Topic: cb550 -- first project

[JoeP]

This arrived last week:



But before everyone get's their hopes up, I am a noob. This is my first bike build. I bought this cb550 to so I could learn how to build up a bike having never done this before. It may never get finished, or I may completely f... it up and sell it for parts, in which case I hope you enjoyed watching my little train wreck. So if you're willing to watch me learn, struggle, ask lots of stupid questions, run into dead ends, cry in fetal position, overcome, rejoice, and hopefully finish this thing, then here we go...

Ok, I do have a little experience. I taught myself how to do a valve job on, and tune up, a Ducati 749. But I have no experience with carbs, points, engine rebuilding, suspension work, rewiring, painting, welding, and a few other things I want to do with this bike. First order of business is getting it tuned up and running safely. The bike runs now (I rode it around the block), but it's rough, lacks power, and pisses gas out the drain tubes.

First thing I did was to set the tappet clearances (0.002" intake, 0.003" exhaust). Then I checked the compression.  Pulled all plugs, hooked up the gauge, wide open throttle, no choke, cold engine, hit the starter. I got 140-130-120-110 in that order from cylinders 1-4.  Seems like a big variation (>10%).  Put a bit of oil in cyl #4 and compression went up to 125 (needs new piston rings?). Point gaps are also a bit tight but I can't mess with them yet because the adjuster screws are stripped. I haven't cleaned and synced the carbs yet but that's next. 

So here's the first stupid question: given the compression numbers, is a top-end rebuild in order or should I wait to see how the bike runs with clean carbs before worrying about it? Is it also worth doing a leak-down test?

[SOHC4 Cafe Racer Fan]

Pretty good looking bike cosmetically, except for the Harley-wannabe handle bars.  You have a good sense of priorities -- tuning the bike and making it safe first.

[Steve_K]

Gee, if you did a value job and tune up on a Ducati 749,  a CB550 is a much simpler machine to work on.
These Hondas have been around for 40 plus years and the forum has many people who know these bikes very well.
Ask and we will respond.

Have fun will the project.
Steve

[Bankerdanny]

Looks like a great starting point. The nice thing about a 550 vs a 750 is that you can get the head and barrels off without pulling the whole engine.

[JoeP]

Pulled the carbs off today. It took about an hour to get them detached from the engine couplers but in the end...



Carbs looked like the PO already cleaned them so that will save me some time. Just need to blow air through all the jets and recheck the float height.
I also found out my ignition timing was off and couldn't be corrected by moving the plates. So now I'm looking to get an electronic ignition for the bike.

Looks like a great starting point. The nice thing about a 550 vs a 750 is that you can get the head and barrels off without pulling the whole engine.

Thanks. That's good to know since I'm planning to rebuild the top end to get my compression closer between cylinders.

[TerryK]

You are heading in the right direction!

The Dyna electronic ignition is great, easy to install and if it was any lower priced it would be free.

[goldarrow]

I also found out my ignition timing was off and couldn't be corrected by moving the plates. So now I'm looking to get an electronic ignition for the bike.

This means points gaps need to be adjusted. 

[Toustic]

Definitely subb'ing  for this.
I'm in the same boat as you as it seems.

I'm gonna love and hate it, driven by non-sense and ego, but I sure as hell can picture it in my mind right now 

Looking forward to seeing you take on a cb550 as a first build alongside me.

Best of luck,
Toustic

[WhyNot2]

....scribed.....maybe someday I will find a 550.

Can't wait to see what you do...............kewl.

[2strokeTrush]

Saw this on Maryland Craigeslist and the guy was interested in trading me for my cb350f ,but i wasn't.  Glad to see a member here got ahold of it!

[JoeP]

Wow, people are actually watching this. Nothing like another set of eyes (or a hundred!) to make sure everything goes well, and to keep up the pressure on me to do a good job!

I did a little more today. I set up my lonely workspace:



The shiny Christmas tree has lights and makes me happy. Worked on disassembling the carbs and took some pictures to remind me how they're supposed to go back together.





I'm reminding myself that the slow jets go to the right of the main jet for carbs 1 and 2 (left side for 3 and 4):


Here's a carb head disassembled and laid out in the order it's supposed to go back together:


This made my head hurt so I stopped here for the night and had a beer.

Note: the two screws on that "thingy" inside the slide (you know what I'm talking about) were stuck and I was afraid of stripping them. So I fashioned my own impact driver which was nothing more than me tapping on the butt of a phillips head screw driver while I applied a small bit of torque. Sprayed it with some Liquid Wrench first. Worked like a charm.

On flickr: http://www.flickr.com/photos/pinoy1x1/sets/72157639060130856/with/11576872936/

[JoeP]

Saw this on Maryland Craigeslist and the guy was interested in trading me for my cb350f ,but i wasn't.  Glad to see a member here got ahold of it!

Cool! I jumped on it as soon as I saw it. Good to find someone from my neck-o-the-woods on this board as well.

[JoeP]

This means points gaps need to be adjusted.

Thanks. I noticed that the points gap was < 0.010 when I measured it (spec is 0.012 - 0.016), so I widened the gap a bit. Maybe I will put it back to how it was and see if the timing gets better.

[JoeP]

Definitely subb'ing  for this.
I'm in the same boat as you as it seems.

I'm gonna love and hate it, driven by non-sense and ego, but I sure as hell can picture it in my mind right now 

Looking forward to seeing you take on a cb550 as a first build alongside me.

Best of luck,
Toustic

Do you have a project thread on this forum? Send me a link!

[Tews19]

Nice work and bike... Welcome to the site as well...

In your pic of the bottom of the carb bowl you point to the slow jets... If you look where the main jets went, there is the emulsion tube. You need to take that out and clean out the tiny passages. Then do the normal clean of the carb bodies.... What are your plans with the handle bars?

I love 550s and have one now and will be buying another soon as I have a great lead... Damn winter slows the buying process here in my neck of the woods...

[JoeP]

In your pic of the bottom of the carb bowl you point to the slow jets... If you look where the main jets went, there is the emulsion tube. You need to take that out and clean out the tiny passages. Then do the normal clean of the carb bodies.... What are your plans with the handle bars?

Yes, thanks. All the emulsion tubes fell out when I turned the carbs over. Harley wanna-be bars will be replaced with clip ons. Need to figure out throttle/clutch cable lengths. Anyone know? Will also run steel braided brake cables.

[Tews19]

I have never been a fan of clip ons... I like superbike bars and they can use stock length cables.

[2strokeTrush]

Saw this on Maryland Craigeslist and the guy was interested in trading me for my cb350f ,but i wasn't.  Glad to see a member here got ahold of it!

Cool! I jumped on it as soon as I saw it. Good to find someone from my neck-o-the-woods on this board as well.

Yes Sir good new for sure!  Cant be more then 20 or so of us tho 

[JoeP]

Got rid of the Harley wannabe bars today. Not sure if I did it right. I cut the wires going to the LH and RH controls and pulled them out of the bars. Hopefully I can reconnect everything later since I don't want to tackle a full rewiring job right now. I'm planning to run clip ons so I started disassembling the front end. I found an old triple tree stand that works perfectly with the bike's center stand to keep both wheels off the ground. Ignore the floor jack in the pic. I was messing around with different ways to hold up the front.



Was getting ready to pull off the top triple when I decided to measure the fork leg diameter and found this: http://forums.sohc4.net/index.php?topic=132996.0. Hmm. Stopped with the front end dis-assembly and decided to finish cleaning the carbs. I put them in a vat of pinesol last night, and after 24 hours they looked ok.



Will start putting the carbs back together tomorrow. New chain and sprockets on the way. Mentally preparing myself for the top end rebuild...

[JoeP]

I've been getting stuff done, but slowly. First thing done since the last update was to work on these:



The the bottom parts of the legs under the gaiters looked ok, but the tops were corroded. Bought a grinder and a wire brush and was able to get all of the rust off. Filled in the most pitted parts with JB weld and let them sit overnight. Did a wet and dry sanding, then one coat of self-etching primer and one coat of flat black later:



You can still see some rough parts if you look close, but for the most part I'm glad with how they turned out. I also changed the oil and oil seals while I was at it.

While taking off the front wheel, I noticed that the screw holding the speedo cable to the hub won't budge, but I guess this is a common problem. Impact wrench ordered!



The spokes also had quite a bit of rust, but I took care of that with a box of scotchbrite pads and 3 hours of scrubbing:



Got some stuff in the mail too:



along with this seat from Dime City:



That's just a mock up. I'm still trying to figure out how I want to attach the seat to the frame. The underside of the seat is arched, which makes mounting a little tricky, but the seat contours fit the stock frame pretty well, even with the rear seat brace. This is my plan for attaching the seat:



If anyone has experience attaching these seats, I'd like to hear how you did it.

On the way: new tires (irc GS11's) and handlebar switches. Once I get the front end back together, I'll re-attach the carbs, tune up, and ride for a bit to get a feel for the bike. Then I'll think about rebuilding the top end depending on how it runs. Until the next update...

[JoeP]

I started putting the front end back together with the new clip ons and repainted fork legs:



Put the stock gauges on and now the cockpit is looking a little busy.



Luckily, I got a new triple clamp in the mail today from calj737 (BIG_THANKS!) and quickly got to work on it:



After a rough filing, it looks like this:



I'll probably do a bit more reshaping, then sand it down and paint it.

Before quitting for the day I got the master cylinder cleaned up:

[vonvendetta]

You have made excellent process. I'm doing my first built and sure hasn't gone that quick.

Sent from my Nexus 5 using Tapatalk

[CJK]

Looks good!

Have you thought about replacing the rear shocks?
Also, good idea on using the JB Weld and painting fork legs to cover pitting.

[JoeP]

You have made excellent process. I'm doing my first built and sure hasn't gone that quick.

Sent from my Nexus 5 using Tapatalk

Thanks, but I'm really not doing much to the bike. It's in good (enough) running condition that I'll wait for next winter to get into the engine. I'm amazed by the other first-timers who are really getting into it and rebuilding everything.

[JoeP]

Looks good!

Have you thought about replacing the rear shocks?
Also, good idea on using the JB Weld and painting fork legs to cover pitting.

Yes about the rear shocks. But maybe later in the spring (pun intended). Do you have any recommendations?