The International CBX Owners Association

Hi, I have a 1982 CBX with 10038 miles on it. It has been sitting under a tarp for many years. I have been doing a restore job on it and it is looking pretty nice but I am having some issues with the carbs. When I first attempted to start it I was able to get it going but it wasn't happy and turned the plugs black from an over rich condition. I pulled the carbs off cleaned them and put in all new jets, needles and seats and float gaskets. Now it starts on the choke pretty good and idles at 1000 ok but when I crack the throttle it hits about 2500 then stumbles and just lays flat. If you try and make it rev past that it just doesn't want to rev at all. If I pull the choke on about half way it seems better but still not quite right. I took a plug out and it wasn't all black. To me it feels lean but am not sure. Moving the idle mixture screws in or out from the 2.5 turns I had them at didn't seem to change much. Any ideas?

Many things - first, I hope you didn't throw away the stock Honda jets, needles and float valves. They are far better than any aftermarket you will buy. Clean them up and re-use them. Float valves may or may not seal - your aftermarket ones for sure will not. Replace any stock ones that leak with genuine Keihin ones. PJ Motorsports carries the real thing.

Otherwise, you need a COMPLETE rebuild. Carbs need separated and everything needs totally cleaned and tested. Your idle circuits are for sure still plugged and the accelerator pump likely does not work at all. Both accelerator pump and air cut-off diaphragms should be replaced. The connector O-rings need replaced with Viton items. If you still want to do it yourself, get Randakk's excellent rebuild kit.

Rebuilding these carbs takes about 10-12 hours of intense labor - IF you know what you are doing. If I were you, I'd pay an expert to do it. Mike Nixon is the best and is right near you. Best money you'll ever spend on your CBX. If you are a glutton for punishment, you'll have the carbs off at least 3 times and they still won't be right. The only way you are going to enjoy your CBX is if the carbs are right.

We'll help you along the way if you do tackle them again, but it will be torture.

Dave

Canuck, here is just one of the many aspects of carb cleaning. Idle jet removal.
viewtopic.php?f=20&t=6817

Words of wisdom from Dave.
Even if you attempt the next round of cleaning yourself, Mike Nixon should be looked into for advice.

The idle jets on the '82 carbs are threaded and easy to remove.

Dave

daves79x wrote:Many things - first, I hope you didn't throw away the stock Honda jets, needles and float valves. They are far better than any aftermarket you will buy. Clean them up and re-use them. Float valves may or may not seal - your aftermarket ones for sure will not. Replace any stock ones that leak with genuine Keihin ones. PJ Motorsports carries the real thing.

Otherwise, you need a COMPLETE rebuild. Carbs need separated and everything needs totally cleaned and tested. Your idle circuits are for sure still plugged and the accelerator pump likely does not work at all. Both accelerator pump and air cut-off diaphragms should be replaced. The connector O-rings need replaced with Viton items. If you still want to do it yourself, get Randakk's excellent rebuild kit.

Rebuilding these carbs takes about 10-12 hours of intense labor - IF you know what you are doing. If I were you, I'd pay an expert to do it. Mike Nixon is the best and is right near you. Best money you'll ever spend on your CBX. If you are a glutton for punishment, you'll have the carbs off at least 3 times and they still won't be right. The only way you are going to enjoy your CBX is if the carbs are right.

We'll help you along the way if you do tackle them again, but it will be torture.

Dave

If Mike Nixon is in the Mesa area I believe he has already been through these carbs but when I bought the bike it ran on 4 cylinders and blew black out the pipes. Now granted it did sit for several months after I bought it before I could get to it. I tried to contact the guy I bought the bike from but did not get a reply, I know he was sick so who knows. Initially I just took the carbs off and cleaned everything but when I put them back on it ran on all 6 but was still rich. I thought maybe I had been a little aggressive with the idle jets so I replaced them with #35's. The main jets that where in it where 105's so I put new 105's in, replaced the main jet needle and float valves and seats. Yes I do still have all the parts I took out. If indeed Nixon did these carbs a couple months before I bought the bike the other bits should be in decent condition still I would think. Does anyone have a contact number for Mike? I would definitely call him and ask his advice and see if he remembers the bike or previous owner. I would even go as far as taking them off again and letting him check up on me. I am no stranger to carbs as I have been a professional mechanic for 45+ years but these are for sure a special set up. Thanks.

Mike Nixon is not in Mesa, sorry. Mike is in Prescott and will be very helpful to you. He can be emailed at
carbrebuilder@gmail.com He also has a website www.motorcycleproject.com There is a tremendous
amount of information on his web site.
Best of luck,
Phil

Hi, I am in indeed in Prescott, AZ. Give me a shout. Thanks for the prop, Phil!