Tappet Covers: Gaskets or O Rings?

Downeaster

Downeaster

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Did a little valve train tuneup on the bike today, and noticed that three of my four tappet covers are weeping a little oil. The o-rings are pretty flat on the head side, I'm guessing they're the original rings.

I see MikesXS has either gaskets or o-rings and states that the gaskets will fit any bike. Prices are about a tossup.

Any preferences as to which to use?

I'm leaning towards the gaskets as they have a greater sealing surface.
 
I actually used both, lol. But if I had a choice it would be the gaskets. The O-rings allow you to open the tappet covers without having the gasket stick to the head, but even with new O-rings I noticed a little seepage.
Just my thoughts
 
Pop the o-rings out and flip them over. That will present a fresh, round side facing out for better sealing. That's all I did with my originals which were flat like yours, and they've been sealing fine for the past 6 seasons. On the 3 hole covers, you can install them in one of 3 different positions 120° apart. For some reason, they seal better in some positions than others. Experiment a little to find the right position.
 
5twins said:
Pop the o-rings out and flip them over. That will present a fresh, round side facing out for better sealing. That's all I did with my originals which were flat like yours, and they've been sealing fine for the past 6 seasons. On the 3 hole covers, you can install them in one of 3 different positions 120° apart. For some reason, they seal better in some positions than others. Experiment a little to find the right position.
Click to expand...

That makes sense. I'll do that tomorrow.

Putting together a shopping list for this winter's bike tweaking projects. So far I've come up with:

A 32 tooth rear sprocket

Brass washers for when I re-torque the head

New rear shocks

New rear foot pegs (mine sag and also interfere with the new mufflers)

Maybe send the tin out for a little bump and paint (depending on what I get for quotes)

Do the Minton Mods on the forks

Buff out the tappet covers

Check the carb mount rubbers and see if they need replacing
 
I haven't tried the minton mods on the forks but the emulators work great. They take the road shock out of the bars and are adjustable. The best thing I did on my bike.
 
On tappet covers inspect the flat surface next to the O rings. I find blobs from clear coating on about every bike i do. Carefully razor blade them off. That and flip the o-rings like 5t sez. A little hook made from the stainless strip from a windshield wiper blade helps get them out without tearing them. I prefer the neater look of the o-rings. Others have reported a low cost source for new o-rings. Can't recall what it is at the moment.
sstools.jpg
 
Correct me if I'm wrong, but isn't there both version's,,,flat or o-ring style. So wouldn't you need to use the correct method of sealing. :confused:
 
Yes and no. You can't use O rings on the covers that don't have the groove machined for them, but you CAN use gaskets on O ring covers (without the O ring).
 
Scrambled said:
Looks like a collection of them. I bet Gary even has tools made out of flint .
Click to expand...

Save the stainless strips the next time you replace a windshield wiper. The stainless is VERY stiff, machines and holds an edge very well. Yes I have about 10 little tools I have made from the strips. One of them has successfully removed idle mixture screws with completely ruined screw driver slots. One removes float bowl gaskets without tearing them. I think the "shiv" was to remove the little bits of float bowl gasket stuck to the carb body without wrecking that little ridge.
 
5twins said:
Pop the o-rings out and flip them over. That will present a fresh, round side facing out for better sealing. That's all I did with my originals which were flat like yours, and they've been sealing fine for the past 6 seasons. On the 3 hole covers, you can install them in one of 3 different positions 120° apart. For some reason, they seal better in some positions than others. Experiment a little to find the right position.
Click to expand...

Digging back a few years with this one, but do you have any recommendations for getting a better seal with the O rings other than trying to rotate to different positions? Ive tried that, cleaning the entire area for smooth contact, flipping the O ring, and even installed a new one (even though the leaking one was basically new already). I cant seem to get rid of this small oil leak that recently started!
 
The original diameter size is a rather odd 2.8mm, difficult to find, but the more common and readily available 3mm diameter ring fits just fine and seals nicely.

M0PkYiR.gif
 
Kubes42 said:
Digging back a few years with this one, but do you have any recommendations for getting a better seal with the O rings other than trying to rotate to different positions? Ive tried that, cleaning the entire area for smooth contact, flipping the O ring, and even installed a new one (even though the leaking one was basically new already). I cant seem to get rid of this small oil leak that recently started!
Click to expand...

Jan_P .s .. Department of Dirty Low down tricks ..
I once needed a O -ring ..standing on my knees working a ring I did not have
I did have a slop " Liquid Gasket " Plastic Padding
Used it many times after that

it is in wrong language but that was the one

https://www.hjertmans.se/produkter/...MI3bjHtLCp7wIVVLvVCh2aGg3tEAQYBCABEgIWsvD_BwE

I smeared that red slop liberally on both sides of the old o-Ring . put it back in place
Worked amazingly well and I have had a friend that could not seal a difficult Water Leaking Cadillac
That stuff did the trick.
 

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