The International CBX Owners Association

New member with a question that’s probably silly. I’ve just taken over a 1982 from my Dad. Been going through some basic maintenance and figuring out what needs replaced or repaired and what doesn’t. The bike will fire on starting fluid, so I feel confident that if the carbs would feed a good mixture then we would be in business. I was hoping to fill the bowls with fresh fuel and some Seafoam to try to dissolve any deposits and also drain the bowls to see what comes out.

Now I’ve seen several discussions on here about the value of regularly draining the carbs when the bike is going to sit for any period of time, and it’s a five minute job and everyone should do it… and I’m absolutely baffled at how to attempt to drain #3 and #4. I can get a long screwdriver onto the drain plugs for 2 and 5, but I’ve no idea how to access the middle carbs. I’m sure there is something simple I’m missing but would appreciate any guidance.

1,2 and 3 are accessed from the left side, 4, 5 and 6 from the right side.

Thanks for the quick reply! I guess my initial post wasn’t specific enough. When I read about people draining carbs as basic maintenance for storage, I assume that meant with the carbs on the bike. Obviously if they are removed you could simply remove the bowls. But I was hoping to learn how to drain 3 and 4 while still on the bike

There is no trick beyond having a screwdriver long enough to reach the bowl drains assuming you have a normal set of CBX carbs.

avstaub3 wrote: ↑

Sat Oct 14, 2023 6:16 pm

Thanks for the quick reply! I guess my initial post wasn’t specific enough. When I read about people draining carbs as basic maintenance for storage, I assume that meant with the carbs on the bike. Obviously if they are removed you could simply remove the bowls. But I was hoping to learn how to drain 3 and 4 while still on the bike

The pictures are just for a reference, you don’t need to remove anything yet but I see a complete cleaning in your future! LOL

Jeff Bennetts wrote: ↑

Sat Oct 14, 2023 7:00 pm

avstaub3 wrote: ↑

Sat Oct 14, 2023 6:16 pm

Thanks for the quick reply! I guess my initial post wasn’t specific enough. When I read about people draining carbs as basic maintenance for storage, I assume that meant with the carbs on the bike. Obviously if they are removed you could simply remove the bowls. But I was hoping to learn how to drain 3 and 4 while still on the bike

The pictures are just for a reference, you don’t need to remove anything yet but I see a complete cleaning in your future! LOL

I agree. I think these units will need to come off. I don’t think I’m getting any fuel into #1 and the fact that this engine won’t hit a lick suggests that there is likely a number of jets that are plugged and need to be cleaned. Im still struggling with getting a clear understanding about how the carbs are supposed to be drained when on the bike. If I shine a flashlight into the carb rack, I don’t see any path to reach the #3 and #4 drain screws. No matter how long a driver I use, there doesn’t appear to be a path to put a tool on the slot. Is it the case that the carbs are hydraulically linked and you can just drain the three pack by loosening the screw on the outside carb? That would encourage me because at least I would know that if I get these things clean then I could maintain them moving forward.

They are not linked. You need to drain individually. Have you removed the fairing lowers? That makes it easier. I will take a picture tomorrow if you are still having trouble.

Your carbs very likely need full disassembly to replace all the orings. That is a job best sent out unless you have some experience at it.

After you get it sorted, I highly suggest that you run it dry at the end of the day's ride.
In that way, you're good for a day, a month or longer.
If there isn't any fuel in the carbs, clogging can't happen.

Parking a hot CBX with the carbs full of fuel, the heat rises and just cooks off whatever fuel is in there.

Even before the introduction of ethanol, gas eventually turns into varnish.

One guy's perspective and experience: First, do pull the carbs and dismantle for a complete cleaning AND replace the orings being certain to use viton material orings; second, do drain the carbs if the bike is going to sit more than a day. Yes, all you need is a long enough thin screwdriver to get to #3 and #4. I've been doing this for 30+ years and never had an issue with carbs.
P.S. If you want to get everything as very dry as possible, do this: run the engine dry, pumping the throttle while doing so to empty the accel pump. THEN, drain whatever remains in the bowl bottoms. Because the internal tubes do not get to the very bottom of the carbs, there will be some small amount to drain. Maybe just drippings -- but, some. A bit extreme. BUT, .......

This angle with a long screwdriver will access
#3 and #4 carb drain screw.

Ok that’s the ticket. For some reason my brain was only thinking about approach angles from behind. I’ve been able to get to all of them successfully. Thanks a bunch.

Larry Zimmer wrote: ↑

Sun Oct 15, 2023 11:39 am

One guy's perspective and experience: First, do pull the carbs and dismantle for a complete cleaning AND replace the orings being certain to use viton material orings; second, do drain the carbs if the bike is going to sit more than a day. Yes, all you need is a long enough thin screwdriver to get to #3 and #4. I've been doing this for 30+ years and never had an issue with carbs.
P.S. If you want to get everything as very dry as possible, do this: run the engine dry, pumping the throttle while doing so to empty the accel pump. THEN, drain whatever remains in the bowl bottoms. Because the internal tubes do not get to the very bottom of the carbs, there will be some small amount to drain. Maybe just drippings -- but, some. A bit extreme. BUT, .......

Agreed.