Author Topic: CB550: This one's a keeper. Two steps forward...one back.  (Read 11344 times)

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Offline OneWheelDrive

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CB550: This one's a keeper. Two steps forward...one back.
« on: April 06, 2012, 11:12:46 AM »
Ok guys and gals, I've been wrenching furiously for the last two weeks on my new find, and I figured it's time to start the real build thread, but first, a little back story:

About a year ago I sold my last 550, and bought the bike of my dreams: Ducati Monster S4RS.



The thing was an absolute banshee.  Handled unbelievably, stopped on a dime, sounded so mean, but after riding it for about a year, I decided that it wasn't the bike for me.  It was a constant exercise in self control.  At any moment, a 1/4 turn of the throttle could mean easy triple digit speeds.  Ultimately, my passion is working on bikes as much as riding them, and it just didn't give me that option.  Any mechanical work required hundreds of dollars in specialized tools and I always just defaulted to having an experienced mechanic do things like timing belts and valve adjustments....no fun!  So, I sold it, and the hunt began again for another SOHC4 project to wrench on, swear at, waste time on, feel proud of, and ride the $h*t out of!

I gotta tell you, finding a deal on these bikes in Southern California is becoming a near impossibility.  Obviously there are still gems out there, but they are increasingly rare.  Just 5 years ago, when I bought my first, I had a hard time deciding which $500 bike to buy.  Now, it seems like everyone wants $2,500 for their rusty "ran when it was parked cafe racer potential project".  I started to find success when I started posting want-ads for what I was looking for and people started contacting me with real deals.  The first real deal came in the form of a 1975 CB360T that a collector was unloading for the garage space.  I drove 3 hours away to look at it, and came home with a near-mint CB Twin for a song.



All it took was about $200 in tires and parts, and about 6 hours in the garage to make it a truly mint, unrestored, all original scoot.  The goal of my search was to find a project to make my own, and I couldn't bring myself to so much as change the handlebars on this one, so it went on the ebay auction block with fairly low expectations of the selling price.  It ended up selling for a hefty $2200 profit that gave me a nice chunk to put into the REAL project.

Then a nice young man contacted me saying he had a CB550 he needed to get rid of to finance an engine rebuild on his sandcast, so I went to check it out.  JACKPOT!!



She was wonderfully disgusting!  Only 9,000 miles, good condition tank and seat, intact exhaust, complete and original.  The good also game with the bad:  a seized front brake, no ignition or keys, frozen motor, varnished tank, some nasty wiring, windjammer fairing, rustoleum rattle can wheels, triple trees, fork lowers, hadn't been started or registered since '79!!  I don't know why, but I love all the challenges it presented.  I counted out 8 $100 bills, pushed it into my truck and drove home dreaming of months of black fingernails and late nights in the garage.  Not exactly a "steal", considering the title situation and the obvious problems, but I won't feel bad about molesting the originality of this one.  It's a blank canvas!









« Last Edit: June 04, 2012, 02:05:38 PM by OneWheelDrive »
1975 CB550 cafe
1971 CB500 stocker
2008 Ducati Hypermotard 1100S *sold*
1973 CB350F *sold*
1975 CB550K Project "Keeper" *sold*
2010 Ducati Monster S4RS *sold*
1976 CB360T *sold*
1974 CB550K *sold*
1973 CB750K *sold*
1978 CB550K *sold*
2007 Vespa LX150 *sold*

Offline OneWheelDrive

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Re: New CB550 Project: This one's a keeper!
« Reply #1 on: April 06, 2012, 11:39:20 AM »
AAA confirmed that it was out of the DMV system, and would be a simple process to get the title.  Whew!

In the next day or so I diagnosed a dozen or so key areas that needed immediate addressing in order to breath life back into it:

Seafoam/ATF soak the cylinders
Master cylinder and caliper rebuild
New filter
New plugs and wires
Oil and filter change
Carb rebuild and tune of course
New fuel lines
New ignition switch
New battery
New headlight ring so I could nix the windjammer
Tappet clearance tune
Timing adjustment
Cam chain adjust

The good news was that it had been stored inside for all these years, and still had plugs in, saving the cylinders from the elements.  After a few days of disassembly as I waited for parts to arrive from all over the place and the motor soaking in a generous cocktail of penetrant, oils, and seafoam, I was able to get the motor to turn smoothly at the crank!

I got the ignition switch in the mail and when I plugged it in and supplied power, I couldn't get any signs of life from the starter, lights, etc, all from the right controls.  The horn and turn signals worked on the left however.  I opened up the starter solenoid, cleaned and reassembled.  Solenoid was functional, starter was functional...hmm.  Then I checked the control itself:



Chopped, but repairable.  It's really so satisfying when you've been scratching your head for hours to find something so simple!

Repaired the wiring and was able to get the starter to spin, and the fresh plugs to fire when grounded!

The next battle was the carbs, and it was one to the death unfortunately.  It took me almost 4 hours do rebuild the original rack, which was much longer than it's ever taken me before.  I got to the fourth carb and was really struggling to get the pin out of the float.  I tried using a plastic punch and mallet, when disaster struck:



Why couldn't this have happened on the first one!?  Anyway, I was off to ebay to find another set of 022A, and got a set shipped for $90.  Not bad.  They were nasty on the outside, but very clean on the inside.  They were missing two idle jets though.  Good thing I had some extras. 

I got the bench synched set re-mounted on the motor without too much difficulty.  The boots were nice and soft, so that made it easy. 

I static timed the points to make sure they weren't too out of whack, easy peasy.

I did a quick inventory: air, fuel, fire, compression?  Hmm, moment of truth time:



SHE LIVES!!!

1975 CB550 cafe
1971 CB500 stocker
2008 Ducati Hypermotard 1100S *sold*
1973 CB350F *sold*
1975 CB550K Project "Keeper" *sold*
2010 Ducati Monster S4RS *sold*
1976 CB360T *sold*
1974 CB550K *sold*
1973 CB750K *sold*
1978 CB550K *sold*
2007 Vespa LX150 *sold*

Offline Teatimetim

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Re: New CB550 Project: This one's a keeper!
« Reply #2 on: April 06, 2012, 11:52:27 AM »
Man that looks lot worse the the one I had that had sat for 17 years.. 
Bikes I own:

1974 CB550K
1971 CB450

Offline OneWheelDrive

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Re: New CB550 Project: This one's a keeper!
« Reply #3 on: April 06, 2012, 11:54:06 AM »
Then I focused my attention on the brakes, and the obligatory battle with the master cylinder snap ring.  I won't bore you with the details, but it was a PITA.  Ended up destroying a needle nose, a Harbor Freight circlip pliers, and an electrical tester probe before having success using a blowtorch and a Home Depot pick set.  Master is rebuilt.  Now I'm just waiting for pads and a caliper piston seal and I should be on the road!!!

The DMV told me I have 30 days from the date of purchase to apply for lost title.  In order to do so I have to get it get to the CHP to have it inspected and VIN verification done.  I now have 12 days to get that done and I'm pretty confident it's gonna happen. 

Then the real fun begins.  I'm planning on a full frame off rebuild with a serious attention to detail.  I'm going to go the mild cafe route, but this is going to be one of those never ending projects.  I'm going to build a blasting cabinet, learn the zen-like ways of the buffing wheel, hone my painting and body work skills, and really end up with something that I'm proud to have put together.  Stay tuned!
1975 CB550 cafe
1971 CB500 stocker
2008 Ducati Hypermotard 1100S *sold*
1973 CB350F *sold*
1975 CB550K Project "Keeper" *sold*
2010 Ducati Monster S4RS *sold*
1976 CB360T *sold*
1974 CB550K *sold*
1973 CB750K *sold*
1978 CB550K *sold*
2007 Vespa LX150 *sold*

Offline theofam

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Re: New CB550 Project: This one's a keeper!
« Reply #4 on: April 06, 2012, 02:16:26 PM »
What a nice start on a great looking project!  You'll be a CB Renaissance man after learning all those various trades along your way toward creating a beautiful scoot!

Thanks for the blowtorch idea on the MC. I'll use that next time I get a stubborn one.

Offline OneWheelDrive

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Re: New CB550 Project: This one's a keeper!
« Reply #5 on: April 26, 2012, 02:13:17 PM »
Alrighty, it's been about a month since the 550 came into my life, and it's been  a challenge to get her to where she's at.  Having not been touched since 1979, it was a mess.  Front brake trials and tribulations, electrical woes, several carb cleanings and retunes, $500 in parts all the standard tuneup procedures, but she's finally running 100%.  I wanted to make sure it was running like a new bike (only 9,000 original miles) before I tried to give her the makeover she deserves. 




Now I'm going to move into my buddy's garage and begin the teardown.  There is so much rattle can black paint and overspray, as well as surface rust that I have to address. 

For the record, I am selling both the stock seat and exhaust, $200 each in the classifieds section.  I have in the mail a 650 cam, drive gear, and tach, CB400F stock rearsets, and period 4 into 1 Kerker that should all be here shortly.  I'm going to have the tank, side panels, and tail repainted the stock "Candy Jet Green".  There's a local guy that does a killer job without using decals.  I want it to be a very clean, but subtly cafed in period correct fashion.

Kinda like this?

And before you naysayers say, "that's too nice to cafe", I must tell you that it is far uglier than you think.  The tank is a disaster up close, as is basically every piece of aluminum, plastic, and steel.  I simply do not have the budget to replace everything that needs replacing.  I have already restored to stock condition a CB500 and a CB360T, and this $800 bike without a title was resurrected with the intention of going a different direction.  I'm going to soda blast, paint, powdercoat and polish everything possible and reassemble.  It's going to be a fun bike to rip around town on and hopefully I make quick work of the rebuild.  Wish me luck!
1975 CB550 cafe
1971 CB500 stocker
2008 Ducati Hypermotard 1100S *sold*
1973 CB350F *sold*
1975 CB550K Project "Keeper" *sold*
2010 Ducati Monster S4RS *sold*
1976 CB360T *sold*
1974 CB550K *sold*
1973 CB750K *sold*
1978 CB550K *sold*
2007 Vespa LX150 *sold*

Offline 4g3tful

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Re: New CB550 Project: This one's a keeper!
« Reply #6 on: April 26, 2012, 03:50:22 PM »
That is going to look beautiful!!!! Nice back story to it too. Happy fixing! Gonna keep my eye on this one!

Offline cmonSTART

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Re: New CB550 Project: This one's a keeper!
« Reply #7 on: April 26, 2012, 03:59:48 PM »
Wow!  Those carbs look terrible!  Actually, my '78 750F project this year and my Goldwing project last year both looked like that. 
1981 GL1100 Interstate
1978 CB750F Project

Offline OneWheelDrive

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Re: New CB550 Project: This one's a keeper!
« Reply #8 on: April 26, 2012, 10:45:57 PM »
Got the CB400F rear sets mounted up!  It's not radical like using the passenger pegs, but moves my feet back about 5 inches, which is all I need to fit comfortably on the seat.



1975 CB550 cafe
1971 CB500 stocker
2008 Ducati Hypermotard 1100S *sold*
1973 CB350F *sold*
1975 CB550K Project "Keeper" *sold*
2010 Ducati Monster S4RS *sold*
1976 CB360T *sold*
1974 CB550K *sold*
1973 CB750K *sold*
1978 CB550K *sold*
2007 Vespa LX150 *sold*

Offline OneWheelDrive

  • A journey of 1000 miles starts with your first carb overhaul.
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Re: New CB550 Project: This one's a keeper!
« Reply #9 on: April 30, 2012, 01:56:48 PM »
Spent about 2 hours wrestling with the rocker cover in order to put in the shiny 650 cam that I got last week.  I broke one breather cover bolt (not a huge deal I understand) in the process, but finally managed to get the cover off, and the cam in.  Unfortunately, once I went to adjust the valves, I was getting valve/piston interference at TDC and couldn't freakin' figure out why!  I loosened all of the valves, turned the crank 360 degrees, and tried readjusting.  Nope. 

Slept on it for a night and approached it with a clear mind at lunchtime today.  Turns out the cam chain was off, not by one, but TWO links.  Duh.  Got it all buttoned up and I'm expecting an easy valve tune process to get it fired again.  I'm hoping I didn't bend any valves trying to turn the motor over with piston contact. 

I've got to get it running tonight, tomorrow is my CHP, then DMV appointments to get the title finally!
1975 CB550 cafe
1971 CB500 stocker
2008 Ducati Hypermotard 1100S *sold*
1973 CB350F *sold*
1975 CB550K Project "Keeper" *sold*
2010 Ducati Monster S4RS *sold*
1976 CB360T *sold*
1974 CB550K *sold*
1973 CB750K *sold*
1978 CB550K *sold*
2007 Vespa LX150 *sold*

Offline OneWheelDrive

  • A journey of 1000 miles starts with your first carb overhaul.
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Re: New CB550 Project: This one's a keeper!
« Reply #10 on: May 01, 2012, 11:13:58 AM »
Goddammit!  Bent valves, crushed spirit  :(  :-[ Missed my appointments at CHP and DMV.  Should have left well enough alone until I got the title.  I was fighting with my chick and worked on the bike while pissed off, made a careless error.  I'm reaching out to the So. Cal 550 owners for a head and/or valves to replace the damage I did....
1975 CB550 cafe
1971 CB500 stocker
2008 Ducati Hypermotard 1100S *sold*
1973 CB350F *sold*
1975 CB550K Project "Keeper" *sold*
2010 Ducati Monster S4RS *sold*
1976 CB360T *sold*
1974 CB550K *sold*
1973 CB750K *sold*
1978 CB550K *sold*
2007 Vespa LX150 *sold*

Offline luceja

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Re: New CB550 Project: This one's a keeper! BENT VALVES
« Reply #11 on: May 01, 2012, 02:39:54 PM »
Goddammit!  Bent valves, crushed spirit  :(  :-[ Missed my appointments at CHP and DMV.  Should have left well enough alone until I got the title.  I was fighting with my chick and worked on the bike while pissed off, made a careless error.  I'm reaching out to the So. Cal 550 owners for a head and/or valves to replace the damage I did....

for me a big part of learning these bikes has been learning to work in the right mindset to avoid problems like this. I recently ruined a cb550 head and valvetrain in a  similar way - working too fast, too distracted. Anyway, I wrote just to say I know how that feels, but somehow the finished product is even sweeter after all the trouble.
'75 cb400f, '77 cb550f , CB160 road racer, '88 Hawk GT track bike, FZR400 race bike, and a bunch of old hondas in boxes.

Offline lucky

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Re: New CB550 Project: This one's a keeper!
« Reply #12 on: May 01, 2012, 10:51:20 PM »
Alrighty, it's been about a month since the 550 came into my life, and it's been  a challenge to get her to where she's at.  Having not been touched since 1979, it was a mess.  Front brake trials and tribulations, electrical woes, several carb cleanings and retunes, $500 in parts all the standard tuneup procedures, but she's finally running 100%.  I wanted to make sure it was running like a new bike (only 9,000 original miles) before I tried to give her the makeover she deserves. 




Now I'm going to move into my buddy's garage and begin the teardown.  There is so much rattle can black paint and overspray, as well as surface rust that I have to address. 

For the record, I am selling both the stock seat and exhaust, $200 each in the classifieds section.  I have in the mail a 650 cam, drive gear, and tach, CB400F stock rearsets, and period 4 into 1 Kerker that should all be here shortly.  I'm going to have the tank, side panels, and tail repainted the stock "Candy Jet Green".  There's a local guy that does a killer job without using decals.  I want it to be a very clean, but subtly cafed in period correct fashion.

Kinda like this?

And before you naysayers say, "that's too nice to cafe", I must tell you that it is far uglier than you think.  The tank is a disaster up close, as is basically every piece of aluminum, plastic, and steel.  I simply do not have the budget to replace everything that needs replacing.  I have already restored to stock condition a CB500 and a CB360T, and this $800 bike without a title was resurrected with the intention of going a different direction.  I'm going to soda blast, paint, powdercoat and polish everything possible and reassemble.  It's going to be a fun bike to rip around town on and hopefully I make quick work of the rebuild.  Wish me luck!

That camera really distorts those wheels in that beautiful side view .WOW

Offline OneWheelDrive

  • A journey of 1000 miles starts with your first carb overhaul.
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Re: New CB550 Project: This one's a keeper! BENT VALVES
« Reply #13 on: May 01, 2012, 11:52:44 PM »
in case you're wondering what two bent-ass exhaust valves look like...
1975 CB550 cafe
1971 CB500 stocker
2008 Ducati Hypermotard 1100S *sold*
1973 CB350F *sold*
1975 CB550K Project "Keeper" *sold*
2010 Ducati Monster S4RS *sold*
1976 CB360T *sold*
1974 CB550K *sold*
1973 CB750K *sold*
1978 CB550K *sold*
2007 Vespa LX150 *sold*

Offline knowsnothing

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Re: New CB550 Project: This one's a keeper! BENT VALVES
« Reply #14 on: May 02, 2012, 06:28:31 AM »
in case you're wondering what two bent-ass exhaust valves look like...

Wow, way not to half-ass anything, even bent valves! 
1978 CB750k Green - 811 engine
1978 CB750k Blue - for sale
1974 CB375F Faded Black - had to have that 6th gear
1976 CB400F Red - in many pieces
1973 CB350F TBD - in many pieces

Offline cmonSTART

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Re: New CB550 Project: This one's a keeper! BENT VALVES
« Reply #15 on: May 02, 2012, 05:46:10 PM »
Wow!  Can't wait to see how the new head goes!
1981 GL1100 Interstate
1978 CB750F Project

Offline lucky

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Re: New CB550 Project: This one's a keeper! BENT VALVES
« Reply #16 on: May 03, 2012, 05:58:02 PM »
WOW!!! Those really got smacked!!

Offline fmctm1sw

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Re: New CB550 Project: This one's a keeper! BENT VALVES
« Reply #17 on: May 04, 2012, 11:27:48 AM »
in case you're wondering what two bent-ass exhaust valves look like...

dude! 
Quote from: 754
Dude is that a tire ? or an O-ring..??

Quote from: inkscars
This is not a pod thread
This is not a #$%* on my vacuum gauges thread
This is a help or GTFO thread.

1973 CB350F
1973 CB350G
1975 CB550K
1983 GL650I
1973 CB750K3 (http://forums.sohc4.net/index.php?topic=92888.0)
1984 Kawasaki KLT-250 (AKA 3 wheeler of death)
1994 Honda TRX300
1999 Honda TRX250

Offline OneWheelDrive

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Re: New CB550 Project: This one's a keeper! BENT VALVES --> FIXED!
« Reply #18 on: May 13, 2012, 11:26:59 AM »
Alright!! So I ordered an OEM head gasket from BikeBandit ($75 shipped) to go along with my $7 used ebay head ($25 shipped).  Got all the parts, cleaned up the head, lapped the valves, prepped the gasket mating surfaces, and reinstalled everything.  She fired right up!

This is the first time its run with the 650 cam and the Kerker with the comp baffle and she screams like a banshee.  It's very obviously running lean on the main jet, evidenced by very white plugs and a major stumble in the mid throttle range.  So I ordered 105 mains that should be here this week.  Along with a raised needle clip, I think I'll be in business.

Because I know Lucky is going to ask:

'75 CB550 with 022A carbs, stock 100 main, 40 pilot, needle in middle clip position, uni foam filter, kerker 4 into 1 with comp baffle.

Here she is all put together and running.  I have since put 650 gauges on so the tach is functional again.

1975 CB550 cafe
1971 CB500 stocker
2008 Ducati Hypermotard 1100S *sold*
1973 CB350F *sold*
1975 CB550K Project "Keeper" *sold*
2010 Ducati Monster S4RS *sold*
1976 CB360T *sold*
1974 CB550K *sold*
1973 CB750K *sold*
1978 CB550K *sold*
2007 Vespa LX150 *sold*

Offline Stev-o

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Re: New CB550 Project: This one's a keeper! BENT VALVES --> FIXED!
« Reply #19 on: May 13, 2012, 01:23:53 PM »
Great project, subscribed.  What's next?
'74 "Big Bang" Honda 750K [836].....'76 Honda 550F.....K3 Park Racer!......and a Bomber!............plus plus plus.........

Offline lucky

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Re: New CB550 Project: This one's a keeper! BENT VALVES --> FIXED!
« Reply #20 on: May 13, 2012, 04:36:18 PM »
I would go to a #42 idle jet if you still have throttle hesitation with the needle raised one position.

Either the needle will do it or the idle jet may solve that transition around 1/4 throttle.

Sounds like you know what you are doing.

Let us know the outcome and i will add it to my database.

Offline mono

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Re: New CB550 Project: This one's a keeper! BENT VALVES --> FIXED!
« Reply #21 on: May 14, 2012, 09:19:10 AM »
good-lookin' job so far, OneWheel!  that "cafe" build that you linked is a real piece of inspiration for me too.

Let us know the outcome and i will add it to my database.

Lucky, do you have this database posted on the forum?

Offline OneWheelDrive

  • A journey of 1000 miles starts with your first carb overhaul.
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Re: New CB550 Project: This one's a keeper! BENT VALVES --> FIXED!
« Reply #22 on: May 14, 2012, 09:48:21 AM »
Yeah I'm pretty amazed I was able to get the top end totally rebuilt in a morning, especially considering how hung over I was!  Playing the waiting game to get those jets in the mail so I can get it running well.  The fuel starvation makes it pretty much unrideable.  I don't want to burn up a valve after all the work I've done! 

The plan is to get it running 100%, and over the summer slowly fab it up how I want it.  Going to make a cafe seat out of an old stock pan, try my hand at vinyl wrapping on the tank, seat, and sidecovers.  Need to get some good braided lines to improve the squishy front brake.  I'm thinking superbike bars as well.  Once I've gotten it physically where I want it, I'm going to do a full frame-off rebuild, powdercoating, polishing, chroming, and de-rusting every part.  The worst part is the rusty, then rattle canned spokes and hubs, but I don't want to tackle that stuff while the weather is perfect!
1975 CB550 cafe
1971 CB500 stocker
2008 Ducati Hypermotard 1100S *sold*
1973 CB350F *sold*
1975 CB550K Project "Keeper" *sold*
2010 Ducati Monster S4RS *sold*
1976 CB360T *sold*
1974 CB550K *sold*
1973 CB750K *sold*
1978 CB550K *sold*
2007 Vespa LX150 *sold*

Offline OneWheelDrive

  • A journey of 1000 miles starts with your first carb overhaul.
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Re: CB550: This one's a keeper! BENT VALVES --> FIXED! Intake Question?
« Reply #23 on: May 14, 2012, 11:59:40 AM »
I just had a thought..... When I ordered the "new" donor head, it came with intake manifolds already attached.  I did not remove them from the head and check the o-rings.  I did check for intake leaks on the airbox side with carb cleaner, but did not check the manifold side for leaks.  Could worn o-rings be causing the lean condition?  I ordered a set of them just to be safe, but now I've gotta pull the damn carbs again to check :-/. 

Also ordered clubmans, NOS barrel grips, slingshot steel brake lines, NOS Halcyon Cafe Mirrors, and a recessed brake light for my to-be-build cafe seat. :-D
1975 CB550 cafe
1971 CB500 stocker
2008 Ducati Hypermotard 1100S *sold*
1973 CB350F *sold*
1975 CB550K Project "Keeper" *sold*
2010 Ducati Monster S4RS *sold*
1976 CB360T *sold*
1974 CB550K *sold*
1973 CB750K *sold*
1978 CB550K *sold*
2007 Vespa LX150 *sold*

Offline luceja

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Re: CB550: This one's a keeper! BENT VALVES --> FIXED! Intake Question?
« Reply #24 on: May 14, 2012, 12:05:31 PM »
I just had a thought..... When I ordered the "new" donor head, it came with intake manifolds already attached.  I did not remove them from the head and check the o-rings.  I did check for intake leaks on the airbox side with carb cleaner, but did not check the manifold side for leaks.  Could worn o-rings be causing the lean condition?  I ordered a set of them just to be safe, but now I've gotta pull the damn carbs again to check :-/. 

Theoretically yup, worn or missing o rings there could pull in extra air there and change everything. It's worth new o rings to confirm that it's no a problem there, at least. Congrats on the quick motor recovery and thanks for posting your jetting process. I'm doing the same but coming down from the rich end of things instead of up from lean.
'75 cb400f, '77 cb550f , CB160 road racer, '88 Hawk GT track bike, FZR400 race bike, and a bunch of old hondas in boxes.