Topic: Hey Fellas

[NickC]

Just picked up a 1975 CB550K for $300. Needs to be cleaned/tuned up a little bit. I don't have a problem turning wrenches, in fact, I had it tore down some the night I got it home. I did have a few questions on it though.
The PO said he replaced the head gasket then parked it. I got it running fairly easily, but had to dial in the choke to get it idling good. Should I pull the carbs and start with some base adjustments, or try tuning them on the bike? It was running EXTREMELY rich, carb overflow drain tubes were dripping pretty good. Even when i parked it overnight, it left a decent size fuel puddle underneath it.
I drained the oil, smelled strong of fuel. Would this be a cause of running too rich?
I've read that these aren't that good in the braking aspect, does the double disc conversion help any?
Thanks,
Nick

[kghost]

Carbs overflowing enough will put gas in the engine without it running which then makes its way to the oil.

Diminishing its lubricating properties as you may imagine.

Sounds like you'd be better off pulling the carbs and cleaning them before attempting adjustment.

[NickC]

Next question,
How the heck do I get the carbs off, I can't even get the friggin plastic air intake assembly out of the way1

[kghost]

I don't have a 550.

On the 350/400 I push the large airbox gasket into the plastic airbox. (after removing the clamp)

Usually gives me enough room to slide the plastic out.

But like I said...don't have a 550

[burmashave]

Welcome.

I don't have any help for you on the airbox as I have a 750 and am running with velocity stacks.

[mystic_1]

Welcome.  Sounds like your floats are stuck, and the carbs are overfilling with gas.  Remove and clean them as suggested above.  As far as removing the carbs, I've never done a 550 but I know that on some models you need to remove the battery tray and possibly also the rear fender in order to give yourself enough room to move the airbox back a bit.  This gives your clearance to get the carbs out.

cheers
mystic_1

[TwoTired]

550 carb removal has been posted on the forum several times.
Disconnect fuel hose before removing tank. (Get in the habit of turning off the fuel petcock when ever the engine isn't running.)
The most overlooked key, is to remove the clamps on the air box couplers completely,
Remove the two bolts that hold the filter box in place (so you can move the air box/couplers bakc the quarter inch, you'll need it.)
disconnect move out of the way the top engine breather hose.
Diconnect drain tubes on the bottom
Disconnect throttle cables
Loosen the clamps nearest the carbs on the forward rubber couplers.
The rear rubber couplers, hopefully, are still are soft enough that you can push off the left side of each so that they ares now behind the carbs.

Now get ready to wrestle some.

Pull the carbs backwards just enough to clear the front couplers and push them to the left until the hang on the rear couplers.

Once again push/manipulate the rear couplers so they are behind the carb inlets.
Pull the carbs backwards just enough to clear the front couplers and push them to the left until the hang on the rear couplers.
Once again push/manipulate the rear couplers so they are behind the carb inlets.
Keep this up until the carbs have been marched off to the left and off the bike.

The removal process is hard on the rear couplers so anything you can do the minimize stress and tearing on those is worth while.  You can get replacements from DSS in the UK, though...along with a new airbox.
The harder those rear couplers get with age, the harder the removal process gets.

Check your gas tank for rust.  Clean carbs wont stay that way if you feed them nasty fuel.

Before taking the carbs off...
I would drain a carb, like #1, into a clean pan and check for debris in the fuel.  The bottom of each carb bowl has a big drain screw.  You can even remove the float bowl while the carbs are still on the bike and have a look inside.  Then you determine if it is too clean to pull the carbs or if they really must come out.

Gas in the oil from overflowing carbs is a very bad thing.  Check the carb bowl drain hoses for blockage, they are supposed to prevent overflow from getting to the cylinders.

These are fun bikes when running well.  You should enjoy it!

Cheers,

[NickC]

Thanks for the help guys, I managed to wrestle the carbs out tonight, going to open them up tommorow afternoon and take a peek inside. Adjusted the valves, some were WAY out of wack.
So far, it seems like $300 wasn't too bad of a deal afterall!

[mystic_1]

Do change that oil.  Now that it has gasoline mixed in, it's no longer a lubricant!   

$300 and a lot of determination can take you far on one of these machines.

best luck with the carbs

mystic_1

[pdxPope]

Do exactly whatever Two Tired tells you to do. No more, no less and you will have yourself one happy motorcycle.

As far as the braking is concerned 'aren't that good' is kind of relative. Compared to a modern motorcycle- pretty lousy. Compared to other bikes of the era- amazing. One of the selling points of the SOHC 4's were that they were the first bike to come w/ a disc brake standard.
A dual front setup will certainly improve things, but don't expect to do any stoppies.

The 550 is a great little bike. Light, quick, nimble. There are a couple of guys here who ride theirs so well, they can compete on the street w/ modern sportbikes.

By the way, $300 for a runner is a steal!

Welcome aboard.

-JP