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Discussion Starter #1
This is an idea I have been pondering for a while and I finally think I have a worthwhile concept started here. A ram air intake consisting of a oil funnel, some corrugated tubing, and some way to affix it to the intake tube with a hose clamp b4 the air cleaner element. Any thoughts?
 

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Top speed

It might improve top speed a little if you can really scoop up any preasure and don't restrict the air intake at non pressurized speeds. The bodywork of the VFR1200 uses the gaps on either side of the headlight that we also have, for air rams. Ours just kind of flow in and back out.
 

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All the oil funnels I own have a relatively small opening (designed for holding quart bottles upside-down)... isn't that more restrictive than stock? Perhaps a PVC pipe-end would be better, mimicking a velocity stack. The pictured oil funnel has an offset hole which would mean uneven velocity entering the intake.

I imagine finding space for it would be difficult, and blocking airflow to the radiator isn't a great idea. In terms of the picture you're using, the placement is backwards since the exhaust manifold faces the front of the bike.

Also not so sure about the corrugated piping. I realize it's necessary for flexibility, but I would venture a guess and say the segmented "accordion" surface would add some turbulence.

The ram air affect might be negated by the added length of piping, especially if it has to be bent 180°. I'm no expert, just thinking out loud. The only true test to your theory would be a comparison of before/after dynos.

A small correction: forced induction generally refers to active systems, like turbo- or superchargers. I don't think a ram air intake qualifies.
 

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Any benefit would be only from the cooling the air... even then negligible.

like the way your bike always runs better at night.
 

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This would be interesting to see done. Maybe a bit higher quality materials on the finished product.

Why doesnt this forum have a whole DIY section??? I used to frequent the DIY section in all the car forums. It's awesome to see what people come up with.
 

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Because Mr Honda has done all the homework for us.
 

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This is an idea I have been pondering for a while and I finally think I have a worthwhile concept started here. A ram air intake consisting of a oil funnel, some corrugated tubing, and some way to affix it to the intake tube with a hose clamp b4 the air cleaner element. Any thoughts?

Not to piss in your cheerios, but you have the tube pointed backwards. Also, the engine is tuned for 1ATM of static atmospheric pressure. If you ram air, you will use more air, and more fuel. Honda engineers decided against that performance/economy tradeoff.
 

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Discussion Starter #9
Ok... gonna try to answer multiple questions here...lol. Obviously when I build it i am going to use a tube only about 1 ft in length, the tube would be about 2" in diameter (so as to not restrict low speed performance) and i would use a regular funnel (not offset), cut it off on the bottom to give it a 2" opening and epoxy it to the hose, the diagram is just a very basic concept.... hence the funnel will be facing forward in the fairing.

Ill have to work on an x-ray view but that gonna take a lot -o- photoshoppin'.
 

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Drugs are baad Mkay!?
 

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You have the funnel completely the wrong way round~

 

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I remember reading that the air funnels on many bikes only start to become effective at extremely high speeds, speeds much higher than the cbr250r is capable of.
 

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This is a complete waste of time.
Oh man... your totally right. "thinking" is a waste of time. we should all just sit around and never think again. now if only Einstein or Tesla had gone with that attitude. thanks for your intelligent input.
BTW... laying the sarcasm on pretty thick in case your slower than normal thought process didn't pick up on that:D Turn the gas down flamer....
 

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Mongoose, it is not that Tesla or Einstein would have thought that way, it would be their friends and associates. Those guys were too busy experimenting to get everyones thoughts first. Which is good, beause most people will shoot down an idea they dont understand or didnt think of. They failed a lot, which refined their discoveries. try the funnel, good luck. I think the moto3 bike has the cylinder backwards, with the intake in the wind, not the first engine to do this, but probably the best way to do it. A lot of hood scoops were added to the muscle cars in the 60s and 70s
 

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And we all remember when the ZZR1100 came out in 1990 marketed with Ram air.

Get your cbr up to 300 and lemme know what you felt.
 

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I have done some simple calculations with some assumption and if:
- ECU self adjust to the new airflow instantly
- 4 inches diameter funnel to 2 inches diameter tube with smooth transition (smooth finish, short tube)

You might get at best (if my calulations are correct),
0.9% increase in engine performance at 100 km/h (65 mph)
1.5% increase in engine performance at 150 km/h (90 mph)

I also found that variation in performance should not be impacted much by tube size for tube bigger than 1 inch in diameter.

I personnaly would use a bellmouth to reduce pressure loss instead of a funnel. (search google image for bellmouth)

(calculations done only considering dynamic pressure)
 

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Here have a read-

Tuning the LET - RAM air history and facts

Then forget any romantic notion of Ram air on this bike.. If it did work it would have it and so would every other bike out there produced in the past 20 yrs.

Insulate your airbox from heat yes.. (see my first post here re cool air)
but you'll never get any benefits of ramming air into it.. (not unless you are doing 300kph)
think of your engine as a pump.. it only pumps a certain amount of air.

Been around bikes long Mongoose?
 

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Oh man... your totally right. "thinking" is a waste of time. we should all just sit around and never think again. now if only Einstein or Tesla had gone with that attitude. thanks for your intelligent input.
BTW... laying the sarcasm on pretty thick in case your slower than normal thought process didn't pick up on that:D Turn the gas down flamer....
No need to be a smart ass dude! The fact is that it will do absolutly nothing for this bike. Unless you somehow get your 250 to go 160MPH it is a waste of time. Use your einstein brain power for gearing and engine mods. It's just my opinion. I would rather build a motor that puts out power with internals than mess with little trinket stuff like that.
 
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