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I'm contemplating painting the cylinder head covers (and engine crash bars)on my 91 GS but am unsure as to best do this to insure both a fairly decent job (need not be perfect) and one that lasts a while. The covers will require some sanding of scrapes, etc. I'll be doing this with a rattle can. Any tips as to type/brand of paint, sheen, prep sanding, etc. Thanks, Reinhard

Tremclad semi gloss black. Surface preparation is the key to a good job.

Some larger Napa Auto Parts stores have Martin Senour products in rattle cans. This is real automotive paint.

ColoRite has real stuff in rattle cans, and they specialize in motorcycle paints. http://www.colorrite.com/

Eastwood has TONS of such products. http://www.eastwood.com/

As with all painting, proper prep and priming is the key.

As mentioned I will sand down the roughed up/scratched areas and I'm assuming that I don't need to go to bare metal on the entire cover but just roughing up the existing surfaces with some fine sandpaper will be sufficient prep. Is that correct? Also, do I need a coating of primer paint of some sort prior to the black paint and if so, need this be a high-temp primer? The finished product should look good but doesn't have to be perfect. I'm more concerned with the paint peeling/flaking due to incorrect paint (is some form of engine enamel best?) and the higher temps on the covers. Thanks

I had great luck with "Dupli-color high heat with ceramic" that I purchased from Napa, part no. DH 1602 high heat black.

Roughready wrote:As mentioned I will sand down the roughed up/scratched areas and I'm assuming that I don't need to go to bare metal on the entire cover but just roughing up the existing surfaces with some fine sandpaper will be sufficient prep. Is that correct? Also, do I need a coating of primer paint of some sort prior to the black paint and if so, need this be a high-temp primer? The finished product should look good but doesn't have to be perfect. I'm more concerned with the paint peeling/flaking due to incorrect paint (is some form of engine enamel best?) and the higher temps on the covers. Thanks

What surface prep is required varies with every product. Most need primer over bare metal, but many engine paints do not. Some need a sealing primer between them and the old paint, some do not. This can be either for adhesion, or for compatibility between finishes. Your "roughed up/scratched areas" may have gouges deep enough that you need some filler or high-build primer to smooth them out.

The valve covers don't get super hot, but some type of paint designed for engines would certainly be wise. Such paints are usually oil and fuel resistant as well.

Depending on the overall condition of the valve covers.........
I would firstly remove the studs from the covers by using two nuts on each stud and locking the nuts together, allowing you to use the inner nut to screw the stud out.
Then using wet and dry paper on a piece of glass or similarly flat surface, rub the cover in a circular motion to ensure the sealing surface of the cover is not warped or scratched.
Then I would use a flat file to dress the fins, resulting in nice looking consistent width fins. You can roll the file around the curved part of the fins to good effect. Having the studs removed helps to do this.
File/sand shallow scratches/dents. Deep scratches and dents are best cleaned out with an appropriate tool before being filled with JB weld or similar and then filed and sanded.
I have used ordinary low sheen quick dry black enamel with good results. You will get stone chips and sand blasting from normal riding so there's not much point going overboard with the paint imo.
Every so often when I do my valve clearances, I give the covers a clean and another lick o' paint.
I paint the entire outside of the cover and when the paint is dry, I take to it again with the file to remove the paint from the top of the fins. Bewdiful!

Powder coating would be the best finish I 'spose as GSPD has done with his covers. The same prep work is required and the fins can be filed in the same way to highlight.
I think high temp engine paints need to reach a certain high temp in order to 'set' the paint?

ME 109 wrote:Powder coating would be the best finish I 'spose as GSPD has done with his covers. The same prep work is required and the fins can be filed in the same way to highlight.

Powder coat is the toughest, but not as easy to touch up as paint.

ME 109 wrote:I think high temp engine paints need to reach a certain high temp in order to 'set' the paint?

Most of the rattle can ones I know of are, but valve covers are a really easy thing to stick in the oven.

but valve covers are a really easy thing to stick in the oven.

I can see it now. "What are you cooking dear"? Er, fins and chips!

Major Softie wrote: Powder coat is the toughest, but not as easy to touch up as paint.

My experiences with powder-coated surfaces have been very different than the Major's.
I have found that powder is no tougher than a similar formulation of paint.
i.e. – epoxy powder is no tougher than epoxy paint ... and visa versa.
Each will be just as "tough" and enduring as (thorough) prep work and (proper) application will allow.

When all is said and done, the solvents evaporated or thermosetting complete –
the resulting colored surface of paint or powder that remains is very much the same.


Nor do I find powder difficult to grind, file, sand, or feather, and powder can easily be "touched up" with paint.
The only difficulty might be an exact color match –
unless you are mixing your own paint to match or have chosen a color of powder that is easily matched.