Boxerworks.com

Recently I noticed a small leak of air (in time with the revs) coming from the front of the right side cylinder. Its coming out between the rocker cover and the cylinder head (see photo).
Am I right in assuming this would be fixed with a new rocker gasket? Or is there something more serious wrong?

A new gasket might fix it, or it may need a small amount of silicone sealant. If you can get the gasket off in one piece, you may be able to use silicone on it.
Strange place for a leak. It's no big deal at all.

I often used 2 gaskets when trying to fix an oil leak. It was successful, but air is less viscous than oil...

Thanks for the reply guys. I figured it was probably nothing major. I'll take it apart and replace the gasket and see how i go!

Mine did that so I took the rocker cover off, removed the studs and used some fine wet/dry paper on a piece of glass to true up the sealing surface of the cover, then installed a new gasket. Use a magic marker to paint the sealing surface before you start then you will see if its warped when you start the process.
Use a figure 8 motion when on the wet/dry paper. Use water to keep the paper clean as you work.

I have seen cases where one or the other surface isn't flat. The head is hard to flatten, but the valve cover is easy, as mentioned by PAS.

In every case it is easier to seal than flatten. You decide how you wish to solve the leak.

PAS wrote:Mine did that so I took the rocker cover off, removed the studs and used some fine wet/dry paper on a piece of glass to true up the sealing surface of the cover, then installed a new gasket. Use a magic marker to paint the sealing surface before you start then you will see if its warped when you start the process.
Use a figure 8 motion when on the wet/dry paper. Use water to keep the paper clean as you work.

PAS gets my vote as well. I've used that technique effectively. Probably everybody has figured it out for themselves but the studs in the valve cover can be easily removed by double nutting them. Also I will often use a sandpaper other than wet or dry carborundum. If you can find it, especially in a fine enough grit, aluminum oxide sandpaper on a cloth back (think broken belt sander belts) will work well, at least to get the roughing 'cuts' done. Then follow with finer wet or dry sandpaper, wetted with a bit of dish washing soap in the water.

Ken

I trued up a pair of Subaru cylinder heads with 320-grit paper contact-cemented to a thick piece of glass lubed with WD-40. Followed the 320 with 400-grit, and checked my work with a Starrett straight edge & feeler gauges. It worked great, and still seems to.

I think the head is more often the problem than the cover. But at least the cover can be easily checked and surfaced.
If you've just done a nice resurfacing job and it still leaks, silicone on the head side of the gasket only is sufficient.

Lets not forget Real Gasket http://www.realgaskets.com/files/motorcycle.htm
the silicon valve cover gasket. They even come in black, now! (probably not as good...)