Bogging at mid range

My sons 65 had been getting worse and worse towards the end of the season just seemed to be loosing power. I have the entire thing torn down right now and do not have a compression problem with the piston and cylinder. I cleaned and rebuilt the carb and put on new reeds (although I dont think the old ones were bad) I was tapped out when i thought since i have this torn down this far i should repack the silencer.

OMG what i found was a disgusting mess of goo!

When i removed the filiment the baffle holes were filled with carbon, less then half of them were cleared.

It is clean now but I was wondering if that was the issue I could have been having?

the pipe does make a big difference in power delivery, but I cant say if this plugged up core would do much for power. The soaked pascking and clogged holes would make it louder tho. For the small KTM questions you should go to KTM talk where they have several sections dedicated to the small bikes.

Try it with the newly packed silencer. Clogged up can't be good.

"My job as a mechanic is pretty simple. All I have to do is restore a car back to how it left the factory. The factory did the hard part turning raw metal into a motor." - Long time auto mechanic

When in doubt, restore to factory specs, then try to improve on it.

Yeah i posted out on KTM talk but they were Super slow to respond! I know i can get answers on here faster.

I am putting everything back to stock then working from there. That was my intensions all along!!

Thanks guys!

2 big clues

1) clogged exhaust. way too much spooge

2) bogging at mid-range.

Cure

Jetting.

Sounds like the needle is too lean and the main jet is too rich. Drop two sizes on the main jet and put the needle's clip one position lower (richen the needle.... put the clip down lower on the shaft of the needle)

Welcome to the world of backyard mechanics. Save some $$$ and experiment. :applause:

yea it sounds like jetting. whenever a bike bogs it is most likely jetting that is to be blaimed.

jetting...the only thing wrong with this theory is he said it kept getting worse n worse. He didnt say he changed the jets or anything else that would now suddenly make the jetting be off to make it do that... I would say worn out top end and maybe clogged pipe. Jetting may be off, but it ran fine at first so that doesnt sound like the main problem to me.

jetting...the only thing wrong with this theory is he said it kept getting worse n worse. He didnt say he changed the jets or anything else that would now suddenly make the jetting be off to make it do that... I would say worn out top end and maybe clogged pipe. Jetting may be off, but it ran fine at first so that doesnt sound like the main problem to me.

Yes you are right as the season went on it has got worse. that is why i was looking as the silencer was the issue.

I just did the top end and it all speced out good.

Motor is still off the frame and all and i am going to put the bike together this week.

Let you know how it goes

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