I have 300 miles on my RX200HP. All was well, and suddenly my scoot
started lurching during steady driving, suddenly decelerating by 1-15
mph. WIthin a few minutes, it got to the point where I had no
acceleration. I basically putter along at WOT. If I let off the
throttle, it idles OK, but I go to WOT, and I peak at about 12 mph.

I also noticed that I have some blackish smoke coming out of the
exhaust when I open up the throttle.

Any ideas? I fear I may have blown a ring. How can I get repairs or
parts? I\'m not sure if I have any warranty hope--the bike is only
three months old.
thanks,
John

Check your air cleaner.
It may have gotten too much oil blow up there from the crankcase vent hose and if it did, your paper filter will be saturated and not allow enough air flow and will do just what you describe.

To fix, put in a new filter, reroute the oil breather hose out of the airbox.

You also may have to take the carb diaphrahm on the side of the carb apart and clean out the oil that gets in there as well.

It can screw up things as well.

There is quite a bit of oil in my air filter. I\'ll try that. I need to find a replacement filter somewhere...

poked a couple of pinholes in the filter, which seems to help--it ran a bit better, but still undriveable.
I ordered a new air filter and will try it out and report back.

Anyone have advice on the best way to get access to remove the carb and get access to the diaghram?