Topic: 1977 CB550 K cafe racer build

[Zaipai]

who would want crabs?

~Joe

Me, I can deal with them, the EFI not so much.. Make no mistake they will need attention one day..

.: Scott :.

[Zaipai]

Ordered some 102 main jets yesterday, and Zaipai has been kind enough to mail me his vacuum syncronizer on loan to help get this thing DONE!

Thanks again, Scott.

~Joe

Your welcome, hope it helps you out..

.: Scott :.

[traveler]

That's basically how I do mine, except, I turn the motor over until the tappet adjuster is at it's HIGEST point in the hole.  Works every time!

~Joe

[Laminar]

That's basically how I do mine, except, I turn the motor over until the tappet adjuster is at it's HIGEST point in the hole.  Works every time!

~Joe

But judging by the order in which you were marking off "finished" tappets, you were rotating the engine more than necessary. Because of the shape of the cam lobe, there's a generous window of time that each tappet sits at its highest point.

[traveler]

yea, that's true....but when your lsitening to music and drinking beer, it's all fun!

The job got done, and my cam chain is tight too!

Now....let's get those carbs vacuum sync'd and jetted!

~Joe

[traveler]

Zaipai (Scott) let me borrow his carb vacuum syncing setup....didn't know it was BRAND NEW!  So I had to set it all up.  I got it all connected.....









And set the tank up higher with a fuel line stuck in there to get the fuel to the engine.




Then I started the bike up and tried to sync them.  Long story short I spent FOREVER trying to get them right.  As soon as you get 3 of them right where they are supposed to be, you go to adjust the 4th one, and the engine tries to die, so you turn the throttle stop up and try to adjust it, and once you do, the other 3 are now off!  So, all I managed to do was over heat my engine severely, and had to pour 1/2 qt of oil in her as she burned it!  I put the air screws back at 1.5 turns and now she won't start, so I will turn them back in 1/2 turn.

I need to read up on how to do this, instead of trying to figure it out myself.

Anyhow, that was tonight.

~Joe

[Zaipai]

Cool, at least you got them to work. I suspect there is a trick to it so its good that you are going to look it up. I know my carbs are not spot on but they are so good I choose not to muck with them until this winter. So I am glad you are getting some use from the gauges..

Keep us posted please..

.: Scott :.

[Steve_K]

Try using a fan blowing on the cylinders,  as the engine gets hot I think it also gets harder to adjust the carbs.  I also pull the fuse for the headlight so the battery does not go down. A flat battery can cause running problems, too.  Either carb #2 or carb #3 is the master and you may not want to adjust that one.
The good thing is that these carbs stay adjusted for a long time.  It will come, and the bike still looks great!
Steve

[traveler]

Thanks!

I saw a YouTube vid of a guy who set his at 4,000 RPM versus idle.  I might try doing mine at say 2,000 RPM.

~Joe

[Little_Horse]

On four cylinders carb sync can be hard. You need to make very small changes one carb at a time, so basically don't try and get one carb to immediately match the master carb instead try and adjust all of other three close together adjusting all of them slowly until they all match the master. If that makes sense, you will get it to work. +1 on the fan. You might not need it if you are fast but since you are still learning it will help things a lot. Also if there are any vacuum leaks in the intake boots you will get irregular readings.

[traveler]

Ya.....you're right, and I figured that out!

The trick when doing this, I have learned, is to have all 3 locknuts loose, and make 1/4 turn adjustments to EACH carb while watching #2 cylinder, as it's the fixed one (no adjustment, so all must match #2).  Only by going back and forth, back and forth, 1/4 turn here....1/4 turn there....ok...now back this one off 1/4 turn....add a 1/4 to this one....and at some point you hit equilibrium, or close enough that it will work fine.

In short, I got it done!  And now I know........they must be 1/4 turn adjustments....you can't do one carb, set it and go to the next....they don't work that way!  All must be adjusted at the same time...small steps...then set the locknuts and make sure they are still good.

I'm SOOOO glad that's over....now on to fine tuning the air screws for idle, and then main adjustment if needed....battery is on charger as we speak!

And I did it quick enough so as to not overheat my poor little 550 motor!

~Joe

[Zaipai]

Cool Joe, I knew you would get it done..

Gratz!

What RPM where you at? Idle?
.: Scott :.

[traveler]

1250 RPM.

Slight bog off idle, and not quite crisp enough at higher RPM's....runs out of guts around 7500-8000 RPM, but bike is EASY to ride!

Thanks again for letting me use the sync gauges, Scott.

~Joe

[Zaipai]

Anytime.. You think that was hard, try syncing a 81 GS1000 those carbs are a big pain in the ass!!! Your welcome perhaps what you need is a 4 - 1 exhaust for those higher RPM's... 

.: Scott :.

[The_Crippler]

Anytime.. You think that was hard, try syncing a 81 GS1000 those carbs are a big pain in the ass!!! Your welcome perhaps what you need is a 4 - 1 exhaust for those higher RPM's... 

.: Scott :.

Good to know, as I've been wanting one for years...

[Zaipai]

Anytime.. You think that was hard, try syncing a 81 GS1000 those carbs are a big pain in the ass!!! Your welcome perhaps what you need is a 4 - 1 exhaust for those higher RPM's... 

.: Scott :.

Good to know, as I've been wanting one for years...

If you get one.. go here lots of good info, its the SOHC4 for GS's. The O ring between the head and the carbs goes bad fast and lets air seep in quickly and causes the engine to run really crappy.

http://www.thegsresources.com/

.: Scott :.

[traveler]

Well, I had some good luck today!

I FINALLY got the bike running GREAT!

But, It happened in an unconventional way.  After numberous plug chops, I decided to see how it would work to block off some of the pods to order to see how things worked....SUCCESS!  So....various combinations, and I was able to cover some of the pods.....some a tad bit more than others, fine tuning it via airflow, but got it to where she runs great until she runs out of "spunk" at 8,000 RPM....so that's plenty for me. (EDIT:hmmm....you can never have enough though...can you? )

Here are some pics of how it looks.





Here are a couple pics of the bike after taking some black hills 35 MPH sweepers at 55-60MPH....WOW!  She handles GREAT!





Took 6 months to get the build done, and I want to thank ALL who helped, in any way they could to get her done!
 
~Joe

[traveler]

I'm "officially" calling her completed.....but...of course....reserve the right to change things from time to time as it suits me...nevertheless she is a complete cafe racer!

I would like to at some point do the 6 hour drive with the racer in tow, and drop off the bike with Hondaman to let him see if he can "fix" any of my amateur mistakes that are costing me any power.  As I stated....it runs "good enough"....but if any more is available out of my current setup, I'd be all for it!

Also may go to a 4-1 MAC pipe in full chrome (and then give it the brushed look, via scrub pad and wd-40).  Gave up on the Turbo business.....

~Joe

[Bamboozler]

Slick way to give yourself individual cylinder tuning control Joe, I like it!  Glad you got down to the bottom of your tuning and found the motor's sweet spot!! Now time to take it all apart and throw you're turbo idea into motion....    I kid, love up the bike!

Jason

[traveler]

Not that I wouldn't love a turbo...but ATP 550 kits are Unobtanium....so I'll just live with it Naturally Aspirated.....would be nice to have 100 HP, ....but oh well.

Thanks for the kind words.

~Joe

[tweakin]

Great to hear Joe.  I just finished fine tuning my 400 twin and it is a great feeling.

[Industrial Cafe]

I know I said it before but, I really like the way the wheels finish the look of the bike.
 like when you put on a 3000 dollar suit and you finish it off storm trooper cuff links.        (I <3 Star Wars)  


   It feels "factory race" when you look at it.
 I wonder if they were polished and chromed, if it would flow in concert with the tank and seat. or if it would be too much...

OOH! they're silver... how bout these reflective strips?!

[Zaipai]

Gratz Joe! She looks awesome! Bet she is a dream to run...

.: Scott :.

[traveler]

I'm thinking about making a "log" intake with a single Mikuni 42 HSR carb.

Opinions?

~Joe

[Retro Rocket]

I'm thinking about making a "log" intake with a single Mikuni 42 HSR carb.

Opinions?

~Joe

There are problems with this type of set up Joe, you usually end up with, depending where the carb mounts, for the sake of my reply we will say in the middle of the "log" manifold, it will cause the centre 2 ports to receive more gas than the outside ports. It has been documented somewhere on this site before....

Bikes looking great mate...

Mick