Assuming you simply pulled the spring off the KACR, or removed the KACR, it is not possible for anything about, or related to, a properly executed MCM to have caused engine damage or accelerated engine damage.

It is curious what line of reasoning would implicate the MCM for engine damage ?

 

@klxster, I'd venture to say it was the thing we saw at the bike shop when I worked there years ago. If something quit working, didn't work right or broke the owner would always blame it on who ever did what ever last. Like the time when a rider had the shop do the valve adjustment. He had some brake issues shortly there after and blamed it on the shop, because they worked on the bike last. Yeah, that makes sense... never touched the brakes...

 

While the cam mod is not going to hurt anything Lugging the motor down till it almost stalls all the time will beat the bearings out of it!!!!!!!

 

I agree, lugging too much is bad for any gas engine. The good usable power starts around 4500 rpm and goes up to max HP at 8600 rpm and will over-rev up to 10,000 without damage. Use it, the engine is built for it, not to work like a tractor.

 

What makes you think I go "Lugging the motor down till it almost stalls all the time"? In your attempt to paint me as somehow less than worth listening to you seem to have completely missed the point of my comment. Which, for those of you who were not paying attention, is that the cam mod creates more compression at lower rpms giving you more power for climbing hills on trails, not roads, that you would otherwise not be able to do.
False assumptions like that just make you look like the dumbass. You must be a "liberal". 🤮

 

That's not a statement I made !!!!!!
Have a great day

 

From reading your posts it sure sounded like you were running it at too low an rpm when you use the term "chugging along" and possibly so when you have to paddle to avoid stopping.

So both of us said to keep the rpm up. After around 22 years selling bikes I found a lot of riders tend to try to run too low an rpm, especially with smaller bikes. The smaller the bike the more a rider has to keep the rpm up. The KLX250, as I said, doesn't really pull down below 4000 rpm and keeping it up over 5000 is better.

As for compression, the MCM increases the valve overlap, the time when both the intake and exhaust valves are open, which would reduce compression at low rpm, which is in the area below around 2500 rpm. The increased valve overlap boosts the mid-range power, which so many riders confuse with being "lower range". Here is an article from Motor Trend, realize a gas engine is a gas engine whether it is a small block Chevy or a small single cylinder motorcycle engine, the way they work is the same.

Camshaft Shootout: Lobe-Separation Angle Tested and Explained... click here

Realize that the MCM makes the LSA narrower, increasing valve overlap, which is the time when some fuel mix will be pushed out, reducing compression at the really low rpm, but does better through the mid-range and up, just losing a bit at the top rpm. So if someone does the MCM and hints at running low rpm I'm going to tell them to let it rev, stay above 4000 rpm. If you do that then that's great. Your comments about chugging and having to paddle to avoid stalling make it seem like you needed to keep the revs up higher. But if traction is there in a hill climb eventually the bike will either drop down so low as to stall or it will spin. The MCM will have the engine stall out sooner, but at such low rpm that it won't make much difference between it and the original valve timing. That condition is noted in the article when a car has what is called "a lumpy idle" or " a lumpy cam".


As for your smart *** political comment, take that somewhere else. .