Bike Runs rich

[MQTGSR]

My best friend just got a hell of a deal and bought this 72 CB550r I believe it is.
Bike is in perfect shape, and everything works, it runs and the like, but has one problem.

The bike runs too rich. According to the seller, the carbs were re-built, but may not be 100% stock parts that were used in the re-build. Is this a case of simply adjusting the carbs to lean the mix out, or is something else screwed up like a float, float pin?? Would it be worth it to try to fix these carbs or get new ones. Also, the bike fouls plugs kinda quickly as a result of it running rich. What is going to take to get my buddy rolling? I am new to bikes, but fairly knowledgeable on engines. This is my first bike I have worked on, but I reckon I can figure it out.

Please any help or input is greatly appreciated.

[h22lude]

does he know how to use the choke?

[MQTGSR]

Yes, that does not fix the problem, it just runs rich, I am going to try to play with the carbs today see if we can't lean it out a bit. BTW its a CB500t not R. Sorry.

[h22lude]

You could just take it to a local shop and get the carbs rejetted.

[MQTGSR]

That was already done. I am prob. going to take it apart today or tomorrow and I can possibly see what is causeing it.

[ReCK1]

If a shop already worked on it and it didn't fix the problem I don't see what you can do yourself, other than re-building the carb.

[MQTGSR]

I found out the float is stuck. The place that rebuilt it used the wrong one. Dumbasses.

[Sirfallsalot243]

Replace the float with the correct one, and set it to proper spec. A stuck or improperly set float is one of the most common carburator problems. Carbs are very simple, so while youve got it apart, I would completely disassemble it. Thoroughly clean the float needle valve, the main jet, the pilot jet, and set the needle to the proper position for your altitude. I dont know how to set the needle based on altitude, so I usually end up doing the "try it, and see how shitty it runs" method. Then pick the best, and go with that.

Keep in mind that after youre done, you should do a WOT test (take it down the road at WOT and pull the plug immediately afterward). This will give a good indication on how well the bike is jetted, especially the main jet. If you had a low RPM bog, id suspect the pilot.

[MQTGSR]

Yup, got another buddy of mine who knows bikes well to help me out. We're gonna take the carbs apart, clean em, make sure nothing sticks, and that it is adjusted right. Change the filters and plugs, and boom, were set!