Baker Plus-One Oil Pan - Add An Extra Quart Of Cool

Baker Drivetrain understands that nobody changes a motorcycle oil pan for purely aesthetic reasons. That's why they designed their Baker Plus-One Oil Pan (+1P, MSRP: starting at $399) to not only look great but also to add some key functional features like improved oil cooling and a built in stabilizer boss. The Plus-One fits 1993-2008 Harley-Davidson FL motorcycles.

The reduced engine oil temperature (Baker claims 10 degrees on an 80 degree day) is achieved by enlarging the pan capacity to add an extra quart of oil, by moving the hot oil return port to the rear of the pan (the stock pan has the oil return and oil pick up both near the front), by using multiple internal aluminum baffles to eliminate the stock plastic baffle, and by adding cooling fins on the bottom of the pan.

Plus, to keep from hiding their oil pan under a wide, stabilizer trans plate, Baker added a structurally located, integral boss for the Alloy Art TXR stabilizer. That makes adding the TXR a snap, which we'll cover in a later issue.

Oh, and that aesthetic thing, the Plus-One comes in two attractive styles; either a one-piece cast aluminum pan in black or natural finishes that will match your stock motor or a two-piece billet aluminum pan in chrome or polished finishes that will add some light where the sun don't shine. We were happy to install the two-piece polished pan on our 2007 Road King Custom.

The Baker oil pan installation instructions, as well as the factory service manual, call for removing the rear wheel and the swingarm pivot shaft, then raising the transmission about an inch above the frame crossmember for clearance of the oil pan. However, we don't like to remove any unnecessary stuff, so we tried a different technique to save time. We raised the rear of the bike about a foot and rested the rear wheel on a wheel ramp. Then we compressed the rear shocks and held them with a tie-down strap. Effectively, this is pushing down on the rear frame struts, which then pushed the lower frame down and away from the rear tire and created a sufficient gap to slide the stock oil pan out and the new Baker pan in. This also gave us room to work under the bike. It was a close fit but certainly a lot less work than removing the rear wheel and pivot shaft. Of course, this trick may not work with your model.

To determine the temperature reducing performance of the Plus-One, we used two different temperature measurement techniques to compare before and after values. With the stock pan we rode the bike to get the engine up to normal operating temperature. Then we noted the Engine Temperature (ET) in the log from our Daytona Twin Tec TCFI engine module and we measured the external engine temperatures in two places with our infrared thermometer. After installing the Baker oil pan, we again rode the bike and re-measured. All temperatures are in degrees Fahrenheit. The results are shown in the following table.

As you can see, the Plus-One oil pan brought the temperature down a few degrees, but on our runs, not the 10 degrees claimed by Baker. However, we should note that it's difficult to compare oil temperatures. The infrared thermometer doesn't read shiny surfaces very well so we got some variations on the polished pan. With the log data, we tried to pick comparable spots in each run but it's not precise. We were encouraged though that the data showed lower temperatures. We'll take those anytime.