There are 2 ways to go....

1 • There is a silver (basically) a silicone gasket make sold through motorcycle shops (and probably on Amazon) that goes under various names... "HondaBond", "YamaBond" and other "xxxBond" names. (This may be the same as Hylomar.) Being silicone based, it is important that both surfaces be absolutely oil-free. I highly recommend using a clean rag soaked in rubbing alcohol or lacquer thinner. (Sometimes Brake Cleaner or Carb Cleaner cut the oil, but leave trace amounts of other thinners that keep the sealer from fully setting.) Use of compressed air is almost mandatory.

The catch to using this stuff is that everything must be ready to go. Once it's applied, you must assemble in the next 2 minutes. You won't have time to fish around for the ring compressor in your tool box. If your tools aren't behaving, then you'll need to start all over again. And this stuff will fight you to come back off.

Which leads to the last and final part.... I hate this stuff, mainly because I always get the bike that someone else tried to fix, which is sealed with this stuff. The sealer is tenacious and won't turn loose of anything. And of course, there's always too much. I have often spent more time removing this sealer than I did doing the repair. Airhead cylinders can be especially hard to break loose and remove because they are so delicate and have no pry points.

2 • Another way to go is with the series of "gasket makers" from LocTite. There are several of these #510, #515, and another #428. (This is also sold at Dodge/ Chrysler dealers as Mopar #4318083.) The different numbers refer to ability to seal different thickness gaps, but for this application of finely machined surfaces they are all equal. These products are a pink to red colored, form-in-place, anaerobic gasket maker that have 2 very endearing qualities. a) Being anaerobic, they don't start 'setting' until the two parts are in place and bolted together. That means you can apply them 30 minutes before assembly. If you assemble, and need to immediately pull things back apart, it's OK. No need to stop, re-clean every part, and re-apply sealer. If it's still moist, then it's still going to seal.

b) The second wonderful quality is that surfaces don't need to be surgically clean in order for this sealant to work. This makes it perfect for sealing places like the threads of the oil pressure switch where it's impossible to clean up inside the engine recess. Oil drain plugs are another. It's great to apply instead of replacing the metal washer every time. This sealant doesn't seem to be bothered by grease or engine oil. Of course, we clean as best we can, but the mating surfaces no longer need to be "absolutely clean" as with the silicone-based products.

• Other endearing qualities include very easy clean up. Any excess that squeezes out of the joint is merely wiped away. It doesn't develop a "grip" on the metal until it cures. And it is also an excellent additive for questionable gaskets. I simply squirt it onto my fingers and rub it onto both sides of un-treated paper gaskets to help them seal. It's really excellent in this role.

Hope this helps.

Thanks I will look in to the LocTite products. I'm sure they will have that everywhere up here. Cheers TC

If you haven't already done this job, take a look in Tech Tips. The very first item under engine T-11, is an article on cylinder base sealants. Its quite good and I have used these same sealants under different names for years. Currently I can get Yamabond here in our small Berg so I use it!.
It is the only sealant that will keep the oil in the primary chaincase in my '62 Goldie.
M

I have done this on my 80, r100t about 15 years ago but there were some differences in the seals. The Local Guru (RIP Georg Rahn) advised agains using a sealant on that model and it held for 20 k km when I sold it. to my knowledge it still is holding up. I will def look at the write up thanks TC

grainger anchorage should have hylomarand loctite 518 is used up there in the oil industry