KLXster has done a ton of good work with that MCM mod and breathing. You can follow that recipe if you want and I am sure there are results to be had.

The 351 produces the bike I wanted to ride, for me. There is power everywhere, it's just a twist away.

The TM36 is an accelerator pump carb. When you crack the throttle on a regular carb it goes lean for a second before the jetting can keep up. The TM has an accelerator pump in it that richens it up for that second, so the carb response is instant, no waiting for the mix to return to optimal

Power isn't all about numbers, it has a quality too. For me, and I think for a lot of people, the 351/TM36-68 and some intake and exhausts are a very sure route to high-quality power. It's easy, a million people have done it, the results are known.

That said you are looking at several hundred dollars to do the whole basket of power performance. I am keeping my KLX, so that's not really a big deal to me. At this point,it's done. If money is an issue then I do I would not hesitate to go KLXster's route. Are you putting money away for retirement and maxed out your IRA contributions? You will get old one day.

I would also point out, if you're doing power mods without thinking of some suspension work you are not seeing the whole picture. I needed at least springs, and I decided on revalving both ends of the suspension, also not cheap.

Too many people buy a bike and endlessly mod it into something it never was intended to be. Think it all through and see what you want to spend overall on the bike.

I started with a $1,500 KLX, so I think that at $3000 more or less all in that it's a pretty good value.

 

I remember that when I was researching and Klxster knows his ****, but I thought I saw (or maybe it was Bill Blue himself) said that it wasn't wise. Again I might be wrong, when I have a minute I'll take a look around

 

The MCM mod and the BB do not play together. It's one or the other.

 

MCM on the 351:

The 351 fellas did a lot of "screwing around" before they finished the mod fully/correctly. Also they were "jacking around" with jetting at the same time.. So it's kinda hard to follow to the point where they actually tested the mod "fully done".. I'll list some of the pertinent posts that I found -
Post #149, #161, #163, #196.. Take a look yourselves and make up your own minds..

Know this: Jhoffy put in a 351 kit, MCM, and some other stuff, all at once. He rode it a little over 100 miles and loved it, then the engine "blew up" for some unknown reason.. Most of those Jhoffy posts have been removed.

MCM must be done without error - you screw around with this mod, doing it without fully understanding what your doing, and you'll likely be looking for another engine - or at least another top end..

 

Ok, Kansas-klx was still running stock bore when he did the MCM..

2veedubs put the intake cam back to stock settings when he put in the 351 kit. He left the exhaust cam MCM'd.. https://www.kawasakiforums.com/forum...s-37518/page2/ post #16.. He didn't say where his information came from..

#286,287,288 - Jimmy101 said he confirmed with Bill Blue that 351 valve clearances are the same as stock bore and that no issues should occur with the MCM..

 

So the issue of MCM+BB351 requires a lot of research in here. Many folks obviously did the mod incorrectly, jetted incorrectly, only did the intake cam, didn't reposition the ACR on the exhaust cam (hard hot starting issues)...etc etc..

If I had the 351 kit, I would research the crap outta the forum for any "hard data" concerning valve clearances, call Bill Blue for verification of valve clearances being same as stock bore, and I would certainly run the MCM - It's free power !

 

When I did the MCM I did exactly as intended and rejetted with very impessive results. I'll ask Bill about the valve clearances and decide from there. When I did do the MCM I removed the ACR with no side effects whatsoever. Going to the 351 can anyone see an issue not running the ACR?

 

No one knows about the long term health of the starter motor when running a 351 w/o the ACR. You'll be in uncharted waters.

 

Well I think I'll take my chances. I'll see if the starter motor sounds like it's labouring when starting. If not, it's staying off.

 

Also know that no one has a "before and after" dyno chart on a 351 showing the effects of the MCM. All you'll get is baseless opinions, as far as I can tell. Being a numbers/hard data guy, I hate that..