 

I watched a Youtube video, where that is exactly what the guy did, However he only changed the exhaust timing, Another concern is why Kawasaki didn't do this from the start? Why would the manufacturer leave horsepower and torque on the table, seems it would have given them an edge on the competition. Curious as to why the European and Australians would be different? As one other person suggested that the ACR was a left over from when the KLX was kickstart, and that the e-start models had no issue starting without it. Again why would a manufactured add unnecessary parts?

 

Kawa couldn't - MCM is not emissions friendly.
KACR eases the cranking load on the starter - but we have found that the starter is quite happy to turn over the engine with the KACR disabled.
If the KACR is a concern, take the time to reposition it for operability with the MCM - I did this and it works great.

Anyone watching YouTube vids on the MCM will be led astray - last I checked, there are no accurate vids on MCM - only vids that could cause harm to your engine.

 

Thanks for the response. I just picked up this 2019 KLX250, 1894 miles. One of the questions is that if I perform the MCM, will the oxy sensor change the fuel settings and is this even necessary? I have already discarded the airbox lid, not particularly bothered by the intake growl, did notice an improvement, some say 1.5 hp?, but again been wondering about the fueling. Down the road I may also be looking at altering the exhaust as well, I formerly had a 2015 WR250F, that I GYTed, and it turned into more of a race bike than I wished, since I have bough an XT250, nice trail bike but found it wanting in the power dept. I was surprised the stock KLX really didn't show much of a power improvement, what with liquid cooling, 4 valve head and the FI. The KLX differs from the WR in that the cam drive and tensioner are located on the right side opposite the stator. Curious about this design.

 

Your 2019 is going to have fuel injection. Correct?
I’m not sure about the mcm on FI. I followed klxter’s protocol on the mod and jets. Maybe someone else will pipe in with FI ideas.

 

As said, Kawasaki had to meet emissions standards around the world. The other reason is a bit contrary to what is written about the MCM, but considering circumstances in context it makes sense. I read an article on cam lobe separation angles (LSA) in Hot Rod magazine. The MCM narrows the LSA, increasing valve overlap, which will actually take away from the off idle area while boosting mid-range and up, but according to everyone doing the MCM, it boosts the "low end". Now consider low end with the KLX is around 3000 rpm or so, with a small block Chevy it is around 600 rpm, so if the boost works in mid range in the car it would equate to what small motorcycle riders would view as "low end". Wide LSA, which reduces valve overlap, will increase low end - car low end, while taking away on top. Sounds crazy, but that's the facts Jack. click here for the article

The thing is we seldom ride under 3500 rpm other than really puttering about. So we see mid range in that 3000 rpm area. We also aren't concerned with manifold vacuum or a lumpy idle at 600 rpm. So what we see and feel is the boost that is happening well above idle, in actual mid range from around 3000 rpm up. Makes it a modification for what is essentially free power, just some mechanical effort.

As for the compression release, my 09 250 would start in single digit temperatures (°F, well below freezing) no problem, with the compression release fixed disengaged. Disengagement can be done by taking off the spring. I mechanically fixed the shoes in disengaged position, but spring off does the same effect. Best is to just press it out. Neither the Yamaha WR250R nor the Honda CRF 250 uses a compression release, just the Kawasaki and per a lot of us, no difference noted. So no compression release for me.

And why the cam drive on the right? Because they designed it that way on the original KLX250 in 1994. The drive is more accessible than the left hand drive on my KLX650. On it you have to pull the stator and covers to get to the chains, on the 250 you pull the clutch cover and I think only the crankshaft primary gear need be pulled. I've never done it so I don't know if more need be removed, but it sure looks easier. Performance advantage? Nope, none. But no disadvantage either. The Suzuki DRz400 has the cam drive on the right side, as probably others will too.

 

Assuming your exhaust system is stock, the need for a fueling tuner is not that great. Once the slipon or entire system is replaced, you must also get and use a fueling tuner to add the huge increase in fueling that will be required.