I just bought a 2007 road glide. This is my first HD; I had a Honda shadow spirit 1100 before. Because I had a metric bike before, I know a lot of metric bike owners. I have heard that water cooled engines are superior to air cooled engines. To me, it seems like that would be true.

Can anyone give me the advantages of an air cooled engine please. The V Rods are supposed to be a hell of an engine and they are water cooled. If water cooled is better, how come the new 96 is air cooled?

 

The 96 is air cooled because that is what most HD Die Hards want. No radiator in front to hide the cylinder, the single pin crank for the lope/sound. One benifit from the engine design is lot's of torque. You may see more of the water-cooled V-Rod engine in other models soon, how many is yet to be seen.

 

Air-cooling reduces weight and complexity and water coolingallows greater control over the combustion temperature, which results generally in more potential power per cubic inch.

FBL

 

First, HD's are based on tradition and a nostalgic styling, and the air-cooled design is a part of that legacy. When people say the HD engine is a hundred-year-old design, they're partially correct, as the air-cooled the 45° V-Twin's basic configuration is that old, but you could hardly compare the design of the first V-twin with an '07 engine.

Water-cooling is better in most ways. They can be manufactured with closer tolerances to reduce mechanical noises. Cooling can be regulated better, as air-cooling has a constant cooling source, which can vary greatly depending on air temperatures, cooling when it doesn't need cooling, like during warm-up. Water-cooling uses fluid that is thermostatically controlled, so warm-ups are much faster. This reduces pollution and increases gas mileage. Making an air-cooled engine today to comply with modern emissions standards is a daunting task, and you can see this in the '07 engine. It runs hot and is choked down to meet emissions and noise regulations. To fix this, the owner must modify the bike which usually makes it EPA illegal. Owning a Harley almost requires the owner to make changes, from EFI or carb mods to mufflers and the intake system.

All this said, these engines have a helluva dose of charisma, and that's why we buy them. They sound right, feel right, and perform the way many of us prefer. So to answer your question, you must first define the word "superior." In theory, and air-cooled engine should be less durable, but that might be if all other factors are equal. They're not, and these can run >100k miles with little or no major repair, assuming proper maintenance. I ran my last bike ('96 RK) 106k miles without any engine work, except for an early cam change and a precautionary lifter change at 65k. It never even required a rocker-cover or base gasket replacement. Can a Honda Shadow last longer? Perhaps, but who will ride their bikes this long anyway? Plus, they just doesn't sound or feel the same, do they?

The water-cooled Harleys are coming, so be prepared. It might not be next year, but it's inevitable. HD can't continue to meet emissions and noise standards with an air-cooled platform, at least not one that can run well. Scuttlebutt is that they are trying to make one that doesn't look water cooled, by hiding the radiator and retaining the cooling fins.

 

I used to be a farmer in Eastern NC. Having experience with all sorts of mechanical things, i can tell you from experience....an air cooled engine is generally much more reliable than a water cooled.
No radiator
No thermostat
No Water pump
No water hoses to bust
No anit-freeze to buy and keep up in the winter months
We started out w/ a Allis-Chalmers K2 Gleaner grain combine (water cooled) and eventually bought a R50 Gleaner with the Deutch air cooled engine. Never had a minutes trouble with the engine. The K2 we replaced the water pump every year, always during the peak harvesting time and could never get the heater to work properly in the winter.
Now i know compairing a combine to a HD is like apples and oranges, but you get my point. There is definatley less to break down. How many cars have you seen stranded by the roadside with a overheating problem????? I have never seen a HD with a busted radiator.

 

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But what happens in heavy traffic or in a parade? I saw plenty of bikes pushed to the side of the parade route at the 100th because of heat and there are just a few threads here about the extremes we go to to coolthese air cooled engines with oil coolers, different pipes, oils etc.

 

Ive got a problem with my bike I bought new this winter,The dang air conditioner was stuck on hi all winter,then the other day we hit 90 down here....wouldnt you know it ..freaking heater stuck on high...If you never owned a harley before good luck,one of two things will happen,you will love it so much youll never buy anything else....or you will hate it and never buy another....good luck..

 

No disrespect intended, but why would you go out and buy a HD and then tell us how much better a water cooled engine is?

Harley buyers want an air cooled V-Twin that sounds & looks cool, it's a lifestyle to most.

After 100 years + I think they work fine. An air cooled engine could get too hot, and a water cooled engine can blow a hose and then get way too hot.

 

I got the same problems, think HD will issue a recall?[sm=teetertooter.gif]

 

I know the newer harleys have a 'fail-safe' thermostat tied to the engine. If it gets 'too hot' where damage may occur they are supossed to shut themselves down so no catastrophic failure occurs.

People will make mods to their bikes for hotter temps or parades. As a for instance there is a 'parade' mode mapping which can be put on your bike for parades to aid in the heat issue. You can put deflecters to keep some of the heat off of your legs and not cook. People who have to deal with stop-n-go traffic or high temps typically will install an oil-cooler which triggers somewhere around 180-185 degrees. They have turbulaters in them to mix the oil and do help in keeping the oil a little cooler. There are relocaters for the HORN on the left side so you can move your horn and install a FAN in it's place to help cool the fins down. With the '07 lines they are already so lean out of the box you do almost have to make a few mods to them to take out so much of the lean they come with. That will lead to overheating quicker.

Those are some of the options you have to help compensate hot air-cooled engines.

Hogs aren't designed to go parade-speed too much. Same could be said for the rice-burners out there. The gearing in them is totally not for parade modes as those are just wanting to 'fly'.

Air Cooled is nice when you are cruising and have enough air-flow to your engine. They aren't the best for long 5mph rides though. But as has been mentioned.... people don't necessarily buy the bikes for parades. Just like I wouldn't want to go and buy a Ferrari to ride in parades or to be stuck in traffic with. The main purpose is to actually DRIVE them. That is kinda how I look at it. You will find the heat isn't too bad. If I get stuck in bad traffic (usually due to an accident) I just shut it down.