oil feed lines into valve cover

anyone know if the valve cove is above or below atmosphere pressure at high rpms? Or if it changes at all??? I'd like to put oil feed lines to keep my cams nice and oiled at sustained high rmps.......anyone done this yet? Oil will trickle down with gravity? Any thoughts??

 

my thought is that the Yamaha engineers made sure the cam wasn't going to run dry and you probably don't need to worry, let alone make a mod that might affect oil pressure elsewhere in the motor and cause a BIG issue...

 

In racing seca maxim motor very common point of failure is the cams due to the high rpms temp rises oil thins cams fail ( especially the 1100s motors for some reason ) given I run spin on oil filter ( more oil cap ) I have an overflow container from my crank case vent, which at high constant rpms pushes oil out and into res..(which is vented) the res drains back intothe crank after rpms drop ( pressure falls ) my thoughts are to have it drain over the cams instead of into a res?
Any thoughts??

 

what we do on some quads is to use carb jets. the hot thin oil sprays enough to mantain lubrication but not too much to drop pressure, or fill the topend with oil. you can change jet size to adjust the flow.

how were you going to design the spraybar ?

i think it would be a worth while mod, but could also be fatal to the engine if proper care and attention to detail isnt taken.

 

yeah its gonna be some engineering before im gonna make it happen trying to do the research now.....like i said i don't think that the valve cover is under pressure, but gravity fed spray bar wouldn't push enough oil i don't think.......depends on the rate that the valves drain down too....hmmmm

 

The valve cover should be the same pressure as the crankcase due to the wide open cavity that the cam chain goes through!

 

The cam bearings get a high pressure oil feed, I'm sure. So if you rigged something up, you would just tap into that oil galley in the head.

Before you do that, why don't you run the bike for 2 SEC at 7,000 RPM with the valve cover off, and see how much, or how little oil gets squirted all over.
I expect you'll be impressed how much squirts out of the cam bearings.

Plan on a mess. It's just oil.

 

just me thinking aloud.... run an external feed line, into a "manifold" on the valve cover that has size 75 (???) carb jet aiming at each cam lobe. you want the oil to hit the cam right above the lifter on the forward facing side.

it would be a pain in the butt to do, but if you paired 2 jets per manifold and made 4 manifolds (one for each leg of the H-shaped cover) and plumbed them all to a common supply line, it would work perfectly.

you might need to experiment with the jet sizes, and figure out what pressure the bike is running the oil at to see what will give you just enough flow, and "spray" to lube the lobes without causing the pressure drop.

do these engines have piston coolers? if not while you are at it you could install them too!

 

i have seen this mod on a xs1100 motor which is pretty much the same plumbing ( i mean different stroke piston size etc.....) but oil plumbing should be close to the same.........i agree that the cam chain is im the same cavity but i don't think its under the same pressure as the crank case ( near the vent ) i don't know.....hahhaa don't think i really want to run with the valve cover off...oil clean up is never fun....
more research is needed....

 

You don't need it!
The Cam Galleries fill-up with oil while the bike is running.

The problem some models (V-Max, Radian, early Ventures) had with worn-out Cam Lobes was due to the way they made the Cams ... not them not getting oiled right.