Searched all over, 97 WG with 19, 800 miles. New S&S 508 cam, new bearing, S&S reed valve. Runs great, I did a wide open up to 100 mph blast to check plugs, spewed a bunch of oil. Took rocker covers off to replace umbrella valves, I did put Feuling hp plus lifters in and they supposedly pump more oil into the top end. Cannot find any info on drilling the drain hole out. Lots of post about TCs, What size should I drill the tiny hole out that drains into the bottom section of the rocker box. Thank You

 

Running too much oil? Spec is often too much for higher rpm operation. If you keep running it (and cleaning), it should find a level it likes.

 

Hillside posted this on Facebook a while back. I have no idea if it’s a legit thing, I haven’t tried it.

 

Recently drilled mine on my 97 WG.

 

That is a twin cam rocker assembly, not an Evo...
I don't know of anything to drill in an Evo..

 

I read to drill the drain holes to 1/8”-3/16”. I took mine to 1/8” and touched it up with a counter sink bit. Tried the Cometic umbrella valves and they just didn’t fit snug at all. Local HD shop had OEM and white silicone upper rocker box gaskets, the OEM umbrella valves fit nice and snug, did have one top pushrod O-ring pinched a little so it was replaced. Problems solved, I am getting a catch can and taking the vent lines out of the intake. Thanks for all the advice and suggestions. Real happy with the S&S 508 cam, quiet valve train, runs good. Happy Easter everyone.

 

From the book "101 Harley-Davidson Evolution Performance Projects" by Kip Woodring and Kenna Love:

 

Yup that is the book I picked up, found a copy at a local used book store. Good stuff in side those pages.Thank you

 

Didn't know about that.. Never had an issue or the need to drill it.. Even with an S&S HVHP oil pump..

 

Ditto on never needing to drill the channel,since the problem most of the time, is the after market umbrella valves don't seal correctly to begin with.
The other one is the after market O rings for the middle and top not being thick enough, and causing leakages as well.

So I like the JG and other after market bottom gaskets between the rocker cover on top the heads over the steel HD one, but come rubber O rings and umbrella valves, HD all the way.

Plus, let face it, only the EPA wants you to dump the oil out of the breathers back into the intake manifold, so kind of step 1 to stop that in the first place, so you not just burning more oil in the cylinder to begin with. Step two is fuel is cooling, so richening up the mixure over the lean condition epa wants that can burn the motor up, kind of needed as well. Hence some of the Harleys are leaving the factory at an ARF of over 18, and not 14.7 where they should be at instead.

And remember, not a single evo left the factory with cats on it, so not a motor that you need to be so PC on in the first place.

The other one, easy to fight a noise ticket for mufflers, when the bike came with OEM screaming eagle mufflers to start with.
Hence they can sound test all they want, but when you show them the OEM Harley labels on the mufflers,and point out that the bike came stock with them at the time of build that year and where legal, they have no legal leg to stand on to write you a ticket in the first place.
Better yet, on the ticket if they want to push it and write you a ticket, just write on the ticket before signing it, that Office was shown OEM Harley labels on mufflers proving muffler where legal at build when factory installed.