1985 atc250es idle mixture screw - carb holder source?

[Otis0]

Hello all, I’ve have this 85 big red 250es , stock carburetor, and the idle mixture screw is covered by plug. I’ve seen the idle needle in part book and the manual has a spec to set it at. I drilled the plug to pull it out with a screw, as you do hidden idle screws. Is this how you all fix them? I’ve drilled deep as I dare 3-4 mm and haven’t got thru plug yet.
Also the carb holder is junk and I only see used holder, anyone making new ones ?

Thanks for any help, this machine is going to lots of it. Most of it is here and engine is not locked up, is about what can be said for it.
I have been reading here about the 85 act250es and this one has most of the common problems, clutch one way bearing slips when kicked, no spark / neutral wire, shifting is suspect but have only rocked the machine back and forth trying gears, wiring looks haphazard. I will get pic soon. I am grateful to all who have contributed to the wealth of information available here at 3WW.

[shortline10]

Only the newer replacement carburetors came with that brass plug .
We’re in south Florida are you ?
I have a power sports shop in Davie

[Otis0]

265360265359I must have it wrong then, this carb is QA 01A A W J. It has 85 style starter jet, I thought that was 85 oem . Well if this is replacement carb will I find a mix screw like I’m lookin for? I265358
Thank you short line, I am east of Ft. Myers out in the sticks along the river.

[shortline10]

Same carburetor just a newer factory replacement .
Drill out the plug , the mix screw is their , it might be the half moon style head instead of the std flatbread though .

[Otis0]

The plug is not pulling out because it is threaded. Probably not a plug like I thought, but is smooth topped tamper resistant mix screw. After pulling on it did not release “plug” I trimmed some aluminum from around it with dremel and then I could see my mistake, fine threads like mix screws have. I would have been better off cutting a slot across it had I known. It looked just like plug next to it.
On related topic, the intake carb holder is junk where is good place to get one?265388

[Otis0]

Next big thing is the carb holder, intake manifold, will a intake from a 300 ex bolt to the atc250es head? atc250 searches = squat but lots of 300 intakes . I’m ready to make a adapter to bolt to cyl. head with pattern for different intake bolt spread.

This carb holder has separated rubber from aluminum, for testing I’ve made the engine run by tying carb to head with wire to support weight.
Starts right up and I can blip the throttle and rev engine, I’ve had engines that stumble with slightest air leak. No air cleaner too. Must be rich.

Are the intakes out there and I’m too blind too see? Choke or enrichment plunger is missing and I need one. I’ve plugged choke for now.
—- I see now the 300ex is 4 valve, so that holder maybe not the one I want. —-
12/7 Have received used 250es intake from e seller, it is pretty hard but in one piece.