bogging

[crzyd247]

hello i have a 84 atc250r that a guy gave me didnt know much about it so first not sure what to run gas oil mixture at but ran it a lil and seems to start ok idle ok i start going and then hit it and kinda bogs then slowing clears up and takes off so i took carb apart was clean so cleaned it real good again and back to together and still doing same so i looked at pug its wet and black is to much oil in gas mixture or airscrew jacked up

[hairytriker]

Surely the 250 is also a 4 stroke? Correct me if I'm wrong but I thought all ATC's were four stroke... :confused:

[mohadib]

Um no. Maybe the venturi has failedl lol.

[hairytriker]

Forgive my noobness, I've just looked it up & the 250r is indeed a smoker. Bang goes my theory then...

Is the exhaust pipe the right one & not clogged up with spooge, and if it's a non-original 'zorst then maybe it just needs jetting to suit... Same goes for airbox/filter

[crzyd247]

so i check pipe its clean airfilter clean new plug gas mixture is good and carb is clean idles and good mid throttle boggs then clears up faster you go any ideis main jet maybe should i lower it a cuople or what

[hairytriker]

Sounds like a bit of a carburation flatspot, perhaps the needle or atomiser have worn at the mid-throttle point through extended use in that range. If your plug chop readings are good then I'd try replacing these with the same as what came out & go from there.

[crzyd247]

can you order these parts i know the needle but not sure what you talking about with the atomiser

[freestylejunki3]

if its bogging on mid throttle try raising the needle clip up (lower the needle) to lean out the mid range.

[crzyd247]

stock needle clip position is in the middle i raise it one so lowered the needle down but took it out seemed to be almost the same

[freestylejunki3]

do a plug chop to verify that the top end is ok before messing with the main jet. If the plug chop comes out ok then leave both jets alone and just mess with the needle position. Try putting it at the top instead. If you see any difference then maybe you should get a thinner??? needle to lean it out and that way you can keep the clip in the middle position

[Xfile]

I had an 84 r with that problem once. The little spring clip that holds the needle to the bottom of the slide was missing: removed by the previous owner and never re-installed. When you backed off the throttle the needle would push up into the slide instead of going down into the needle jet.....this caused the machine to run extremely rich unless you where wide open (The only time the needle was in it's proper position)......just an idea.

[crzyd247]

ok whats best way to do a plug chop do i need a fresh plug i seen people write diff ways on doing it whats your way of it shutting it down with throttle wide open or hold it wide open then let off and and shut it down