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Hey guys I have a 80' 525 and is idles at about 300-400 RPM very choppy now I have no idea about carbs I have a general idea of them. No I just wanted to know where is the idle screw so I can bring it back up and what should the idle be thanks. I will wait for summer to do this the car is under 8ft of snow.

You can read all the related FAQ's in the meanwhile, and Google search the subject here.

Pretty sure adjusting the idle with carbs will involve the same variables as with injection: starting with perfect timing, checking all vacuum related items, dip stick forming a tight seal, clean (brown) ground wires, happy fuel filters, pumps, regulator, then the carbs being clean and adjusted properly.

Well, that's what I have on my 74 Euro 525 (Twin Zenith carbs) and was VERY careful not to play around with them.
What I did was to order the repair kit for them. You can order them from Walloth (link under links here in First Five...) the Zenith carbs are also used on other BMW and some Daimlers. Make sure you identify the exact one as the Zenith have the INAT 35-40 or 32-40 (the exact year and month should tell though they are 99% the same).
Once you have the kit you MUST let an expert do the work. It can be done and once they are updated they work just fine.

Try the foll link:
Royze Carburetor Repair Kit

http://www.autopartswarehouse.com/sku/B ... Drivetrain

Be patient and do it, the difference will make it a whole new car...

I'm guessing you have a Solex 4A1 I think it is called, a single 4 barrel we never saw here. While I know the Zeniths pretty well, though I don't share Domingo's fondness for them, I know nothing about the Solex. Except I'm told it is very similiar to a Quadrajet. Very very similiar. So you might look for info on them.

People often dig further into carbs than necessary, and often plugged jets and passages are accessable without completely disassembling them, you can just pull a plug or a jet and squirt some carb cleaner spray in there and clean out the jet/passage. I got familiar with that when I had a Bav with the infamous Zeniths.

Long live the Zenith Carbs!

Mike's totally right about about some times making a mountain out of a mole hill!
I use to have a '67 911S with factory Webers that some times spit & coughed. All I had to do was blow the jets out with just my breath. Mean lungs, huh? That's why I quit smokin'. Ohh, I miss that car!!! Soft window Targa!
Another tip is to change the air filter more often, 'cause sometimes debris from the filter itself would be the culprit! Or so I was told.