Thread: Power loss, sounding louder and not ideling after mud event

Recently rode a very wet and muddy 2.5 hour hare and hounds. On the last 30 minutes of the race my KTM 200 2 stroke suddenly got louder and there was a noticeable power loss, so much so it took a long time to get up the last hill.

There was a bit of mud in the airbox where water had seeped through the airfilter. I cleaned the carb (small about of mud found) and replaced the spark plug but with no luck. I have also check to see if there are any holes or broken seals on the exhaust system. Next on the list to try is the reed valve, but wanted to ask on here first just in case someone may know of another problem it could be.

the packing in the silencer may have let go

it wasnt the h and h at stonehave by any chance was it?

Na Fullabrook in north devon.

Would the packing in the silencer make such a huge power decrease? TBH I have never replaced the packing so it wouldn't hurt if I done it anyway, however it would either have to be cut open and somehow re-sealed, or buy new.

Reeds were fine. I stripped the carb again and made sure everything was propper there. I also tried replacing the silencer but still no difference in performance. I guess the next thing to try is the powervalves .. hmmm.

Had the same on mine after i drowned it at a event, It turned out to be the piston rings as the fine mud had made it's way into the cyclinder. Piston and rings needed changing and a cyclinder replate was on the cards to.

Might be worth a check as this is what mine sounded like, the rings were half as thick as the new one's.
Half a hour to pop the head of and have a look.

Worth checking that the expansion chamber hasn't got pushed over against the cylinder if you've dropped it in the mud. This had two effects when I did it on a 125. Firstly it makes the expansion chamber ring with vibration from the cylinder and secondly it pulled the pipe out from the head and it wouldn't seat properly losing loads of power. Simple check and beats stripping the head & cylinder off.

Thanks. I've had the pipe off and checked it over. All seems fine and when running there doesn't seem to be any blowing but I guess the only real way to be sure is to get hold of another pipe to try.