Topic: CB550 - New Brunswick, Canada

[Pawsoff]

Hello Everyone,
          My uncle (a motorcycle GOD/Guru) threw this bike together for me when I was 17. He said he was following up on an ad in the classifieds and that when he arrived this bike was nowhere near what was listed in the ad Kawi 1000 I believe lol. It apparently had been sitting by the beach unused for a few years, he gave it a kick.... it showed some signs of still having some life left and he took pity on it. He bought it for $50 and put it together with some parts he had at home (he always had at about 20 bikes around), with the intent to give it too me as he knew I was looking for one. I am from New Brunswick, Canada... and my uncle was living in the USA, Boston... I came and picked it up and drove it for about 1.5 seasons before storing it for quite some time. So lets say its been about 10 years since I have driven this bike. I have been "meaning" to get it up and running for a few years, but we all know how that turns out, you never get around to it. Well I am not getting younger and with the price of fuel nowadays, I have got the gumption to get it done.
I remember two specific issues:
1) the 2nd fuel bowl from the left? overflowed often.
2) the gas cap gasket turned to DUST!!! and gas occasionally spills over onto the tank.

          My brother (an automotive Jack of all with some motorcycle experience) was never able to get it running great.. good yes.. great no. We some new parts on it before it was stored: New Tubes, Tires, Rims (heavy duty), spokes (all in back, 1/2 in front), sprocket, chain, points?, muffler.... I think thats about it. I picked up some side covers (I only had one that was massively cracked) from a coworker a couple years back.
          There was an Old-Timer (90 years +) that used to have a bike shop and had a BUNCH of retro bike parts NEW that he had stored and was getting rid of, I picked up the rims and spokes there. The spokes were in no specific order  I had to go through a massive bin and match them by hand. I was only able to find 1/2 of the front ones so thats why only half 
           My uncle has become estranged and while I could get my brother to do this for me, I really would like to learn and do it on my own so to speak so I don't have to rely on others for repair, maintenance and upgrading of the bike.
           First off I figure I need a carb rebuild kit and a gas cap gasket, I would appreciate it if someone could tell me the part numbers and or a link where to purchase these parts. I would like to order them quickly as I figure it will take a week or two to get to me. I snapped off a few pictures of the bike (carbs are off at the moment) to show you what it looks like currently, the serial numbers for the frame, motor, carbs and some close ups of the gas cap and carbs (figure it will help identify them).
            My knowledge is limited and comes mostly from helping on automotive projects but I really look forward to searching even more through these posts and learning from your experience and projects, what some of you have done to your bikes is amazing.

Here are the pics:





















Thank you
Pawsoff

[TwoTired]

The gas cap gasket you can still get from Honda, pretty sure.

Your carbs are from a Cb500. Unless the jetting was addressed, you can expect the spark plugs to carbon up with soot, and the engine to run rather badly after that.

Your overflowing carb could be related to the rust in the gas tank.  If a particle blocks the float valve from closing, the carb over fills/over flows.  If it's been sutting 10 years, you can expect to rebuild/clean the carbs, after you take care of the gas tank corrosion and verify the fuel filter is still functional.  Get gasket sets from Honda, too.

They are good bikes and get 50MPG (40 minimum) when properly tuned and set up.

Cheers,

[Pawsoff]

TwoTired, thank you for the very quick reply. Do you know where the part number for the gas cap gasket can be found? My local guy has been promising to look in the microfich for a while but has not provided anything after my requests. Secondly, are you aware or do you know where I can find out what adjustments I need to make to the CB500 (627b) carbs, in order to make them compatable with the CB550 engine? I have a 4 into 1 exhaust and will probably go with pod filters.

[Pawsoff]

did a little bit more searching, my serial numbers (frame and engine) seem to fit with:

CB550K             1976       CB550E-1067334        CB550-1230001 

Which seems to make the bike a "1976 CB550 K2", with the exception of the CB500 carbs of course

[misterpunch]

online microfiches can be found on www.bikebandit.com.

I've never ordered from them, though I hear they're good, but they have a great site for looking up part numbers of OEM parts.  Pro-Cycle here in Halifax had no trouble ordering parts from Honda for me, but the less they make, the more you'll pay. 

[TwoTired]

TwoTired, thank you for the very quick reply. Do you know where the part number for the gas cap gasket can be found? My local guy has been promising to look in the microfich for a while but has not provided anything after my requests. Secondly, are you aware or do you know where I can find out what adjustments I need to make to the CB500 (627b) carbs, in order to make them compatable with the CB550 engine? I have a 4 into 1 exhaust and will probably go with pod filters.

I'd just call Honda and ask for a gas cap gasket for your bike.

Ugh, POD filters, too?  Why?  You must enjoy headaches! 

Well, I hope you have a test track, and the time to do about 20-30 test runs and plug chops.  Reading the spark plug deposits under various conditions is the only way I know to correctly tune carbs to engine configuration changes, short of paying for Dyno time to get a fuel use map at the various operating RPMs.

The easiest way to get your bike to run as new is to put it back to stock configuration.  Then it runs right and when you make changes, you can re-tune to make it right again.  Most people that modify bikes, first learn to repair stockers and then move on to "performance improvements" or customizing.  Kinda like learning to write short stories before writing an epic novel.

There may well be frustration in your future.  Getting it all dialed in correctly could take 40 or more hours of work, unless you are satisfied that it simply runs, rather than runs as it should.  I don't know what your expectations are.  But, you should know that repairing a bike and customizing a bike are not the same endeavor.  It can be done,  But, you'll have to commit to patience and perseverance to see it through to the end.

I don't think anyone here can tell you how to set up your carbs as they don't have your specific 4 into 1 exhaust, or the exact pods you choose AND your current carb set up.  I have some theories about how it might respond to changes.  But, we don't even know what your plug deposits look like now, or how it responds to throttle from idle, or how it behaves at midrange position, or if it can still make power at 95 MPH.  These are all things you will have to investigate, since you can no longer rely on Honda's engineers to set the adjustments for you.

You can do it if you want to.   Just make sure you want to beforehand or you won't likely meet your goals.  When you get it dialed in, it'll be a fun reliable bike.  If you lose patience, you'll just have something to curse at.

Cheers,

[Pawsoff]

all very good points TwoTired, where it is getting into the riding season for a while now, I think I want it up and running ASAP to get some seat time in, I will play with it more extensively in the off season. So I will be looking for a set of carbs for a CB550, is there any particular model (stamp) I should be looking for? One that is perhaps better in some way to the others?

[andy750]

Look in the FAQ - where should I buy my parts online section - plenty of vendors there - bikebandit is good, servicehonda, westernhills, davidsilverspares etc etc

Welcome!

cheers
Andy

[TwoTired]

all very good points TwoTired, where it is getting into the riding season for a while now, I think I want it up and running ASAP to get some seat time in, I will play with it more extensively in the off season. So I will be looking for a set of carbs for a CB550, is there any particular model (stamp) I should be looking for? One that is perhaps better in some way to the others?

Your bike came stock with 087A carb stamps (only the 76K model had these).  However, I'd not hesitate to try 022A stamped carbs, with original internals (74-75 K models).  Either of these carb selections, and the stock airbox, with perhaps a UNI NU-4055 filter will get you closest to stock with that 4 into 1 Mac header/muffler that your have.  As a guess, it may work well with that combo as is, or you may have to get a slightly larger main jet, or maybe add a double cone outlet restrictor to approximate the stock exhaust flow.  Can't know until you try it out, unfortunately.

I can already sense the "hurry up mode" with your comments.  This is not conducive to a successful outcome, IMO.  I can already hear the "I just want to ride it not work on it" coming to the fore.  Returning one of these neglected bikes to reliable operation requires just as much desire to work on it, as ride it.  AFTER, it is sorted out, then riding mode dominates, but not before.  You can't "bargain" with the bike.  It will run well when everything is sorted.  Proper restorative maintenance won't wait until it is convenient for you, regardless of how strong your desire for seat time is.  Are you willing to wait a month for parts to arrive and work to be completed?  If not, shop for a different running bike.  And, sell this one if you need a money subsidy.  (Just trying to set expectations to an achievable level here. I'd love it if you got the bike back into service.  But, such tasks are not for everybody.)

IMO, you are going to have to dig in to it and find out what it needs.
Getting it running may be the first step.   The 627B carbs have a habit if corroding the main jet holder towers, particularly #1.  Pretty much have no choice but to replace the carbs when that occurs.
Drop one of the outer carb bowls to access how grungy, or corroded they are.  It is possible to change the internal set up on those carbs to match any other set up on the 500/550 (Barring the PD style carbs).
However, because of the changes you have selected (pods for example), it may well be that NONE of the factory setups will suit your combination of parts.  In which case, you'll have to go through the same process, in tuning replacement carbs as the ones you have now (provided they aren't internally damaged).  The carb "bodies" are all the same for the cb500 and CB550K and F models, except the 1977-78 K models.

Have you applied wrench or screwdriver to the bike yet?  What do the spark plug tips look like?  You can post pictures of carb internals or plug tips if you need a second opinion.

Cheers,

[j-conn]

Welcome!
I have your bikes brother. same year same model!

[Pawsoff]

TwoTired, thanks for the replies, Yes I have had the carbs apart a few times in the past to clean them well. When I checked recently to see how they looked, I took of the fuel bowls and they looked very clean to my eye. I have a bunch of pics of the outside but no of the internals of the carb at the moment. I do not have a burning desire to go with pod filters, I can go with a stock air filter if it makes the tuning easier to work out. I will take another look at the carbs tomarrow and try to determine what internals are in it and what settings it is on currently.

[Pawsoff]

Connjob, hello to you as well, Glad to know I am not alone

Pawsoff

[TwoTired]

TwoTired, thanks for the replies, Yes I have had the carbs apart a few times in the past to clean them well. When I checked recently to see how they looked, I took of the fuel bowls and they looked very clean to my eye. I have a bunch of pics of the outside but no of the internals of the carb at the moment. I do not have a burning desire to with pod filters, I can go with a stock air filter if it makes the tuning easier to work out. I will take another look at the carbs tomarrow and try to determine what internals are in it and what settings it is on currently.

OK, here is what we need to know.   Verify the main jet is a #100, the slow jet should be #40, though I would prefer #38 for the 550.  The slide needles should have number 272304 and the clip should be in the 4th groove from the top.  The emulsion tubes behind the main jet must be clean, poke these out from the slide end, be gentle, that's the needle jet orifice you don't want to alter.  Set the float height to 22mm, And the idle air screws to 1 1/2 turn out from lightly seated.  Stock air box with a new paper filter or the Uni NU-4055.

I had a 75 Cb550 with these internal settings, the Uni filter and a Mac 4 into 1 that ran very well. But, it did have #38 slows vs, the #40 you likely have.  If we can't open the Idle air bleed screws enough to compensate, then you'll have buy #38 to put in there.

You will want to do a complete tune-up on the engine before final adjustment of the carbs.  New spark plugs (D7EA), points cleaned reshaped, gapped, and timed.  Tappets and cam chain tension adjust.  And, of course, a carb vacuum balance.  Were I you, I'd clean the tank of rust, or at least verify the fuel filter is clean and work as it should.

Who knows?  Maybe if you just clean out the carb jets, and verify the float height, it will run again? While you have it apart do check for hairline cracks in the stand pipe of the carb bowl, particularly the one you said overflowed frequently.

Cheers,

[mattcb350f]

Welcome from Ontario 

...In case you were wondering, here's a link to a list of all the Honda dealers in New Brunswick: http://www.honda.ca/HondaCA2006/dealers/default?L=E&Region=NB&express=false

 Cheers, Matt.

[Pawsoff]

ok, I have some work to do tomarrow
First I will have to search the site to see a diagram listing the proper names of the carb internals and how to remove / read them.
I have to get a new battery (any specific suggestions here or are they all really the same for bikes?).
See what parts I have laying around for this bike, its been awhile, still need to find my taillight and the airbox parts.

Pawsoff

[Pawsoff]

I took a more detailed look at the carbs this morning, mind you I am not completely sure what I am looking at
I believe I have found a couple of problems.
For the most part the carbs looked fairly clean inside although one bowl had a bit of gunk in it











When disassembling from the Fuel bowl side these were the parts I was able to remove and find markings for











Yes I did notice the rubber is in BAD shape on the #100 I listed, that was on my #2 carb that had overflow problems when the bike was going, guess what else was different about carb #2.....





One of these things is not like the other.....     Yes its a #38 tube instead of a #40

While I had the bowls off I looked at the overflow stacks, they looked fine, no cracks noticed, I blew air through em and plugged one end with a finger and had no leaks.

So to my knowledge (which is limited about bikes at the moment) the #40 is the emulsifier tube? #18 is the Needle & Seat? #100 is

From some brief searching I believe there is more to disassemble from the top end of the carb, to ascertain a clip position

Will repost in a bit.

Pawsoff

[Pawsoff]

Ok, I ripped apart the carbs to be able to get at the internals in the top, There must be an easier way to do that, will see if I can buy/order a manual today. Not a wasted effort as I had to take em apart to give em a good cleaning soon, will be fun getting em back together. I am always handy at taking stuff apart..... time to see if the reverse is true in this case

here is what I found

This is the slide




the number on this Pin? was 272304 and this is the clip position (#2 as its 2nd from the pointy end?)



There is a brass sleeve of some sort underneath the main jet, do I need to tap this out to find a number and or for cleaning?

Pawoff

[TwoTired]

Great.  You are making good progress!

For the most part the carbs looked fairly clean inside although one bowl had a bit of gunk in it

Ugh, that red stuff is some rust.  It needs water to form.  Gotta wonder where that came from, and stop it at it's source.  I'm not sure what that other residue is in the bottom of the bowl.  Suspect it's water corroding the bowl metal.  Does it clean up OK?

When disassembling from the Fuel bowl side these were the parts I was able to remove and find markings for
Yes I did notice the rubber is in BAD shape on the #100 I listed, that was on my #2 carb that had overflow problems when the bike was going, guess what else was different about carb #2.....
One of these things is not like the other.....     Yes its a #38 tube instead of a #40

you will need to buy new rubber.  I find the Honda kits the best to get.  However, maybe in your case, after market rebuild kits might be better as they will have new slow jets in the kit.  You will want to have all the jet be the same across the carb bank, or your will have to make one of the air adjust screws different from the rest to try and compensate.  I would prefer to simply use the Honda kits and buy 3 more #38 slows for the other carbs.  However, if the #18 seat and float needle tip is damaged, that can be a cause for carb overflowing.  How do those parts look, and more importantly can you check them for leaks when mated?

While I had the bowls off I looked at the overflow stacks, they looked fine, no cracks noticed, I blew air through em and plugged one end with a finger and had no leaks.
So to my knowledge (which is limited about bikes at the moment) the #40 is the emulsifier tube? #18 is the Needle & Seat? #100 is

Thats good news about no cracks.  The #100 is the main jet. The oring on that is important.  But, that won't make the carb overflow being bad.  The #40 is the slow jet, and it has it's own small emulsifier tube.  So, does the #100 main, but it is a separate part that you don't seem to have taken it out yet.

This is the slide

Looks ok.  The 2.5 is the diameter of the needle it accepts, the 103 is the same as all the other carbs on the 500/550.  I speculate the 103 number somehow relates to the cut-away dimensions.

the number on this Pin? was 272304 and this is the clip position (#2 as its 2nd from the pointy end?)

Nope, got that backwards.  The clip position is specified from the top of the needle which is non- pointy end.  Your pic shows it in the 4th position, which is a stock setting, I believe.  It's the right needle number, too.

There is a brass sleeve of some sort underneath the main jet, do I need to tap this out to find a number and or for cleaning?

That would be the main jet emulsion tube, mentioned earlier.  I haven't seen any numbers on them.  But, they do have small holes that should be verified clean.  I'd remove them for cleaning.  Be careful pushing them out, because the place where you push on them is also the slide needle jet orifice.  Wouldn't want to distort that.

There is a Honda shop manual in PDF to download from this site.  Page 57 shows your carbs.

Good work so far!

Cheers,

[Pawsoff]

Bleh, I forgot I had already downloaded that shop repair manual earlier on in the week, that would have saved me some frustration

I got em apart without taking off the cap (hex) nuts, they didn't want to loosen up and I didn't want to tweak anything, hopefully I didn't, the manual (of which I shall print off the carb section for now) will help me further disassemble the other 3 carbs. I picked up a hardwood dowel 1/8' this afternoon, 80 cents well spent I figure as that seems to be the recommended way to remove that brass sleeve under the main jet. I also picked up a gallon of varsol to clean up the carbs when totally disassembled and some 00 Steel wool (for outside parts only).

When I looked at the tank again yesterday, I did not see any rust inside that was obvious, there seems to be an Orange paint? overspray or something in there on the inside walls. Is there a in tank filter on this type of tank?

I was of the intention to get a carb rebuild kit, I believe they come with:
- Float bowl gasket
- carb top (better name?) gasket
- Main Jet, rubber O-ring,needle & sleeve
- Slow Jet, rubber O-ring
- Valve seat, rubber O-ring & needle

Is this correct? where is the best place to get this type of kit? about how much do they cost?

Just so I am on the right page here:
- Main Jet #100 = Ok
- Slow Jet #40 = works... but would be better at #38
- Valve seat and Needle #18... #1.8? (couldn't tell if there was a decimal there) = Ok?
- Throttle valve #103 = Ok
- Throttle needle #272304 = Ok

I will be working more on the carbs in a couple of hours, the whole bike is at my parents place (sadly I am in an apartment and do not have a garage or yard for this stuff ) , So I am shuffling back and forth between there.

[TwoTired]

I don't like to use steel wool on aluminum.  Promotes corrosion due to dissimilar metals.  Add electrolyte (impure water) and you have a tiny battery that sacrifices metal to make electricity.

I've not used varsol.  Will that dissolve fuel deposits?  I use those aerosol carb cleaners, with the red tube taped to the side.

I think your carb internals are ok with the stock air box.  The 40s are of concern.  You'd be better off with the 38's.

Carb gaskets:

[TwoTired]

I forgot about the fuel filter.  It should be atop the fuel petcock.  Kind of a sock mesh thing on a nylon base with the stand pipe.  The base is D shaped and has a special gasket.  The big nut on the petcock gets you into it.

Cheers,

[Pawsoff]

Ok, I went to the hardware store and purchased a 4ft (shortest length they had) 1/8" hardwood dowel. After cutting off a 5" piece and tapering the end with a razor some I was able to tap out the brass sleeve under the main jet, it had some crud in there... not a lot but some.



I have 2 carbs totally dismantled at the moment, the second one was much easier than the first which was a bit of a learning experience. I may be posting a pic in a day or so as I have a couple pieces that I don't know where I got em from during the disassembly, most likely from the bracketing holding the 4 carbs together. I am using numbered ziplock baggies to keep the parts separate for now. I purchased some Varsol to soak the carbs in overnight (well 2 of them at least for now) will see if this works or not





I purchased some 00 steel wool to refinish the exterior of the carbs a bit while I am working on em, figured I would after I finish cleaning em.





I don't think this will hurt them as it is only the exterior and should have not more effect than when someone polishes their carbs. If it doesn't work, I am only out 6 dollars and I can use the varsol for some other project later.


I was able to source some Keyster Carb kits for fairly cheap at this site http://olypen.com/retro/
the cost for all four kits including shipping to Canada is about $51
The KH-0128 kit includes the following (see pic below), I verified the Jet sizes with them and they said they were #100 and #38 (I did not say want I was looking for, numbers wise  )



That looks like it covers the hardware, gaskets and o-rings needed... with the exception of the T's holding the carbs together (if memory serves they didn't look bad).OOOOooo one other thing while I think of it, the rubber hose connecting the carbs just above the T's, what size is it? I assume it has to a fuel line?

Pawsoff

[Pawsoff]

Just ordered the keyster carb kits, grand total came to $50.38 USD, very quick replies from the people at http://olypen.com/retro/ I have a good feeling about them, has anyone else dealt with them before? I feel like its a deal because a lot of places were asking $29 per carb without shipping 

I was able to get in about an hour of work on the carbs this morning, the varsol does not seem to be eating up the gunk like I had hoped. But on the "bright" side, it did not hurt em and provided a "wet sanding" type of process when I used the "00" steel wool on one of the carbs, I was very cautious at the start, I have traditionally only used the "SoS" type of steel wool on things, but this fine stuff, man I think I am in love with it :
I was just trying to get the gunk and oxidation off the outside of the carbs in preparation of possible polishing of them later on, the steel wool did a good job, its a early shine but shine none the less, it seemed quite gentle, I did the outside / gasket surface and interior of the carb top plate and fuel bowl. I didn't have time to do the carb body or have my P&S camera with me so I used my cell phone to take a pic for you all. At least this small shine work will give me something to do while I wait for the carb kits to come in.





The pics don't really show how much shine they actually got from this quick job

Pawsoff

[TwoTired]

Unless you measure the new needle's taper profile and it compares favorably with the the old ones, I'd suggest you reuse your old slide needles.  Other's on this forum have reported mixture issues with replacement needles that were solved by going back to the stock needles.  Here are the measurements I took from a needle using a digital caliper.

Jet needle OAL   5.57cm
Jet needle diameter at tip      1.25mm
Jet needle diameter at 1mm   1.63mm
Jet needle diameter at 2mm   2.06mm
Jet needle diameter at 3mm   2.49mm
Jet needle diameter at 4mm   2.52mm
Jet needle diameter at 5mm   2.55mm
Needle jet orifice                  2.60mm

What's done is done.  But, for what it is worth...
Steel is harder than aluminum.  So, are the bits of steel in steel wool.  Small bits of steel from the wool embed themselves into the soft aluminum (you'll need a microscope).  When moisture comes along you get galvanic corrosion, despite the natural aluminum oxide that forms a protective layer over aluminum surfaces.  Aluminum surfaces look great right after steel wool cleaning, but deteriorate quickly with out frequent follow up cleaning/polishing.

The stock top covers were clear coated to extend the shiny qualities.  But, there were no steel particles embedded in there beforehand.

I prefer "scotchbrite" pads for cleaning aluminum.  Polishing compound if you want it shiny.  And, if clear coating, aluminum oxide paper for putting a satin finish on beforehand.

Cheers,

[Bob Wessner]

I second the taper issue. I purchased keyster kits for my 750. Even eyeballing the needles in the kit against stock showed a difference. Kghost (I think) suggested finding a drill bit gauge and checking them by dropping them in various holes. Sure enough, the keyster needles were quite different. Went back to stock with all the hard parts in the carbs and it runs fine.