I just got a call from mechanic thats doing my 103ci build and he reccomended an oil cooler as the inside of the case and jugs appeared to be bronzed slightly. Appearently the motor had gotten very hot at one point in time and caused this. Ok now it did happen in Laughlin last year at the rally, waiting to get across the bridge from Bullhead...was in line for about 1.5hrs. and it chugged abit prior to shutting her down. Does anyone have experiance with the cooling fans? Where does the horn get remounted? Does the fan cool better than the oil cooler or is it just that it functions while not moving? I sure would appreciate any comments. Oh and i am in Tucson where riding in 100 degree plus weather is the norm.

MIke
03 RK White Pearl
Soon to be 103ci

 

You will have several different opinions on this topic. First the oil cooler, an oil cooler works the same way as a radiator, the fluid moving throught the coil is cooled as air travels throught the fins of the radiator. Think about when your stuck in traffic in your car. The water temp rises until the cooling fan kicks on and starts to cool the radiator fins. If that fan was not there the car would overheat even with the radiator. While the car is in motion your fan will not ever turn on because of the air that is already moving through the cooling fins, which is cooling the fluid inside. So, it is my opinion that an oil cooler is almost worthless on a Harley or any type of motorcycle. I think the fan would be much better. You can't move the heat without moving the air around the cooling fins. Just my opinion.

 

I heard on http://autos.groups.yahoo.com/group/ultraclassic/ just yesterday that the fan is the better cooling unit. Someone said if the bikes not moving the oil cooler does you no good. I would imagine to some extent this is correct but it would take longer to heat up the extra oil so if would buy some time.

You’ll also notice the Ultra pictured on that message board home page is equipped with a fan.

Personally I think these engines are built pretty tough. I would get your 103 put on the dyno and have them set it up on the rich side and call it good. But I’m not engine guru so maybe that’s bad advice.

 

strtgld Has the best example of why I think the cooler is a waste of money unless you put it on AFTER the fan.

 

I just purchased fan set-up and am planning on cooler later. I have a FLHTCI and horn is relocated under the fairing. Thought fan would be worth it while idling in traffic or whatever, while moving oil cooler would probably work O.K. Just my two cents worth.

 

THE FAN IS DEFINITELY BETTER FOR SLOW MOVING TRAFFIC. .THE COOLER HELPS FOR HIGH SPEED PROLONGED RIDING BUT WONT HELP IN STOP/GO TRAFFIC. SETTING UP ON THE RICH SIDE WILL HELP. JUST NOT TOO RICH.

 

I have purchased both the fan and the preimum oil cooler for my RK. I plan on making a slight modification to the base plate of the oil cooler that pushs it out a bit more and allows me to install another fan in behind the oil radiator. This will be powered off the fan power circuit and an additional relay and fuse as well. The modification will allow both fans to operate from the same thermostat and allow the oil to be cooled by forced air when the bike is at a stop for prolonged periods.

This will allow both to function at thier best. Plan on having both installed before summer heat starts kicking.

 

Ram,

How did the installation of the fan behind the oil radiator work out? This seems to be the best use of the Oil cooler in stop/ go traffic.

 

I agree with what was already stated, if your over heating problem is when your stopped, the fan is a better solution. On my Ultra, with my S&S VFI engine management system, I can monitor the engine temp with my laptop. When I am running it and the temp gets over 250 deg while idling, which don't take long, I turn on the fan and it pulls it down approx 20 deg. Then it slowly starts to heat up again to that 250+ range, so it's not the total solution, but it helps. I did not like the thermostatic switch, so I wired it to my acc switch to just use when needed. I see a lot of people that sit at a train crossing for example with there engine running way to long in my opinion. I have both, an oil cooler and fan on my 107" turbo engine, no heating problems.

 

I would go with both fans for added protection.
The oil cooler for for riding(in motion) in high temp areas and the engine fan for sitting in traffic.
It would be best to avoid sitting in traffic.1.5 hrs in line?Now thats extreme.