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German Rider
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If on a straight level road, you need HP to go fast instead of torque, but if you want to go uphill, you'll need torque instead of HP to make it.
Same on cars.....
Gas = HP = fast
Diesel = Torque = pulling power

Cu,
Sven
 

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Rider
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Anyone know what type of cooling a 10,000 hp top fuel dragster has?
I used to be in the Merchant Navy and talking of 10,000 BHP engines the vessel below had four Ruston V20 Heavy Oil engines that would produce 10,000 BHP each at a little over 1100 RPM. They were cooled by water. The sump that had a ton of oil by weight in it had to be constantly heated or the engine wouldn't turn over on start. Not efficient or cost effective by far nevertheless they got the job done! 180 cars and 740 passengers and could still do over 40 knots on a good day!

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Ok I understand this. But water cooled is controlled by fan and more surface area air is realigning on air flow which is not constant. Still struggle to see how air is equal to air in heat removal
Your original message was that people who ride water cooled bikes don’t complain about the heat and that’s not true. Water cooled bikes make heat too and it’s just as uncomfortable. And to your point of water being more efficient than air. If the water removes more heat from the engine because it’s more efficient where does that heat end up? Right between your legs with a fan blowing back at you. Air cooled engines are not bad just different. I have had some very fast air cooled bikes. The old Japan in-line 4 cylinder bikes made Hp at higher rpm (11000rpm+), had overhead cams and were air cooled.
 

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To add o Rides' post, coolant pumps and fans add to the engine's load, which take away from torque and hp. Throw alternators into this pile as well.
 

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Discussion Starter #45
Your original message was that people who ride water cooled bikes don’t complain about the heat and that’s not true. Water cooled bikes make heat too and it’s just as uncomfortable. And to your point of water being more efficient than air. If the water removes more heat from the engine because it’s more efficient where does that heat end up? Right between your legs with a fan blowing back at you. Air cooled engines are not bad just different. I have had some very fast air cooled bikes. The old Japan in-line 4 cylinder bikes made Hp at higher rpm (11000rpm+), had overhead cams and w
water is over 3000% more efficient at heat transfer that is law of pyhics. Any large area is heated and cooled with water. Water cooled bike has more surface area to cool so lower temps are achieved and controlled. Air is controlled by moving which is not controlled. This is laws of pyhics
 

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Discussion Starter #46
Look at design a on TS engine there are two spray nozzles at base of piston spraying oil at hottest part of cylinder in effort to reduce temperature. It is my understanding this is to provide much needed cooling at the source. Which proves to me that by design heat removal is a issue
 

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Look at design a on TS engine there are two spray nozzles at base of piston spraying oil at hottest part of cylinder in effort to reduce temperature. It is my understanding this is to provide much needed cooling at the source. Which proves to me that by design heat removal is a issue
Most newer engine designs use an oil spray to cool the base of the piston. This is not dependent upon the cooling source. The 6.2L engine in my pickup uses the same type of oil spray system.
 

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water is over 3000% more efficient at heat transfer that is law of pyhics. Any large area is heated and cooled with water. Water cooled bike has more surface area to cool so lower temps are achieved and controlled. Air is controlled by moving which is not controlled. This is laws of pyhics
I don’t think anyone here is denying that water conducts heat better than air. Not sure where you are going with this. There are multiple ways to cool an engine and if the cooling system is designed properly it doesn’t matter what it uses as long as it works. This is like arguing over what cylinder arrangement is best v twin, v4, in-line, boxer who cares they all have their place and pros and cons. if you are saying the rider gets less heat from a water cooled bike than an air cooled bike my experience does not support that.
 

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There are multiple ways to cool an engine and if the cooling system is designed properly it doesn’t matter what it uses as long as it works.
One of the big advantages of water cooling is that it is capable of keeping the engine temperature within a narrow operating range by using a thermostat and fan(s) behind the radiator, regardless of the circumstances. An air cooled engine typically runs very cool on long freeway stretches, especially in the rain, autumn/winter, but tends to run very hot at slower speeds on the summer. It needs to be designed to run within a far wider temperature range than a water cooled engine, often using wider tolerances.
 

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Rider
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Back when I had my scout one the things that was annoying was at a light the fans would kick on and blow very hot air up my pant leg.

As someone else mentioned, since water is better at removing heat that heat has to go somewhere. When it comes off a radiator in front of your legs it's often hotter than what is coming off an air cooled engine. So your engine is less likely to overheat at a light on a hot day, but if the radiator fans are blowing up your pant legs YOU might overheat faster :p
 

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Discussion Starter #54
One of the big advantages of water cooling is that it is capable of keeping the engine temperature within a narrow operating range by using a thermostat and fan(s) behind the radiator, regardless of the circumstances. An air cooled engine typically runs very cool on long freeway stretches, especially in the rain, autumn/winter, but tends to run very hot at slower speeds on the summer. It needs to be designed to run within a far wider temperature range than a water cooled engine, often using wider tolerances.
Yes. Thank you
 

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I'm suddendy thinking of the Benelli Tornado Tre 900, that had the radiator under the seat (to keep the bike's silhouette narrow), and a few fans to get rid of the heat....

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water is over 3000% more efficient at heat transfer that is law of pyhics. Any large area is heated and cooled with water. Water cooled bike has more surface area to cool so lower temps are achieved and controlled. Air is controlled by moving which is not controlled. This is laws of pyhics
I think your point is that liquid-cooled engines are better. That's a flawed argument.

Better than what?

"Better at managing heat". Okay, but where?
"Better at managing heat in the engine". That's true, but so what!

They are "not" necessarily better (or worse) than managing the heat that the rider feels, although they might be different.

Liquid cooled engines do allow designers more freedom to design the engine, so it's easier to increase rpm, horsepower, etc. etc.

But not everyone (and I suppose almost none of us considering we're in the Indian forum) wants a 200mph plastic machine that sounds like a sewing machine.

There's no "better". A boxer (aircooled) engine is different from the vtwin (aircooled) engine which is different from a liquid-cooled v-twin which is different from all other engine configurations.

The fact that BMW for its entry into cruisers chose an air-cooled power plant shows that the rumours of air-cooled's demise is greatly exaggerated.
 
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