Topic: CB 550F Adventure Bike

[Bankerdanny]

The '77 550k was stock with the standard PD carbs, points, air box and filter, sprockets, the original 4-4 exhaust (it was a 7k mile time capsul bike when I bought it, even had the original tires and tubes on it). The replacement tires were (I think) Kenda's 100/90-19 front and 110/90-18 rear. Per the GPS on my phone the speedo was pretty much on the money.

My current 550F has stock carbs (although I can't speak for the jets because I haven't been into the carbs yet), pods, and a Kerker 4-1. It has Lesters with 110/90-19 front and 130/80-18 rear. I haven't looked at the sprockets, so I don't know if the gearing is stock. I also haven't confirmed the speedometer accuracy yet, but the odometer seems to be accurate based on my trips to work and other places where I know the mileage.

[MD]

I guess I'll have to blame my mileage on driving style.

-MD

[MD]

Added a set of highway pegs to the crash bar.  An inexpensive pair from 4into1 that will let me know if I will like using them.

-MD

[MD]

Time for an update on the fish tailing that I have been experiencing.  I am including the below post from technical questions.

With the bike on the center stand, I tried wiggling the rear tire top and bottom which did not a have any play so the new bearings are holding up well.  I also tried left to right and did not get any wobble so the swing arm also appears to be in good shape.  After putting blocking under the front of the engine,  I tested the front wheel for wobble and found none.  The fork also seemed solid.

camelman,

The sugestion about the bearings was correct.  It was not evident until I decided to tighten the chain.  The seal inside the sprocket around the spacer was damaged.  This lead me to taking the tire off.  From lack of experience, I did not pay attention to the fact that the bearings had two different inner diameters.  The brake side fit snugly around the axle.  The drive side is at least a 1/4" too big.  I had ordered the bearings as a kit.  Looking at the parts digagram,  42620-323-030 Collar, Rear Axle Distance and 42625-283-000 Collar B, Rear Axle distance, appear to be between the bearings.  Neither part is was in the hub when I took the original bearings out.

It has taken some searching but I have found a salvage yard to supply the missing spacers.  I have also ordered replacement bearings.  Hopefully I will have both sometime next week.

On a more pleasurable project,  I have started painting replacement side covers.  They will be blue similar to the tank but not exactly.

-MD

[MD]

Received new decals for the side covers.  When taking a closer look at the covers, I noticed some flat spots that don't show the metal flake.  I am going to take some 400 grit paper to those spots Saturday and repaint.  Decals will have to wait another week.

-MD

[MD]

Work got in the way of the best laid plans.  So a day later than planned I got the intake boots on.  When putting the main tank on I discovered I still have plumbing issues to work on.  The Y fittings are causing the tubing to bend to tight.  What I really need is a fitting shaped like this.
 

End result is I disconnected the  aux tank and connected only the main tank.  The bike fired up easily and did not take long to warmup.  Thanks harisuluv.  Idled near a thousand.  Took a six mile run.  Tomorrow I'll put some miles on and see what kind of mileage it gets.

-MD

I was able to get some 1/2 x 1/2 bronze stock from a local sculpturer.  On three faces I drilled the passage.  I also drilled a counter bore for nipples from the Y fittings I had purchased.







I originally planed to use silver solder to add the nipples but have discovered that will not work.  Next steip will be learning to braise.

-MD

[MD]

  Both the missing spacers and the new bearings came in the mail yesterday. 

This afternoon the bearings were removed, spacers installed, new bearings installed and remounted on the bike.  During the test run, I had no wobble when clutching.  The run was on 2 lane highways and gravel.  It is nice to have a ride able bike again.

-MD

[MD]

Installed an Omni-Cruise today and went for a ride to test it out. 



The ridged rubber band supplied with the cruise was not needed on the stock grips.  I did leave on the grip to keep the omni aligned correctly.  You do have to remember to roll the throttle off, otherwise you will have excessive revs when pulling in the clutch.  It was nice to be able to move the right hand and not have the bike decelerate.

-MD

[MD]

Got the XYZ fittings completed.  I used JB Weld to set the nipples inplace.



The problem is that things are still a little too tight between the petcock and the engine intake.  Time to come up with another option.

Took the bike on a 140 mile round trip.  When following normal traffic indicated speed was about 65 in a posted 55 zone running about 5000 rpm.  I did come across some slower vehicles.  I am still getting use to the power curve and gear selection for passing/overtaking.  The first car was on stretch of road that was clear for two miles so I just rolled on the throttle in 5th.  The second car I had downshifted into 3rd the bike seem to stop accelerating at 8000 rpm.  The third car I started in 4th and hit 80mph before backing off on the throttle.  Definitely a little different that hitting the throttle after turning out on the highway.

-MD

[MD]

In an effort to make it more comfortable when standing up, I added 1 1/2" risers.  Previously when standing up my face would be hanging over the front fender.  Had to loosen the banjo on the front brake to get a better angle.  The brake cable is still tight and I may have to replace it.

-MD

[MD]

Went for my first night time run on Friday since removing the old fairing.  Found out the head light was aimed way too high.  When I checked the bucket bolts I found that they were loose.  Re-positioned the bucket and tightened. 

Auxiliary power is in the works.  Picked up a weather protected unit with 12v and  USB ports.  Did a test fitting.

Side covers finally got the clear coat applied.  Pictures after I let it cure for a couple of days.

-MD

[MD]

[MD]

In an effort to make it more comfortable when standing up, I added 1 1/2" risers.  Previously when standing up my face would be hanging over the front fender.  Had to loosen the banjo on the front brake to get a better angle.  The brake cable is still tight and I may have to replace it.

-MD

Took a 45 mile run today.  48 degrees.  The higher bars let me sit back just a little farther on the bike.  My knees behaved themselves for much longer today.  When I get the longer brake line I will roll the bars back a little more.

-MD

[SOHC4 Cafe Racer Fan]

48 Degrees!? In the daytime?!  It was 90 today here.  Fall weather!! 

[MD]

48 Degrees!? In the daytime?!  It was 90 today here.  Fall weather!! 

3:30 in the afternoon.  Morning would have been much cooler.

-MD

[MD]

Took the bike to the trail head for Eagle Mountain, the highest point in Minnesota.  You can't get there without running on gravel roads.  The forest service road I took in was twisty but had some loose gravel so I took it easy in the corners.

Other threads in the sohc bikes have discussed problems with WOT.  When I first put on the new carbs, I did not experience any problems.  In 1st & 2nd there doesn't appear to be any problem revving up to 8000+ though I did experience a back fire in first, turned onto the road straighten up the bike and then gunned it.   In 4th if I roll the throttle on slowly beyond half throttle after reaching 4000 it will  reach 6000.  If I just give it a full twist it doesn't stall but acts like it is starving  for air and has no power.  In that condition 55 is maximum speed.  If I only use half throttle I can maintain indicated 60-65 without a problem. 

I cleaned the petcock filter.  Checked the air filter.  Next item is to check the valve clearances.

-MD

[RAFster122s]

Typically a backfire is a lean condition, thus your checking and cleaning the petcock filter is a good move.  If the valve adjustment went out due to a locknut or two coming loose can spell damage if the cam were to feed in even more clearance, or burning a valve when it goes too tight. Hopefully you are not going to see it increase the clearance when the nut backs off due to the twist of the threads and vibration.  This would be a possibility. But, I don't think I would expect this to happen.
 Still a quick visual and check of the nuts will likely be tight.

I would check the points after I check the valves...then I would look at the carbs for debris in the fuel bowls. If you find any then you need to clean the carbs and figure out where your debris is coming from to stop it.  Some fuel line can come apart with age or being the wrong type of fuel for that line.  This is especially true on some rubber parts not liking the ethanol in fuel.  It took a bit of time to get carb parts and fuel lines that would not be destroyed by the "new" fuel blend.

Maybe this is at play?

Are your float levels correct for the model carbs you have?  550 FAQ has info.
Could be related to inadequate fuel in bowl or restriction in amount of flow.   Clear tube method is easier to determine the float level...just can't verify it when running at high rpm.

A partially clogged emulsion tube can cause the fuel draw to fail to deliver the fuel volume needed.  Or a blocked main jet...clogged.   So, I would pull the main jet and the emulsion tube is beneath this... pressing on the emulsion tube with a screwdriver tip should dislodge it...  check your jet size if you don't know it.  Write it down in your maintenance log or maintenance manual where you are going to find it when you need it.
Pay attention to the orientation of the emulsion tube as it has to go back in the same orientation.
The emulsion tubes foam the fuel to increase atomization as the fuel is drawn out of the main jet.  Above 1200 rpm the emulsion tube starts working.
that performs this work... The idle circuit is still there, it is the needle rising will be affecting draw and the emulsion/atomization if the fuel coming through the main jet.  As the engine vacuum and air bleeds influence with the needle rising as the throttle is twisted open.  The fuel level around and in emulsion tube lowers  reveals more holes in the tube. The amount of fuel being determined in the main jet opening and the needle clip position.

So, check your valve setting, too tight (below the clearance setting) and valves burn...
Check your timing
Check your fuel filters for sedimentation.
check your fuel bowls for sedimentation, if fuel lines are old consider replacing, check float /fuel bowl level,  check main and emulsion jets for any signs of clogging.
What clip position is the needle in and which model of Keihln carbs?

[mothgils]

What tires are you running?

[MD]

What tires are you running?

Dunlop Gold K70s front and rear.

RAF122S,

Thanks for the ideas.  I was thinking lean but adding some choke does not seem to perk it up.  On a ride I took just as this was starting to happen, the rider behind me said he thought the exhaust smelled gassy.  The hoses were supplied by harisuluv. I should have some time later this week to do some more troubleshooting.

-MD

[RAFster122s]

MD,   You ever get this resolved?   I guess a more obvious problem could be the boots for the carbs are not on correctly or tightly enough or they have a crack.
Repro parts are available and they are far cheaper.  I don't know how good they are, but I am sure some here have used them.  Start a thread asking about the repro (reproduction, not repo - repossession) carb boots.

[MD]

MD,   You ever get this resolved?   I guess a more obvious problem could be the boots for the carbs are not on correctly or tightly enough or they have a crack.
Repro parts are available and they are far cheaper.  I don't know how good they are, but I am sure some here have used them.  Start a thread asking about the repro (reproduction, not repo - repossession) carb boots.

Sadly to say yesterday my truck decided not to start after going to the hardware store to pick up a culvert. I had to leave the truck & trailer there while waiting for the truck to be towed.  So the nice warm sunny day did not see me looking at the bike.  The manifold boots are new as well has the airbox boots.  I'll be riding the bike to get to my customers tomorrow.  When I get home with the engine warm I'll tighten the manifold side.  I run non-oxygenated gas in the bike, 91 octane.  I did put some seafoam in the primary tank today which is the only one currently plumbed in.

Most of the leaves are off the trees,  If memory serves me correctly from when I lived in KY you should still have some color.

-MD

[RAFster122s]

MD,  sorry to hear about the truck...hopefully they can fix it quickly and inexpensively.  Hope the trailer remains unmolested as well.
Yes, getting some good color in places and peak or near peak in many mountaneous areas now or the past week.   We had huge temp drop as Low pressure system out of NW blew through...going to be back to.high sixties and low 70s tommorow and next few days.  We typically are at around 65 F in day and around 40 at night.

Not too many warm days left Inam afraid... I really don't look forward to winter.  Moon has been gorgeous past few months and the cold air does bring in much better star gazing opportunities.  Forgot to go out to see the spacestation that passed over a week or so ago...  Satellites and the spacestation are fun to watch transit the sky frome one area to another.  Fun to see around dusk where they pick up the sun and as the approach the other horizon the fade and wink out.

Hope the bike ride is enjoyable and without issue.
David

David

[MD]

Frost on the ground this morning.  First stop of the day was 15 miles at 2 lane highway speeds.  Thermal underwear under the slider cargo pants and a lined jacket made it bearable. 

Hitting the gas after getting pointing straight down the road in 1st.  The bike acted like it skipped a rotation of firing. 2nd did  behaved much better.   Ran both up to 7-8000 rpm.  Upon getting home after the return trip I did find the clamps on some of the intake boots loose.  In the afternoon which got up to near 50, I ran the bike up to red line in 2nd, shifted to 3rd and ran 6500-7000 rpm for 7 miles twice.  I came across a car going slow enough to pass.  I put it in 2nd and red lined the bike.  No evidence of a problem.  The vibrations at those RPMs does make one wonder.

These experiences indicate to me that the problem is not a WOT problem with the emulsion tubes  but rather a fuel air problem that doesn't show itself unless the bike is under a heavier load that you get in 4th and 5th.  When running 4-5000 rpm the bike does surge at times.

I really need to get the valve clearances checked so that I can sync the carbs.

-MD

[RAFster122s]

Hoses aren't a problem then...  Most all hoses you get today for fuel are ethanol compatible.  I could be that you are dealing with a too rich condition...  I have had a mower backfire when I didn't reduce throttle before shutdown because it still had enough fuel vapor in the exhaust and most likely the cylinder that wasn't fired that it was able to fire from heat. 
You could run too lean with the carb bowls not refilling fast enough... shut off the petcock and pull the clutch and shut down the motor with the kill switch and coast to the side of the road when it has been running at speed.  Then you can pull the carb bowls (using a hex screw that is a button head can make float bowl removal on the side of the road much quicker and easier...  A hex key for those in the middle and a hex socket of that size for the outboard ones can speed that process.  It isn't a ton of room to work but trying to get the bowls off with screw heads as original is really difficult many times.    Then you can see if you have an equal amount of fuel in the carbs.   It is possible your float height is wrong causing the lean out condition.
Sometimes you will see too much restriction on fuel filters and that causes the flow to be reduced to the float bowls and they can't refill quickly enough causing a leaner condition to happen.
If you filters are getting junk in them you can see (provided they are clear filters) then you need to address the source of that problem.

A plug chop on a new set of plugs you install and then zoom out to the highway to run at the speed your are getting the problem and then pull clutch and kill switch and coast to side of road...
pull the plugs and check the color.   Reinstall if OK...  Then you can know if you are running too rich or too lean on one carb.
All your exhaust header pipes are equally hot...no cold pipes right?

Typically at highway speeds the 550 tends to be rather lean burning.  This is part of the flat spot if I recall correctly and the fuel needles and jet sizes contribute to this condition as well as the spark advance runs out of ability to influence the spark timing.
HondaMan's recommendation to cut off a coil or two...forget the instructions in 550FAQ, and then reform one coil to serve as the new end so you get a little more tension and extend the spark advance function helps a little for that.  Provided someone didn't already do that to the bike...
 
Probably not an emulsion tube issue at all then...
Air leaks on the boots can definitely cause the issue.  The surging could be fuel levels varying.  If you haven't synced the carbs, then do so first...that could very well be your problem.  Set or check your valve clearance...basically go through a 3000 mile tune without the replacement of parts.  Is your oil smelling like fuel?  How long are your running the bike...getting them up to temp to burn off any fuel dilution of the oil is important...short rides don't work for that...
Carb sync issues could be the root of this problem.  It is amazing the difference it makes, even on a twin cylinder bike having them sync'd up really makes a difference.

I loved SU HS6s on my old '66 Volvo but the tweaks and starting in winter really were a pita until I started running a block heater after the temps started going into the 30s at night and I didn't have to run choke very long at all and the car was warmed up so much faster.  On those sub zero days it would even start...
So, sometimes with the air cooled bikes in cold temps they need more time warming up before going...starting it then finish suiting up with helmet and gloves and doing checks of the lights and turns and even the chain are a good habit to develop in cold weather.  Unless you are pulling it out of a warm garage, then you don't have to wait as long...
David

[MD]

I have had a busy schedule and haven't been able to take advantage of the warm days near 50 when the average is 38.  Filled the bike with gas, pulled on the highway shifted into 2nd, chain came off.  Put the bike on the center stand and was able to roll the chain back on the rear sprocket.  Eased on the highway up shifted to 2nd chain came off again.  This time I had a little more room to get off the road.  Put the chain back on and noticed the chain adjuster rotated counter clockwise 70 degrees.  After taking the adjuster bolt out, I was able to use a crescent wrench to rotate it back into place.  After putting the adjuster bolt back, I was able to ride home. 

Now I am curious as to how the adjuster got rotated.  Was it when the chain came off?  Or had it gotten knocked out of its divot sometime causing the chain to be loose.

-MD