125-200cc Cr165 missing on top

My 08 cr165 ran like a scalded cat all season. On my last ride the bike wouldn't come on to the pipe near as hard and was missing at the top of the revs. It ran fine on the bottom and mid and started just like it always had. I changed out the plug and had the same results. Running a lectron and the wb pipe. The plug wasn't fouled and looked nicely brown although perhaps a little on the lean side. I richened up the pj but it made no difference. The guy behind me said the bike smelled richer. I checked for air leaks around the carb boot with starting fluid and it seems all good. Open to suggestions on where to go with this.

Thanks in advance
K

Check your ground at the coil. Make sure it is tight, clean, and not cracked. Also when the power jet is too rich it will miss like that but I don't know why it would change.

Gotta check all the basics first: fuel flow/petcock screen; ^ ground, plug wire/cap; compression! filter; muffler. Be interested in what you find out.

...after Steve's excellent checklist, the next level would be things like the power valve, reeds, loose jet, flywheel, rag (or mouse) in the airbox, etc.

compression check for sure... lower compression will cause richer running and less pull when on the pipe.

Ditto on the reeds- they flap a lot and are overlooked.

I have found that bad reeds will usually make it hard to start and run strange at low rpm but the high the revs, the better it runs. Since we don't have penny's in Canada anymore my 2 cents are now free. Lol

Thanks for the suggestions. Well, I finally found a bit of time to put in to this. A kitchen renovation and life seemed to have got in the way. I found a connector on the coil that wasn't tight, that isn't to say it was loose but the connector could move on the bolt. Reeds check out good. Unfortunately it seems winter has arrived here so I now have the bike in the basement to do winter maintenance and repairs. I'll keep you posted on what I find.

Thanks again

Reading this reminded me of this http://www.odsc.on.ca/.xenforo/index.php?threads/black-smoke-and-bog-past-1-4-throttle.15592/

tl;dr
I'll sum up 4 pages: he fixed his sparkplug wire problem and still thinks it was a carb problem

Interesting read. Its amazing how you can get locked in to a train of thought and lose sight of the big picture, I'm sure we've all done it at some time. The above thread reminds us to be methodical and check ALL the basics first.
Thank you for posting.

The difference between a professional mechanic and a backyard mechanic is troubleshooting. I called it on the first page

I posted it because I thought Chef might remember it, and he may have a similar problem. He's on that forum too.