It went very well ..until I dropped one of the EX cam gear bolts as I started to screw it into the cam flange

I'd told myself to watch out for exactly that before I started the mod, but I got cocky and sure enough-down it went into then bowels of Hades. I was wishing I still had my cheap but useful Globemaster skinny extension wand magnet after I finally spotted that short cam sprocket bolt's threads waaay down there-probably atop the lower gear that's on the crank. I was resigned to having to pull the clutch cover to get that bolt..

Then I remembered I had some neodymium magnets in assorted sizes, so I stuck the smallest diameter one I had into the end of some small ID float bowl breather hose. It's a strong magnet yet weak enough that it wouldn't pull itself out of the hose by simple contact with steel pieces on the way down. I did test it on some steel here and there before actually dropping it into the cam chain cavity.

I slid about a foot of that hose onto a ss kabob skewer and lowered it in. On the second try I heard that beautiful "click" and pulled it all out to see that cam gear bolt happily hanging on to the magnet !


Whew !


The bike started up good and idled fine. It's raining hard so it looks like a/f and performance testing will have to wait until this weekend. Since my timed testing with the CVK was probably inaccurate (quicker than normal?) due to the air box boot being askew at the carb, I'll put the 36mm back on since I know its performance precisely, and dial that in/test it post-MCM before fiddling with the 34CVK.

That will tell me right away if the MCM has been a gain for me.

 

Haha, good show!! I had a cr250 that all of the sudden stop shifting, split the case and found a 1/4 length screw, chewed to **** jamming up the shift drum. The PO had the bottom end just rebuilt at the shop(receipts) I guess highly skilled bike techs can screw up.
Looking forward to hearing your impressions and testing having done MCM,
Cheers Richard

 

If your going to test from 17kph, be prepared for a power wheelie in 1st gear..

Well crap, so the CVK test is no good.. Disrupted airflow at the boot would produce unknown effects..

The steeper TRQ curve may allow a more aggressive setting/timing on the accelerator pump. I don't expect the AFR curve to change, but that will be very interesting data to see too..

 

Marcelino felt jetting changes would be the key to making it work to full potential, but if I don't need to be fiddling with the carb-all the better. The 36mm is in place and if there's no rain later today I can check a/f and then performance once I know the jetting is okay.


The poorly installed CVK boot may have uncovered a little power+ option for people not wanting to invest in the larger carb though.

The HP difference between the CVK and 36mm will show up while testing them ala MCM. I'll even leave the boot off one try with the CVK to see if the ET changes vs with it on.

 

I lucked out big time yesterday

 

I'd imagine it would be pretty hard to have that bolt disappear without noticing.

 

I figured that would happen with me too if I did the cams in situ.

I broke the bolts loose while in the head, then pulled the cams and relocated the sprockets on the bench. I started the bolts in again, with blue LocTite, then installed them in the head and torqued the bolts. Then I retimed them per the specs published... after I think four goof ups getting the chain on the right teeth of the sprockets!

Reading Bobby Knight's book "The Power of Negative Thinking" kind of reinforces that thought process. If you can get it, do so and read it. Very entertaining during monsoon season. It's Bobby Knight! Not much more need be said.

 

Went out for some a/f tests today. WOT a/f ratio was in the 12s but power was down - the bike's power felt like it was only seeing half throttle ..

I won't even bother checking its ET in a sprint. I'll just go back to stock cam timing.

I double checked my cam gear placement yesterday and I did the mod correctly; it's just not doing anything for me at this level.

 

Cam timing is back to stock, no test ride-it's raining hard; but I started it up and it sounds like its old self again. - As it should

Starts easier as well with the ACR spring back in place. The battery wasn't digging the lack of compression release.

Ah well...now what? Maybe a short anti-reversion spigot in the header using the round exhaust gasket as its base.

 

I can't understand the MCM causing your bike to feel like it was only getting 1/2 throttle - that is a huge, and scary, power loss .. Perhaps the MCM, in fact, doesn't work on older KLX's