Topic: Strategies for Cleaning and Rust Removal - 1974 CB550

[dmfernandez87]

Hey everyone,

Bought a 1974 CB550 as a project bike to learn and it's completely disassembled. I’m going for the Top and Bottom Engine rebuild next.

I'm in a bit of a analysis paralysis for cleaning and removing rust. I don't mind spending some money, but what are the most economical ways of removing rust and making this bike look great again? Engine, Wheels, Carbs, Frame, etc

What are decent handheld options? Should I be sending this stuff out to be sand blasted? Can I get away with investing in a buffer with some wire wheels? Is a parts washer or ultrasonic necessary ?

Input is greatly appreciated.

The engine was running ok, leaked some oil, and the previous owner kept it on the streets of San Francisco (has 17,000 miles on it). I bought it for $1500 and wanted to use this bike as a learning medium for a restoration. I have the Service Manual, Parts Catalog, and lots of bookmarked YouTube videos + threads. Essentially I'm treating this as an expensive lego set to disassemble and put back together to build some competency and confidence.

EDIT:
Fixed Typo and added additional details.

[newday777]

Welcome aboard

"I’m going for the e
Top and Bottom Engine rebuild next."
What is this "e top and bottom rebuild" you mentioned? Is that a  typo, an extra "e"? Or is that a level of restoration?

There are several rust gel products out on the market to use and are well written up in posts and videos. They aren't miracle makers, Most likely you'll need to repaint the rusted paint parts depending on level you intend to take this project to. Vapor blasting is a better option than dry sand blasting for the better finish before painting steel or buffing aluminum. Buying tools like good vapor blasting cabinets take up lots of space and are costly. Are you on a limited budget or dad warbucks pockets???

There are plenty of posts on restoration techniques using the search functions here in the forum for you to be doing and videos on the web and youtube rather than having us type out the various methods. We don't know your capabilities nor the extent you want to take this restore to.

Start a project thread introducing yourself and the bike with your history and capabilities as well as the bike's history. Did you strip down the bike or did you buy it apart? Do you have the service manual? Ect.....

[ekpent]

What is your long range plan for it stock resto or custom ?

[jlh3rd]

and before worrying about cosmetics , just what shape is the motor and tranny in.
who's doing the work.
Maybe consider finding a bike like this for sale in the mid $3000's.

[Shopdog]

Welcome! Your project looks very similar to my '75 cb550. I just started working on it. I'm a complete newb when it comes to street bikes, but I have been working on old cars, atv's, boats, and just about everything else for many years.

I didn't plan on spending a lot on my rebuild. It has been sitting since 1985 (ish) and was in pretty rough shape. While completely stripping the frame and powder coating is top notch, it's way more work and money than I'm willing to put into it. Your situation may be different. For my frame, I went a section at a time. The rusty areas, I hit with a wire brush on a drill, sandpaper, and scotch brite pads to get the loose rust off. A quick wash down with brake cleaner or whatever solvent I had handy, and then some rust reformer. It's the rustoleum brand black stuff in aerosol form. After that, I used regular rustoleum in aerosol. Tractor & implement paint would work as well. If you're looking for something that holds up better, you can buy aerosol cans of single stage 2-part paint. Eastwood sells it, but there's at least one other brand out there. If you have a spray gun and compressor, you can shoot either rustoleum, tractor paint, single stage 2-part urethane, or base/2k clear. I have all that stuff, but again...more work than I was willing to do. If mine starts looking bad over time, I'll eventually redo it using something better.

Your upper forks look rough. If they're functional, sand the rust off and treat it with whatever you choose. Some stock-style fork covers/headlight brackets will hide it, if you don't mind getting rid of your clip-on brackets.

The engine is painted from the factory. I took a small wire brush, sandpaper, and scotch brite to the whole thing. The fins will keep you busy for a while. I used engine paint on mine, but again, there are plenty of options. The main thing is to clean very well. Any paint is worthless over oily substrate. A good wash down with dawn or degreaser and plenty of brake cleaner helps.

For rusty chrome, there are several YouTube videos that are helpful. Most of them didn't work for my junk, so I replaced handlebars (they're pretty cheap), shocks (the originals are probably toast anyway), and exhaust (I'm going with a stainless aftermarket). My wheels are also ratty, but I'm going to replace them later on. 

I hope this helps give you some ideas. Also, keep in mind that many of these parts are really cheap to replace and just aren't worth spending hours trying to make them look so-so. For example, the chrome on my mirrors were really bad. New ones were around $25 or so. I replaced brake/clutch levers, plenty of hardware, etc. You'd be surprised just how inexpensive some of these parts are to replace... and also how expensive other parts are 😆!

[Stev-o]

First off welcome and consider starting a thread in the "Project Shop" area to document your restoration.

TYpically, it is good to get the motor running first to determine really what is needed but seems your beyond that now. I would bet the bottom end is fine, they are bulletproof.  I've found a good valve job is key to having these motors run great after sitting a long time.

As far as the frame, I would take it to a powder coat guy to blast and powder it.  Semi-gloss black is the factory color.

Good luck

[exponent]

Stock up on scotchbrite and carb cleaner/mineral spirits. Those two will go far in hand and are cheap but also incredibly time consuming. A wire wheel decimates rust but will need buffing after use if you want to remove scratches. Investing in your own blast cabinet can really pay off but it is a rabbit hole of tool collection, requiring a large air compressor, hose, the media of choice and a shop vacuum. Blasting is amazing especially for soft aluminum in refacing surfaces and removing grime, rust and packed dirt. You'll want to start blasting every metal surface you own lol.
A parts washer may not be necessary but a bucket you can fill with some kerosene to use for brushing would be a great help as well.
Ultrasonic is mainly used for carb parts but is an easy way to continue the cleaning and make sure all passages are clear. Not the cheapest however.
For shine and getting the flashy looks back definitely go for a buffing wheel, pads, and products. We built one from an old electric motor and I used tripoli and white rouge on some of my parts, looked amazing and way better than any polishing rag could do.

[dmfernandez87]

Thanks for all the responses! I'll start up a new thread over in the projects section.

Sorry for the lack of details, added info in the opening post.

[Bankerdanny]

Welcome. No need to pull the engine apart at 17k miles unless is it stuck, and even then it might not be necessary. More likely the oil leak is solved by replacing the valve cover gasket and the roughly quarter sized rubber pucks that cover the head bolts under the cover.

The easiest way to get the engine out of the frame is to unbolt it, then turn the frame, engine inside, on its side then lift the frame off the engine. The engine itself weighsless than 150lbs, so one it is out of the frame you can probably lift it up onto a table by yourself.

On my '74 550K project, which has sat for several years because I ended up buying a rider bike, I pulled the engine and stripped everything off the frame except the swingarm (couldn't break the bolt loose). I cleaned and degreased then wire wheeled off any rust and treated with a rust converter then spot primed. Then I painted the whole thing with frame/grill paint from Harbor Freight. It is a satin black and almost identical to the factory paint. I have used it to touch up frames on 2 other SOHC's and you can't tell the difference.

[dmfernandez87]

Thanks again for the input. Supremely stupid question; is it a bad idea to open up the engine to go through the motions of an engine rebuild ? I'm aware there's a risk for new leaks and putting it back together incorrectly. Please don't kill me lol I'm ignorant and trying to maximize this learning experience. I'm treating it like a self paced college course and the money I'm spending is tuition (at a junior college.)

For rust removal, which types of brushes and for which components of the motorcycle should I be cognizant of? (Steel, Brass, Nylon, Frame, Engine, etc) I'm looking at these on Amazon for my drill:

https://www.amazon.com/LINE10-Tools-attachment-Removing-Impact/dp/B07B5349NL/ref=sr_1_5?crid=1DZV6WD0IUOM7&keywords=wire+brush+drill+attachments+for+rust&qid=1645230187&refinements=p_85%3A2470955011&rnid=2470954011&rps=1&sprefix=wire%2Bbrush%2Bdrill%2Battachment%2Caps%2C165&sr=8-5

When the rust is removed, next steps are to use a rust converter, prime, and then paint ? Any recommendations for these chemicals?

[seanbarney41]

It should be pretty easy to find an engine that you know NEEDS to be rebuilt.  Use that as a learning project.  A junked lawn mower motor has all of the same basic components.  Consider the fact that these engines were extremely well built from Honda and that really, there are few people left in the world that have access to the knowledge, machinery, and parts to put them back together again as good as Honda did in the first place.  You can learn a hell of a lot by getting and keeping this running and using it as was intended.  Just my opinion for you to consider.

And before you go power drilling all over all kinds of stuff, wash it!...by hand...use some sweat and blood to see what you got.  Let that old bike be old.  It's gonna be a lot cheaper and easier to buy a brand new motorcycle at the dealership, if that's what you want.

[dave500]

get mollasses,mix it well about 50/50 with hot water,place any steel or ferrous items in it,you can leave them as long as you like,itll strip rust but halt at good steel,things like special bolts etc can be in an old ice cream container,larger things of course will need a bigger container,most farm/horse supply places have a bulk container of it,you take your own 5/10 or 20 litre container and theyll fill it,it only costs a few dollars and can be used over and again,the smell makes you want to open a beer though!DO NOT place any alloy items into it though!it wont hurt chrome or paint,alloy stuff will mottle and disapear!

[Ksgfx]

Welcome to the fun world of bike restoration. I have recently started doing this myself and am currently starting my 5th bike. I'm also a new restorer without a lot of shop space so here is what I've learned.

- Get a bench grinder with some wire wheels. I use this all the time to remove rust and paint. Especially helpful in cleaning up bolts. You can also get some polishing wheels to help with shining things up.
- For larger items I use wire wheel attachments on my drill, as others mentioned you will need to sand it down afterwards to remove scratches.
- Evaporust is really good for chemical removal of light to medium rust. I've seen it make a part look new within 24 hours.
- Chrome takes a lot more care to clean-up. If it's surface rust then I try Evaporust first, and then follow with very light scrubbing with #0000 steel wool and WD40. It is very important to go easy as this will create micro scratches that will need to be polished out later. Unfortunately if it is pitted or flaking off there is not much you can do.
- For the engine and other aluminum parts I use Scotchbright and WD40 to create that satin look. You can find different levels of Scotchbright which will help create a finer shine. You can also move to polishing after you get the oxidation out of the metal.
- I use VHT Chassis and Roll Bar Paint to repaint or touch up all of the black parts. It does take a long time to cure, but once it does it will hold up to minor bumps and bruises.
- Finally I'm sure you will find a few parts that are beyond saving. I recommend asking the group here first to see if anyone has one you can buy before moving on to Ebay which will always be more expensive.

Good luck and happy restoring.

kev

[Don R]

 Aluminum foil and turtle wax chrome polish are my favorites on chrome. For aluminum, fine sandpaper, and a scotchbrite flap wheel does wonders, an old blower motor with an arbor on it will spin cheap buffing wheels. There are different grades of rouge identified by color.
 Go slow and if in doubt ask us. I learned the hard way about taking things apart. If you do it too soon or lose track of parts they don't always go back together.
  My #1 rule is make it run first so you know what you have. That's not always possible though. #2 rule is have fun doing it.

[dmfernandez87]

So i spent a good part of the day degreasing and cleaning the hell out of the frame, swing arm, and center stand. Removed the steering bearing out of the triple tree too, which was a pain in the ass for the lower in race.

Been tackling the frame and sanding down the rusty parts with an 80 grit sand paper, will go at it more today. After I’ve sanded the main rust areas, do I now:

1. Apply rust reformer to areas that still contain rust ?
2. Spray on the exposed metal portions with self etching primer?
3. Spray the entire motorcycle in a black paint. Im guessing it’s ok to spray over the old paint?

Also in a turn of events, my neighbor wants to powder coat his truck tool box and has a friend that does powder coating. Says he can give me a deal to blast and coat everything, so this maybe all for nothing lol I’ll find out tomorrow how much he’ll charge. What would be the other components to toss in the mix for powder coating if I get a good deal ? Rims?

How do I handle the threads on the frame ? Tap and die ? Prep before powder coating ?

[timtune]

For this I would just rattle can paint. Powder coating in the wrong place is very hard to remove - almost impossible without wrecking the under lying surface.
Plus it's cheap and cheerful.

[Alan F.]

Evaporust is a good one to remove rust only without harming paint or any other plating. But things will rust again if unprotected. CorrosionX is a thin film corrosion inhibitor that even has a US Navy part number.

I'm using these two products only on my CB160.

[Stev-o]

I vote for powder coat every time. A dremel tool can easily remove the finish if necessary.

[BenelliSEI]

Include side stand and centre stand for powder coat. I’ve never done rims, but if yours won’t cleanup, it’s an option. Most powder coaters will seal up any holes with foil tape and plugs they have for the job. Check and make sure. I keep a tin of old bolts I screw into holes, that have been coated a few times.

If you have knocked out the headstock bearing races, make sure that whole tube gets taped off! It’s a bugger to clean out afterwards.