Why does your Harley Davidson overheat?

Answer 1

Considering you haven't really given any specifics concerning the bike itself, I will assume you are talking about the newer Twin Cam bikes to start out with.

It's really pretty simple: with new government EPA mandated emissions guidelines, Harley Davidson was forced to impliment a new mapping in the bike's computer to lean out the fuel to meat these new regulations. By doing so, the engine doesn't have the ammount of fuel to help cool the motor. That's right, the cooler fuel that is fed into an engine helps to cool it. A lean engine is a hooter running engine.

You have several options to help remedy the problem. First, you can have your computer remapped to allow more fuel to help cool the engine. This usually makes a big difference. Second, you should switch to synthetic oil such as Mobile 1 V-Twin or the Amsoils are very good. Even the Harley Davidson synthetic oil is far better than conventional. There are a few older mechanics out there that do not fully understand what makes the full synthetics better and will actually tell you that conventional oils are better in the V-twin, FALSE. They think the only difference is that synthetics last longer so if you change you oil frequently it just isn't worth the expense. I actually heard a couple individuals state that they have more luck with conventional and even give some kind of reason for their answer which will be something like, "I found that there is less internal scarring on bearings and cylinder wall with conventional". Go ahead and ask them to give you their scientific research that they ran in accordance to scientific specificatios....They won't be able to suply you with any because they haven't done any, it's just their unfounded oppinion. But this is a whole other story. The fact is, synthetics are created to have a superior heat tollerance with far better viscosity breakdown protection. most have nano-technology used to create micro lubrication. In other words- It is slicker and lubricates far better and yes, it even dissipates better which decreases engine temperatures around 12deg.f when tested. Third, you can install an oil cooler. These units work well when the bike is in motion but are minimal when sitting still idling. You will probably want to install a aftermarket fan that is designed to fit on the oil cooler so as to keep air flowing over the cooling fins when the bike is in traffic sittinf still. There are several companies that produce these fans for the coolers and they do work. They are not as efficient as when the bike is in motion but any time you move fluid threw a cooler that provides a surface that is in contact with air, it will cool. There are claims of 18-20deg.f drop in oil temps when in forward motion and 12-14deg.s f drop in oil temp when sitting still if there is a fan included- They only cool about 3-4deg. f if there is no moving air or a fan.

To go for the maximum cooling effect, use all three. Have your computer re-mapped, put in a good synthetic and add a cooler with a fan and you should be fine from there on out. Erik @ the Enigma Co.s

Hopefully this is what you are asking for, sorry if it is not.