Topic: First CB 550

[78whiteorbs]

Hi guys, I just bought my first cb 550 ,it is a 75 model. The guy I bought it from was a really easy going nice honest guy. He had the bike and another bike extra I got as a parts bike for free. I paid $700 for everything and he threw in like 5 helmets 2 crashbars, a set of engine guards, a zip lock bag full of emblems, 2 different windsheilds(small and large)  and luggage rack. What a deal huh! The bike had been totally gone through and had a ton of new stuff. From shocks to coils and points  , alotta ebay shopping  he did and then parked it two years ago in his garage and didn't touch it since for some reason. It only has 5,o56 miles on it . has new paint  and new tires.

When I showed up to check it out he said that the battery was dead from it sitting for 2 years without being tended to. So we jumped it off and it fired right up. There was a small drip from carb four and cylinder 2 header was not hot so it was running on three cylinders I accessed. I drove it down the street and the battery was so dead it would not even take a charge so it died. He had to help me push it back to the trailer were we loaded it and I happily paid him!

Upon getting it home I bought a new battery and checked the gas. Installed the battery and it fired right up! Sounded great. number two header was still not getting hot and wasn't firing. I pulled the plug wire off and checked for spark and it was surely sparking nice and bright so spark was confirmed. I took it for a test drive around the block and it backfired a little . I but it to bed and went to check on her the next day and Fired it up again , the bike has stock exaust and sounds great. Here is where I am now, When I have the carbs on full choke it idles fine and would idle  until it ran outta gas. If I open the choke the  RPM's rev up and it is obviously getting to much something. All and all I think that it shouldn't be to hard to fix with some help from alll you guys out there. I had a 74 CB 750 before this and it was very similar engine. One thing I have observed taking the parts bike apart is that the stock airbox is a mofo to remove so the carbs gotta be a pain to remove and install, also it seems  not to be enough room for pods to be ran. I intend to set it up cafe style with the clubman bars. Well that's about it . I have a whole nother parts bike which ironically the gastank is spotless inside and on the running one there is some rust in the tank (whick I intend on coating)

so whatche guys think?

[78whiteorbs]

forgot to mention to one strange thing is it is kinda hard to push with my feet. My 750 was way easy but somewhere there is some resistance. Brakes are good and not stuck or anything, I was thinking wheel bearings or maybe the chain needs lubing or something. The chain on the parts bike was actually rusted to the sprocket so it laid rubber when we loaded and unloaded it. The chain has since been smacked around a bit and it rolls now !

[78whiteorbs]

here we are

[78whiteorbs]

some  more 

[swan]

Welcome to the forum. CB550 are great bikes, easy to maintain and run and ride great.

Clean your carbs, they are dirty from sitting for so long. Fresh gas is a must.

E-bay all the extra crap you bought to offset your purchase price and you should have a fun ride.

[78whiteorbs]

in daylight it looks blue.

[78whiteorbs]

Thanks Swan those were just my intentions.  Look at this poor young bike someone left to die in the elements. Only had 14k on the odometer! I was thinking someone could bore out the block and use it perhaps once more. It is seized. I jumped on the kickstart and the weathered fork boot shattered into a buncha piece but the engine did not budge! Funny thing as much rust as exists on the outside the tank is spotless inside!  Ironically the Better looking /running bike has some rust in the tank. HA never judge a book by its cover, I guess.

[78whiteorbs]

Isn't it possible to remove the low speed jet needles and clean them without removing the carbs. I am really intimidated by the crappy position of the airbox . With my old 74 cb750 it was quite easy to remove the carbs . With these I was thinking clean what I can without removing them and run some high octane and seafoam ,clean the tank and petcock and put an inline filter. Let it run with some carb cleaner and it would be alot less a hassle. Not lazy or anything but it is idling nice and I don't wanna screw that up . Also I'd have to have them re -synced which I would like to avoid till I got some money in for selling extra parts and whatnot.

[jreich]

Very nice find there...

Here is some good advice for removing the carbs: http://forums.sohc4.net/index.php?topic=5704.msg48277#msg48277

It's a bit tricky at first, but once you get it, you got it!

If you want to run pods, they will fit, but you will need to get the 35mm version, so they fit: http://www.crc2onlinecatalog.com/Index_Main_Frame.htm

I accidentally bought the 39mm version for one of my 550's, and had to cut them all off, use a heat gun to remove the excess from the metal plate, and then jb-weld the new shorter filter and the now clean mounting plate back together....long story short--get 35's


Oh, and change that oil and filter!

cheers
JD

[jreich]

Isn't it possible to remove the low speed jet needles and clean them without removing the carbs. I am really intimidated by the crappy position of the airbox . With my old 74 cb750 it was quite easy to remove the carbs . With these I was thinking clean what I can without removing them and run some high octane and seafoam ,clean the tank and petcock and put an inline filter. Let it run with some carb cleaner and it would be alot less a hassle. Not lazy or anything but it is idling nice and I don't wanna screw that up . Also I'd have to have them re -synced which I would like to avoid till I got some money in for selling extra parts and whatnot.

Take my advice, as my mind has been where yours is right now, and taking a shortcut with the carbs will only take you the long road around.
Take the carbs off and clean them right...then bench sync them...you will find good advice on how to do all of this here. It is not as difficult as you think, and I bet that the bike will idle even smoother than it does now.

[78whiteorbs]

Yeah, I know I know.     I cleaned my cb750 and it ran much much nicer afterwards. Just wasn't as tight with the breather box. Gonna bite the bullet though. Wish me luck. Wondering this too, I mentioned that the bike idled great at 1000RPM's with the choke on full (all the way up) when I brung the choke downwards the rpms revved up like crazy. Could I have the thumb screw set to high so that the choke on  is actually feeding the proper amount of mixture ? What would make a bikes RPM's shoot though the roof when the choke is disengaged and idle great when it is fully choked? Baffled.I know this has gotta be a no brainer but....

[bryanj]

The tickover screw on the carb rack (big thumbscrew) is wound too far in, with engine HOT back it off till you get about 1,000-1200 ticover revs comming down with choke on is just running too rich, If No 2 aint firing first FIT NEW PLUGS and probably Plug caps.

If its been apart the carbs will need synching properly but you can bench sync with them off to get a starting point probably good idea to remove and totaly strip/clean the jets and pathways

[78whiteorbs]

Thanks for the advice ,will do today. I actually have some extra NGK plug caps from my old bike.

[78whiteorbs]

Well, I found some gold today hiding under the seat. The guy I got it from had no seat key so I took the hinges off and dissasembled the lock  and drilled it out so I can turn it with any key now. The gold I found was a swiss army knife (one of the huge ones!) and the original owners manual . Also a set of titanium bolts for something on the engine ,package was still sealed and has a business card of the  ebay guy that sold it . I am wondering what these go to ?

Changed plugs with new NGK DEA7 (or something like that with the seven , I forgot but they are the right ones I googled it.)  When I pulled the old plugs they where black with carbon and the  number two cylinder which wasn't firing was blakc but  not as much as other and was wet with gas. I fired that puppy up backed the thumb screw adjuster out alot and now it runs with out choke at 1000 RPM's !!!!     I also assessed that the low speed jet must be clogged on the non firing cylinder because when you rev  up the throttle to around 3000 RPM you can hear an increase power and reving it for a while around 3000 rpm got the #2 header hot. So I am gonna unscrew the low speed jet tomorrow and clean it out. Also heard about Yamaha carb cleaner which you drain all the gas from the bowl and fuel lines and and feed it though the carb like it were gas but let it marinate after a few starts with the engine shut off switch at off position so it will not start on you. Anyone ever use this?  Also found out why It "pushed "funny when just moving  it around by foot. The chain was hella slack way outta specs so I went about screwing in the two end bolts to tighten the chain. I think I might need a new one because the last mark is reached. Any how this is when I seen it  , the one nut that holds the rear wheel axle on was "finger lose" !!! Man oh man . and I drove this around the block! Thank god it didn't come off. I no to look for such now in the future though!

all in all it was a productive day for me ! I am very excited about this bike . I am painting the emblems with model paint now to bring them back to %100.