Best rockerbox gasket? I have 3 to chose from....

[1340evo]

So it looks like the bloke who owned the bike before had some kind of fetish for rocker box gaskets? In what came with the bike were 3 new sets, so which is the best?

The ones I took off are the big one piece James gaskets that have a bead on both sides.. and I got to say they didn't leak...

But the 3 I have new are :-

James, steel with bead on one side, but individual type

Interface solutions are the blue ones with a bead on one side

and S&Sgrey ones, just plain but have 90-4058 & 9 on them


Or none of the above and get something else... ?

I have the copy S&S billet rocker boxes and got to say they are not flat when sat on top, but guess they will pull down when nipped up?

Anyone any advice on this

[jsachs1]

I use the 1 piece metal ones from Cometic. Similar to the ones I use on Twin Cams.
John

[1340evo]

Not right common in the UK...

If you had to use one of these which way would you go ??

[kd]

I won't choose your gaskets for you but I will comment on the rocker boxes not sitting flat.  I have had to change leakers because of that.  The rocker and cover fasteners are not oversized and screw into aluminum.  That will give you an idea how much pulling down and straightening will be possible.  If they aren't Chrome you may be able to block them true enough on a plate to ensure they seal.  I expect the collection of rocker gaskets is a clue to the previous owner fighting with them. I see no other reason when investing in gaskets in quantity if you have no need to.

[1340evo]

They are actually dished in the middle so rock in all directions. I've measured it at .005" but you can actually pull them down by hand by clamping your fingers onto the fins.
If I can do that then think they will be okay... But, could always put them on their tops and press a bock into them to get them better.... Just don't want them to dish the other way

None of the gaskets have been fitted before.. I'm thinking the James TBH

[1340evo]

Have put them down to 15 LBF without a gasket and gone around them with a .0015 fealer gauge and I can't get it in anywhere.
Could they be designed to like this to put additional pressure on the inner sealing ring?

[1340evo]

I did manage to push them back a bit so will see what happens. looks like loads of compression on the big O ring in there so would be suprised if that leaked....

[Reddog74usa]

Have seen the middle plate warped on evo's. Never had an issue with the factory gaskets from the dealer.