Author Topic: Ram Air (Read 8758 times)

aspire61 · « **on:** March 03, 2013, 03:13:24 PM »

Hello fellow riders:

I went out for a 250 km ride yesterday. The weather was a bit chilly but had an absolute blast. My question is about the ram air. It is spec'd as adding 5 horsepower, but i was amazed at how quickly i accelerated from 120 to 180 kph in overdrive. Does anyone know where that 5 hp number came from? I would suspect that number could change based on speed, headwind and temperature. Five hp doesn't sound like a lot, but i seemed to have a lot of available power. Temp was 7 C, which i think (??) would add hp. Any advice would be welcome.

chrs- mat

maxtog · « **Reply #1 on:** March 03, 2013, 03:40:19 PM »

Quote from: aspire61 on March 03, 2013, 03:13:24 PM

I went out for a 250 km ride yesterday. The weather was a bit chilly but had an absolute blast. My question is about the ram air. It is spec'd as adding 5 horsepower, but i was amazed at how quickly i accelerated from 120 to 180 kph in overdrive. Does anyone know where that 5 hp number came from? I would suspect that number could change based on speed, headwind and temperature. Five hp doesn't sound like a lot, but i seemed to have a lot of available power. Temp was 7 C, which i think (??) would add hp. Any advice would be welcome.

That is a good question. I have seen the 5hp number several times, yet I do not really know the source. I think I saw it on something official from Kawasaki at some point, so I do tend to think it is real. Physics-wise, I don't think the compression from the ram air effect on such a small intake is all that much, which is why the performance difference is not that much. The potential pressure will rise with the speed, of course, but the engine will also be using more air in that same gear when going faster.

Generally, nothing amazes me while in overdrive in the Concours

6th gear is really a "wet noodle", and the RPM range while using it is typically WAY below the Concours' performance band.... (well, pretty much always at legal speeds). It is a true overdrive and designed to raise fuel economy and lower engine speed as much as possible to make for the most comfortable cruising option (vibration, noise, friction).

gPink · « **Reply #2 on:** March 03, 2013, 04:18:19 PM »

Not being a physicist, I doubt air intake caused by forward momentum of the motorcycle has a higher velocity than the air being sucked in by the intake strokes of the pistons. At best the 'ram air' effect may relieve some negitave pressure in the air box. I'm somewhat sceptical of excessive hp claims.

VirginiaJim · « **Reply #3 on:** March 03, 2013, 04:40:45 PM »

Dodge?

gPink · « **Reply #4 on:** March 03, 2013, 04:45:01 PM »

Quote from: VirginiaJim on March 03, 2013, 04:40:45 PM

Dodge?

My Dodge get 12 ~~mph~~mpg no matter how fast the air's getting rammed.

red

VirginiaJim · « **Reply #5 on:** March 03, 2013, 04:46:16 PM »

You must have a black Dodge. Mine goes faster than 12mph (silver).

aspire61 · « **Reply #6 on:** March 03, 2013, 05:47:39 PM »

Not being a physicist, I doubt air intake caused by forward momentum of the motorcycle has a higher velocity than the air being sucked in by the intake strokes of the pistons. At best the 'ram air' effect may relieve some negitave pressure in the air box. I'm somewhat sceptical of excessive hp claims.

Interesting - I thought the ram air was the "secret spice" of the 1400. Since I'm not a physicist either, you could be right. Have you noticed your bike has more power in cooler temperatures or lower elevations?

stevewfl · « **Reply #7 on:** March 03, 2013, 06:01:37 PM »

Bet my C14 would have 5 more HP if I changed the air filter.

gPink · « **Reply #8 on:** March 03, 2013, 06:40:53 PM »

Quote from: aspire61 on March 03, 2013, 05:47:39 PM

Interesting - I thought the ram air was the "secret spice" of the 1400. Since I'm not a physicist either, you could be right. Have you noticed your bike has more power in cooler temperatures or lower elevations?

I've not had this bike at elevation yet but no difference at temp. All the twins I've had always ran better in cool low humidity weather

maxtog · « **Reply #9 on:** March 03, 2013, 07:30:16 PM »

Quote from: aspire61 on March 03, 2013, 05:47:39 PM

Interesting - I thought the ram air was the "secret spice" of the 1400.

Oh no. The secret spice is that the Concours is using the same engine as the fastest stock street motorcycle, the ZX14. It is a big, modern engine with 4 cylinders, decent compression, 16 valves, fuel injection, variable valve timing (C-14 only), etc. The ram-air has almost no place in the overall picture.

One of my more favorite sayings- "there is no replacement for displacement."

Cuda · « **Reply #10 on:** March 03, 2013, 07:44:51 PM »

It's not the ram air forcing more air in to make more HP it is cool dense air that makes a big HP difference , we have to change our ECU settings on our outboard drag boats depending on many factors , many guys have air stations to help us set the ECUs , then we make test passes , pull out a spark plug to zero in on the tune for the race.

stevewfl · « **Reply #11 on:** March 03, 2013, 07:46:27 PM »

Quote from: Cuda on March 03, 2013, 07:44:51 PM

It's not the ram air forcing more air in to make more HP it is cool dense air that makes a big HP difference , we have to change our ECU settings on our outboard drag boats depending on many factors , many guys have air stations to help us set the ECUs , then we make test passes , pull out a spark plug to zero in on the tune for the race.

PICS PLEASE!

Cuda · « **Reply #12 on:** March 03, 2013, 07:50:56 PM »

I'm not a picture kind of

VirginiaJim · « **Reply #13 on:** March 03, 2013, 07:57:48 PM »

Quote from: gPink on March 03, 2013, 04:45:01 PM

My Dodge get 12 ~~mph~~mpg no matter how fast the air's getting rammed.
red

Sorry about that. Red is still a slower color (not as bad a black) and evidently likes to drink the suds a bit more than mine.

Cuda · « **Reply #14 on:** March 03, 2013, 07:58:37 PM »

I design and build these as a hobby.... a very $$$ hobby

Cuda · « **Reply #15 on:** March 03, 2013, 08:07:45 PM »

I just drove home a new to me 2009 Ram diesel 4x4 6 sd. auto, got 18 to 19 mpg at 76 to 80 mph, from Tupelo MS. to naples fl . must have been the air

H&S 5" SS exhaust DPF deletes egr removed . about 400HP 700 ft lb tq. YEEEEEHAAAA

ZG · « **Reply #16 on:** March 03, 2013, 08:24:46 PM »

Quote from: VirginiaJim on March 03, 2013, 07:57:48 PM

not as bad a black

Madcow · « **Reply #17 on:** March 03, 2013, 09:05:44 PM »

Quote from: gPink on March 03, 2013, 04:18:19 PM

Not being a physicist, I doubt air intake caused by forward momentum of the motorcycle has a higher velocity than the air being sucked in by the intake strokes of the pistons. At best the 'ram air' effect may relieve some negitave pressure in the air box. I'm somewhat sceptical of excessive hp claims.

Here's an artical about the effects of ram air.
http://www.sportrider.com/tech/146_9508_ram/viewall.html
Ram Air Test: Part Deux
http://www.sportrider.com/tech/146_9912_ram/viewall.html

martin_14 · « **Reply #18 on:** March 04, 2013, 06:52:06 AM »

the RAM thingy that this bikes come with, and any well thought out air intake, for that matter, is not designed to increase the speed of the air coming in the cylinders, but the pressure. The intake itself is smaller than the ducts, so the air expands, decreasing its speed and increasing its pressure (Bernoulli effect). It's like a turbo, just milder, and it only works at high speed, since you're converting air speed into air pressure.
Now where's Brian?

connie1 · « **Reply #19 on:** March 04, 2013, 08:22:32 AM »

My Ford diesel gets pretty good mileage but in some conditions it gets great mileage. I think temps a few degrees above or below freezing and high humidity get more air into the cylinder and/or increases the volume of the air as it is burned. That's my theory. Does that same concept transfer over to a gas job? ?
I remember seeing water injection on some big jets and I guess the concept would be the same. Someone on here probably has first hand knowledge.

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Author Topic: Ram Air (Read 8758 times)

Madcow