This is an old revision of the document!
REF: Oiling & Lubrication - Sub-22P
1977-Present Gerotor Oil Pump Capacities
The charts below are based on testing done by Hippysmack of the XLFORUM 1)
Overall oil pump volume was calculated by measuring the volume of one tooth cavity in used oil pumps and calculating volume against RPM.
The figures take into account that the oil pump turns 1/2 the speed of the engine.
Click Here for the full testing and procedure in the Sportsterpedia.
NOTE: The figures in the chart represent 100% pump efficiency and DO NOT take into account any amount of internal pump leakage.
Internal leakage (or slippage) is an inherent condition of these pumps and WILL affect total volume output.
Real world GPM will be lower than what is listed below.
| 1977-1985 Sportster Oil Pump Volume in (US) Gallons per Minute (GPM) | |||||||||||
| Year Model Oil Pump → | 1977-1985 | 1986-1990 | 1991-1997 | 1998-2006 | 2007-Present | Oil Pump RPM ↓ |
|||||
| Engine RPM ↓ | Feed Gears | Return Gears | Feed Gears | Return Gears | Feed Gears | Return Gears | Feed Gears | Return Gears | Feed Gears | Return Gears |
|
| 1000 | .121 | .346 | .185 | .346 | .185 | .346 | .185 | .485 | 500 | ||
| 1500 | .182 | .519 | .277 | .519 | .277 | .519 | .277 | .727 | 750 | ||
| 2000 | .242 | .692 | .370 | .692 | .370 | .692 | .370 | .970 | 1000 | ||
| 2500 | .303 | .866 | .462 | .866 | .462 | .866 | .462 | 1.212 | 1250 | ||
| 3000 | .364 | 1.039 | .555 | 1.039 | .555 | 1.039 | .555 | 1.454 | 1500 | ||
| 3500 | .424 | 1.212 | .647 | 1.212 | .647 | 1.212 | .647 | 1.697 | 1750 | ||
| 4000 | .485 | 1.385 | .740 | 1.385 | .740 | 1.385 | .740 | 1.940 | 2000 | ||
| 4500 | .545 | 1.558 | .832 | 1.558 | .832 | 1.558 | .832 | 2.182 | 2250 | ||
| 5000 | .606 | 1.732 | .925 | 1.732 | .925 | 1.732 | .925 | 2.424 | 2500 | ||
| 5500 | .667 | 1.905 | 1.017 | 1.905 | 1.017 | 1.905 | 1.017 | 2.667 | 2750 | ||
| 6000 | .727 | 2.078 | 1.110 | 2.078 | 1.110 | 2.078 | 1.110 | 2.909 | 3000 | ||
| 6500 | .788 | 2.251 | 1.202 | 2.251 | 1.202 | 2.251 | 1.202 | 3.152 | 3250 | ||
| 7000 | .845 | 2.424 | 1.294 | 2.424 | 1.294 | 2.424 | 1.294 | 3.394 | 3500 | ||
| 7500 | .909 | 2.597 | 1.387 | 2.597 | 1.387 | 2.597 | 1.387 | 3.636 | 3750 | ||
