best way to run external oil return lines?

[Mother]

 tips?  warnings?

[Hillside Motorcycle]

Drill/tap/spotface for 1/8 NPT, below bottom of the spring pads on the ex valves.
On a T/C drill/tap/spot cases below cyl spigots for same thread, and connect with a line of choice.
On older bikes ie Shovels we'd pull the oil from the head to the fitting on the pump that would normally evacuate the primary, that way no excess oil in the cases.
Scott

[1FSTRK]

TC engines return upperend oil to the cam chest, would think drilling and returning to the flywheel compartment below the spigots would be a step backward in the sumping department.

[Mother]

 What about running lines from the heads back to the oil filler/ oil pan?    our maybe the cam chest?

[1FSTRK]

Back to the cam chest would allow oil and engine pressures to work the same as the factory designed.

[1FSTRK]

Did you plug the stock return passages?

[Mother]

 Not yet,  but the head porter wants to  do it so he can bring the port out a lil bit. I like the idea of returning the oil to the cam chest.

[1FSTRK]

If you are careful you could drill and tap the the base of the cylinder just above the base gasket surface and hit the original drain hole at its base. This would let you come out of the heads any where you want and put the oil right back in the original passage at the bottom of the cylinder to enter the cam chest through the cases. Saves drilling on the assembled lowerend. Just plug the old holes in the head and gives you the external lines. .

[Hillside Motorcycle]

What about running lines from the heads back to the oil filler/ oil pan?    our maybe the cam chest?

Don't you have an S&S crank case?
They drain the f/cyl right into the crankcase.
Scott

[Mother]

 Scott I'm using my factory cases...... does the cam chest  pull vacuum?

[rbabos]

Scott I'm using my factory cases...... does the cam chest  pull vacuum?

Vacuum , pressure pulses are the same in the cam chest as in the case. Pushrod tubes and stock return down the cyls balance the pressures all around the engine cavities. Unless I'm missing something here, I'd drain the heads into the pan, which reduces the amount of scavanging needed from the pump since the heads are no longer dumping the oil into the cam chest. Not an option with internal lines.
Ron

[Mother]

Well we talked it over and with the intake taking longer(and the transmission) I am going skip the external return lines on the 124 for this season

[No Cents]

Mother...did you ever look at the T/C 131 motor on R&R Cycles web site...it has external oil lines on it.
Randy would know the skinny on them.

[hrdtail78]

You can't drain through his iron cylinders.  Base bolts and head bolts setup.

[No Cents]

just an example (picture) of how R&R does it...maybe using the same technique to route external lines?

[Mother]

 Randy@ Hyperformance said to run the return lines to the camchest.  if the final flow numbers are not where we want them then I will go with a 1.700"  exhaust valve and external return lines to allow more port work.

[No Cents]

 
good plan...I like the way Reggie routed the lines on their 131"er. I noticed the rear head went back to the cam chest...but it looked like the front head tapped back into the case.
I'm sure Randy wouldn't steer you wrong...he is one smart man!

[Mother]

will have the final flow numbers in a day or two and will decide then....I could possibly be ready to light her up this weekend or early next week

[No Cents]

will have the final flow numbers in a day or two and will decide then....I could possibly be ready to light her up this weekend or early next week

Rock On !