View Full Version : Inreasing Top End Oil Flow

03-08-2003, 11:55 PM
In an attempt to increase oil flow to my '74' Period Drag Bike Sportsters 'Top End', I am considering increasing the I.D. of the upper oiling lines, top/lower fittings I.D. holes and crankcase/rocker box fitting oil passage holes inclusive. By doing this will I increase the flow but at the risk of lowering the pressure to the rocker arms? Or will both pressure and flow increase? Also is there any way to effectively increase pressure from the stock pump? I run straight 50/60 WT Castrol Motorcycle Racing oils thru a remote spin on type 'Fram' filter. Any thoughts?....:cool: ..Hrdly-Dangrs

61 panman
03-09-2003, 08:54 PM
I am no oiling expert however I have had my ear tuned to many oiling discussions as I see proper oiling as the best way to increase engine longetivity. Most knowledgeable people I have listened to consider many motorcycle top ends to be over oiled.
If you look in JIMS catalog they sell race application only rocker shafts with a grease fitting on the end and the product description says "designed for race bikes using a dry top end".
You said drag bike. Are you going to race this bike in the 1/4 mile or just rip snort creating havoc all over town.
Last months Wallnecks had a similar story to your Englishtown over the top backwards tale. The bike magazine editor ( I can't remember which mag) was testing a '72 sporty at the track and wheelied it over backwards just out of the gate, in front of all his buddies. It was capured in pictures, I am sure he never lived that one down.
Just my thoughts,

03-09-2003, 11:39 PM
Hey Doug, how's it going. Since the amount of travel the oil must go to get to the top end and what with the early style oil pumps on the Sportster being what they are and located way down under the motor, and the added stress and revs that this motor will be put under I'm looking to hedge my bets and keep sufficient oil supply to the rocker arms. Basically looking for some experienced advise as to this modification. This Sportster will be Set-Up to it's 'Year of Manufacture' in Original Parts and known Period Modifications. Yeah, just like the 'Bobbers' Class we've been B/S'ing about!. But in this case its for the 'Competition Class'. I was around the Motorcycle Scene back then, so if someone was to tell me that a particular part or mod is incorrect, I can look him straight in the eyes and say 'BULL***T with Authority!! Ha! Anyway, it's an excercise in all 'Old School' Performance Mods. Using lot's of learned 'Go Fast' secrets. Yes the bike is being set-up for real 1/4 mile racing and yes I have done stop light to stop light fine tuning. Just playing with different gear ratios, jets and stuff. Right now the bike runs total loss electrics, no generator, and fully lightened valve train. A Joe Hunt magneto is in the works. I'm looking into modifying it so I can bolt it on where the generator would normally go. I've modified the primary to an open type and continue to refine it. My goal is gaining all the useable HP available thru realistic and affordable mods and weight reduction, (the bike and me!) Oh yeah, that Sportster I talked about was a beauty. Basically a Street Bike that you could tell the kid put a lot of work into. Unfortunately, he didn't take into account the rubber to rubber contact of his rear tire and all that rubber laid down on the track from all the many previous racers tires. Pure Traction! No tire slippage there! I certainly learned a lesson thru him! And it didn't cost me a cent! The best kind!!...:)..Hrdly-Dangrs

61 panman
03-13-2003, 09:54 PM
This is not one with experience with this operation replying but if you put the generator back on maybe you could run an electric pump,
thats the best I could do,

03-14-2003, 05:09 PM
Hey Doug, that last tip of yours is worse then the one I gave you about chain adjustment (Fat Brother In-law)!...:D ...Hrdly-Dangrs

61 panman
03-15-2003, 08:20 PM
Yeah what goes around comes around I guess Have a great St. Paddies day, it is the only day of the year I am Irish,