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Gimmick said:
Funny to see he has the exact same dip, even though it's 250 rpm higher up. Maybe has something to do with the geometry of the XX engine/head/cams/carbs/airbox? (but FI Birds have the same dip, so maybe not carbs and airbox)
I would suggest the dip has been built in for noise testing purposes. Whilst emissions control varies by country and year, engine noise (not just exhaust noise) has been present for many years .... Euro 4 (that comes into play for all new bikes this year) tightens the requirement even further.
 

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I would suggest the dip has been built in for noise testing purposes. Whilst emissions control varies by country and year, engine noise (not just exhaust noise) has been present for many years .... Euro 4 (that comes into play for all new bikes this year) tightens the requirement even further.
for the love of God Duck, please don't get sound tuning into this. I can't explain how freq resonance effects power, or more I won't (10 years with an international company that did exhaust for everything from ATVs to super cars and yes I have hand built proto types for some of them).

or is it a by product of the cams :evilaugh: (different rpm range due to the carbie and FI having diff exhaust cam profiles)
 

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RC46, apparently I didn't give the "wanted" answer so I am wrong lol everyone wants to compare dyno crap data without the airspeed to make the ram air FUNCTION. It will not work with the bike stationary on a dyno. If anything I can see it hurting hp with the added twists and turns of the duct work.

Partsguy, you say your carbie was always about 3mph slower through the trap. You can bang on the stationary dyno drum all day long, doesn't make it fact. You say the HEAVIER FI Bird (we can all agree the FI was heavier right?) was always 3mph faster through the traps.... what does it take to get a heavier vehicle to go faster in a given distance?....... MORE POWER. If you raced I assume you understand that it would take a notable increase in power for a heavier machine to not only catch up to but surpass a lighter, identical machine. I also assume you understand that the carbie has slightly more rotating mass (clutch plates) which would store more energy for launch. true it's only a few ounces but at 5,6 or 7000 rpm launch it's an advantage none the less, especially on a lighter bike. You can't argue with physics. While on physics let me bring up another advantage the carbie has off the line, the CV carbs. They will only open as much as the engine has demand for thus keeping intake velocity higher than a FI Bird (does not apply to WOT of course and by that I mean the slides not your wrist). Air has mass and we all know that objects in motion tend to stay in motion unless acted on by an outside force. This is a little tricky for me to explain but I'm going to try. With a CV carb the intake velocity stays high because the path is restricted. What this does is that when the intake valve opens air/ fuel is sucked into the engine and the entire mass of air in the air box begins to move. when the intake valve closes that mass continues to move and piles up against the valve creating pressure. Over a certain rpm this pressure does not have time to completely dissipate as a revision pulse and is now a pressurized "puff" that gives the intake charge a head start if you will on it's way into the cylinder. On the FI bikes you are in direct control of the throttle, you open it up at launch and the throttle bodies are capable of providing much more flow than required and the intake velocity drops. Now you don't have that little "puff" of stored energy in the moving mass of the incoming air/fuel mixture. At 5000rpm the intake valve opens just over 41 times per second. That is 164 times per second for all 4 cylinders now assume you pack in an extra 2cc of fuel air mixture per opening because you have a higher intake velocity. That is 328cc per second more fuel and air you are getting into the cylinders. Each cylinder is only 284.25cc. The engine is 1137cc x 41 (intake strokes per second @ 5000rpm)=46,617cc (@100% efficiency, never gonna happen). Having CV cabs should mathematically give just under 1% better volumetric efficiency, another slight advantage over FI off the line.

So now you have more rotating mass, less total weight and better volumetric efficiency at launch. How is it that the FI Bird is able to be faster through the traps? MORE POWER that you don't see on a dyno but you do have in the real world. You are highly discounting the pressure wave that is in front of the Bird at 185mph (where the 164 gross hp comes from), this is pressure that is fed into the engine at speed, it's a free, low boost turbo that you can't measure on a dyno without a wind tunnel and I would not put it past honda to have used a dyno during wind tunnel testing of the Bird.

I have been on my both of my bikes, carbie and FI with a damn good friend on the other. 0-100, carbie wins hands down regardless of rider. after 100 the FI walks away from the carbie (even with 90k more miles on the clock and without the PC) doesn't matter who rides it. btw, no one claimed 164hp at the wheel on any stock Bird, Honda numbers are gross not net.
 

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I would suggest the dip has been built in for noise testing purposes. Whilst emissions control varies by country and year, engine noise (not just exhaust noise) has been present for many years .... Euro 4 (that comes into play for all new bikes this year) tightens the requirement even further.

VIN plate states 90dba at 4750rpm
vin.jpg
 

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Cheers mikey
VIN plate states 90dba at 4750rpm
which generally corresponds with the start of the dip in dyno charts but after commrads heartfelt plea I had better keep quiet on this one!

When at work I was likened to one of these 2

StatlerandWaldorf(2).jpg

I have a habit of lobbing in the occasional metaphorical grenade and then sitting back :smilebig:
 

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He better be a GOOD friend if on my bike at 100 plus!
 
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Discussion Starter #28 (Edited)
RC46, apparently I didn't give the "wanted" answer so I am wrong lol.
No one has contested your answer, or did I miss something? Everyone was free to chime in, no wanted or unwanted answers in an open debate.

So carbies are quicker and FI's are faster, I think I've heard that one before.

Let me recap the figures from Performance Bikes Magazine
'97 - 132.9 RWHP - 76.4 lb-ft RWTRQ - 555 wet weight - 41.7 MPG - 170 MPH top speed - 2.91 0-60 - 6.06 0-100 - 10.24 1/4 @ 134.52 - braking 60-0 (ft) 112.4 - P2W 1:4.18
'99 - 134.4 RWHP - 80.0 lb-ft RWTRQ - 563 wet weight - 40.5 MPG - 174 MPH top speed - 2.91 0-60 - 5.99 0-100 - 10.24 1/4 @ 136.98 - braking 60-0 (ft) 115.3 - P2W 1:4.19

trap speed (and weight) are higher for '99, but so is the RWHP and torque. equal 0-60. RAM air is showing at 0-100 and the trap speed, but I still see no reason to assume the rated 164 hp was including RAM air, since the carb Birds did not have RAM air.

From the 1999 press kit:
While the CBR1100XX’s cavernous 9.5-litre aircleaner still receives a steady stream of cool outside air from the two ports located on either side of the fairing’s upper cowl, the two nose ports that used to direct air only to the oil cooler are now connected to a pair of specially designed intake ducts that feed large volumes of high-pressure air directly into the aircleaner for a major boost in top-end power and high-speed performance. The only visible outside difference is in the replacement of the screens positioned immediately behind the port entrances of the current model by a set of vertical louvres positioned deeper in the duct to keep insects and other foreign objects from entering the system while maximizing the system’s free-breathing performance. Specially moulded deep in the one-piece air ducts, the recessed positioning of these louvres ensures a steady buildup of air pressure inside the duct, since the forward-positioned screens of the current model would tend to deflect nearly as much air as they let pass through at high speeds.

Although the ideal shape for these new Direct Air Intake ducts under controlled conditions at full operating capacity might be something closer to a straight tube, in the real world of ever-changing variables the engine’s intake demands when the throttle is snapped opened at lower speeds would suck all the air out of the ducts before a speed could be reached that would create enough air pressure to sufficiently replenish the air in the system. Therefore, the Super Blackbird’s new Direct Air Intake ducts were designed with uniquely shaped largevolume air cavities that Ensure a steady supply of air to the engine for quick acceleration from all speeds.


Notice they say: a major boost in top-end power and high-speed performance, very specific circumstances and not a claim about general engine output. Now the interesting question is, why didn't they put RAM air on the carb models in the first place, since it was designed as a high-speed motorcycle. The answer is probably they couldn't make it work like Kawasaki did in 1992 on the carbed ZX-11/ZZR1100: "While ram-air may increase the volumetric efficiency of an engine, they can be difficult to combine with carburetors, which rely on a venturi-engineered pressure drop to draw fuel through the main jet. As the pressurised ram-air may kill this venturi effect, the carburetor will need to be designed to take this into account; or the engine may need fuel-injection." https://en.wikipedia.org/wiki/Ram-air_intake

More reading: RAM AIR TEST | Sport Rider

And from Ram Air Test: Part Deux | Sport Rider :
**HONDA CBR1100XX: **Well what would you rather have-115 horsepower or 122 horsepower? The CBR-XX obviously reacts well to ram-air induction. The horsepower and torque curves literally mimic the non-ram-air graphs, only with a five to seven horsepower increase and three to five additional foot-pounds of torque. It should be noted the Honda XX's ram-air system is one of the most efficient on the market, showing immediate power gains well before the 7000-rpm starting mark and posting high-pressure readings during our top-speed test. For comparative purposes, the CBR-XX's pressure reading without ram-air assist at full-throttle/top rpm was -8mb.

*It should be noted that Eddy Current dynos typically give horsepower readings 15-20 percent lower than the more common Dynojet dyno readings.
I have a 98 carbie and an 01, 49 state US bike. The carbie is a little quiker from 0-100 (I'd guess because it weighs less and the CV carbs keep the intake velocity higher during acceleration) but after 100mph the 01 seems like it has more than a 12hp advantage. More like 20hp because as the air pressure in the air box increases so does the amount of fuel dumped into the engine.
So even if we multiply 7 (122-115) by 1.2, we are no where near 12, let alone 20 hp :nono::eyebrows::)
 

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No one has contested your answer, or did I miss something?
Bold text, post number 13.

but I still see no reason to assume the rated 164 hp was including RAM air, since the carb Birds did not have RAM air.
Honda wasn't "competing" with the previous year Bird for sales. Including the gross, ram air hp made the "new" FI Bird look better on paper and wasn't a lie. (if it was found to be a lie, under identical testing conditions Honda would have been sued). The 99 busa had a claimed 175hp (gross, I suspect this number was calculated from a static dyno run but have no proof. we know a stock busa put around 160 to the tire, there are tons of dyno tests to show this). Honda had 3 choices for marketing, RWHP (static dyno), gross hp (static) or gross hp with the ram air in full effect. Pure economics and competition on paper to lure sales alone is enough to assume that they published the later of the three. If you were standing in the showroom about to buy a new Bird or Busa in 1999 and saw Honda publish 135hp RWHP v the Busa with a published 175 gross hp and you are the average Joe it's a no brainier which one sounds better and might sway you on your purchase. Now with both publishing "gross hp" only 11hp apart the average person doesn't see 11hp when they are all starry eyed over buying one of these new super machines, they round it down and think to themselves "that's not even my lawn mowers hp diff".


Notice they say: a major boost in top-end power and high-speed performance, very specific circumstances and not a claim about general engine output. Now the interesting question is, why didn't they put RAM air on the carb models in the first place, since it was designed as a high-speed motorcycle. The answer is probably they couldn't make it work like Kawasaki did in 1992 on the carbed ZX-11/ZZR1100:
To answer this you have to understand how carbs work. Fuel is NOT sucked through the jets. It is forced through the jets from the fuel bowl and injected (at a very low pressure) into the air stream because of the air pressure drop through the variable venturi. If you put ram air on it it would be the same as running a turbo on a carbed bike, you would need to either A: build a very finicky carb that could deal with variable vaccum/ pressure in the air box or B: completely enclose the carbs in an air tight box and use a rising rate fuel pressure regulator to compensate for the rising air pressure.

we are no where near 12, let alone 20 hp :nono::eyebrows::)
I never said it had that, I said it felt like it. (disclaimer: my butt is not calibrated lol).
 

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Discussion Starter #31
lol fair enough, if your butt-to-rwhp conversion factor is 2.86 (20/7) then the Bird feels like it has nearly 350 hp (2.86 x 122) when the RAM V-TEC kicks in, and close to 330 hp without (2.86 x 115) :D
 

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lol fair enough, if your butt-to-rwhp conversion factor is 2.86 (20/7) then the Bird feels like it has nearly 350 hp (2.86 x 122) when the RAM V-TEC kicks in, and close to 330 hp without (2.86 x 115) :D
you completely forgot about the flux capacitor spooling up!! :rotfl:
 

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The FI has to have more hp to pull higher trap speeds. Now where do those extra ponies come from? Both carb and FI have 42 mm throats. The Intake cam in the carb has 3 degrees more over lap (IC- O-20* BTDC) than the FI (IC-O-17*BTDC) while both ex closes 10* ATDC. Assuming the flank profiles are the same on the cams. I suspect the FI being more controllable it does not need those 3* to get fuel flow going to fill the cylinder and for scavenging. Or would the carb scavenge a tad more on top end? Equals less fill/power. Don't know at this point.

Velocity is only part of the game in head flow. With both carb and FI being the same throat size and assuming the ports are the same, I can't see a big difference in velocity/flow rate. Though it would be very interesting to test that hypothesis. Anybody got a flow bench handy?

I've always heard the FI is setup rich all the way thru the power band. This may explain that at lower speeds it's making less usable power compared to the carbs which may be leaner and better burn for speed. On the other hand a rich mixture in the upper rpm band should make more power specially when ram air is used.

I wish I had access to a shop again with all the the toys for measuring engines and power. A nice head flow bench, a fuel flow bench, an engine dyno with air intake flow and all the little transducers that measure what ever you want. I'd be in nirvana.

I would participate in a stock BB get together dyno day someplace if it was within 500 mile or less from me. And yes seeing I have a stock FI bike I'll bring a backpack blower to the scene of the crimes. Gotta test the ram air......................

To me it doesn't matter cause the bird has enough power to put that s#&t eating grin on my face all the time.:popcorn:
 
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Discussion Starter #34 (Edited)
AFAIK, the 164 quoted is the theoretical output AT THE CRANK, and this assumes the engine is built to the original design tolerances, which will never happen in a mass production system (u seen the quotes for how quickly they put these engines together).

The bottom line is that you would never see near that figure unless the engine had been blue printed (ie stripped and built to orig design spec)- not cheap and def not at rear wheel after transmission losses
A side note. When V&M did the 50th anniversary 1200cc Blackbird, after rejetting, porting, new pistons and rods for the 2mm widened bore, new cams with wider opening profile, akrapovic 4-in-1 and adding RAM air plus a higher red line (11,300 or 11,750 according to another source), they got 40 bhp extra, 183.1 bhp on the dyno. Another article mentions 174 bhp on the dyno where a ZZR1400 measured 168 bhp.*

*That's more than 485 commrad-butt-horsepower


To create the FireBird, V&M; starts with a stock, first-generation carbureted XX. V&M; says that "not even Honda Britain could get hold of the access codes for the new model's engine-management system...so we concentrated on the original bike, and built our own pressurized airbox." V&M; strips the stock engines and builds them up with Carrillo billet rods mounted on the stock crank, and 2mm-overbore forged pistons, raising displacement to 1198cc and compression ratio to 13:1 (from the stock 11:1.) The cylinder head is comprehensively re-ported and gas-flowed, before fitting V&M; camshafts with 1mm more lift and 20 degrees more duration. Redline increases 500 rpm to 11,750.
According to V&M;, its 1200XX makes 179 rear-wheel hp at 11,500 rpm on the same dyno on which a stock XX made 137 hp at 10,000 rpm. A full Akrapovic 4-into-1 exhaust system with stainless steel header pipes and a single titanium-wrap street-legal silencer replaces the heavy, stock twin-can system. A Penske rear shock is the only nonstandard chassis part.
Twelve top-speed runs all clustered in the 196/197-mph bracket, with two at 198 mph, is a pretty frustrating result when you're aiming for 200, but an impressive improvement on the stock CBR-XX. On the same tall (stock) gearing the V&M; Bird pulled a 10.15-second quarter-mile at 142 mph.
The CBR1200XX is far more tractable and roadworthy than you'd ever suspect from reading its dyno sheet. It's also a pretty certain license-loser in spite of the rock-steady, wide-spread mirrors, if only because the way the V&M; Honda delivers this performance is so deceptive. Part of the reason for this is how fast the bike builds speed, part of the effectiveness of the pointy-nose streamlining, which in the bright red of Honda's 50th birthday paint job doesn't look nearly as bulbous as in the Stealth Bomber livery of the original Blackbird. Honda's honor, thanks to V&M; (fax: 011-44-161-654-0022), is restored. -Alan Cathcart

Source: V&M Racing's 179-HP Honda CBR1200XX | Fire Bird! | Motorcyclist



http://www.cbrxx.com/general-cbr-xx...fied-blackbird-sold-auction-earlier-year.html
http://www.cbrxx.com/general-cbr-xx-discussion/26796-yeah-baby-someone-here-buy.html
http://www.cbrxx.com/general-cbr-xx-discussion/24567-50th-anniversary-1200xx-blackbird-2.html
http://www.cbrxx.com/introductions/14217-cbr-1200-a.html (this forum member claims to have a 1999 FI power commander bike by V&M with 205 hp)

And look, no dip: http://www.cbrxx.com/attachment.php?attachmentid=49517&d=1404948052
 

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RC46, apparently I didn't give the "wanted" answer so I am wrong lol everyone wants to compare dyno crap data without the airspeed to make the ram air FUNCTION. It will not work with the bike stationary on a dyno. If anything I can see it hurting hp with the added twists and turns of the duct work.

Partsguy, you say your carbie was always about 3mph slower through the trap. You can bang on the stationary dyno drum all day long, doesn't make it fact. You say the HEAVIER FI Bird (we can all agree the FI was heavier right?) was always 3mph faster through the traps.... what does it take to get a heavier vehicle to go faster in a given distance?....... MORE POWER. If you raced I assume you understand that it would take a notable increase in power for a heavier machine to not only catch up to but surpass a lighter, identical machine. I also assume you understand that the carbie has slightly more rotating mass (clutch plates) which would store more energy for launch. true it's only a few ounces but at 5,6 or 7000 rpm launch it's an advantage none the less, especially on a lighter bike. You can't argue with physics. While on physics let me bring up another advantage the carbie has off the line, the CV carbs. They will only open as much as the engine has demand for thus keeping intake velocity higher than a FI Bird (does not apply to WOT of course and by that I mean the slides not your wrist). Air has mass and we all know that objects in motion tend to stay in motion unless acted on by an outside force. This is a little tricky for me to explain but I'm going to try. With a CV carb the intake velocity stays high because the path is restricted. What this does is that when the intake valve opens air/ fuel is sucked into the engine and the entire mass of air in the air box begins to move. when the intake valve closes that mass continues to move and piles up against the valve creating pressure. Over a certain rpm this pressure does not have time to completely dissipate as a revision pulse and is now a pressurized "puff" that gives the intake charge a head start if you will on it's way into the cylinder. On the FI bikes you are in direct control of the throttle, you open it up at launch and the throttle bodies are capable of providing much more flow than required and the intake velocity drops. Now you don't have that little "puff" of stored energy in the moving mass of the incoming air/fuel mixture. At 5000rpm the intake valve opens just over 41 times per second. That is 164 times per second for all 4 cylinders now assume you pack in an extra 2cc of fuel air mixture per opening because you have a higher intake velocity. That is 328cc per second more fuel and air you are getting into the cylinders. Each cylinder is only 284.25cc. The engine is 1137cc x 41 (intake strokes per second @ 5000rpm)=46,617cc (@100% efficiency, never gonna happen). Having CV cabs should mathematically give just under 1% better volumetric efficiency, another slight advantage over FI off the line.

So now you have more rotating mass, less total weight and better volumetric efficiency at launch. How is it that the FI Bird is able to be faster through the traps? MORE POWER that you don't see on a dyno but you do have in the real world. You are highly discounting the pressure wave that is in front of the Bird at 185mph (where the 164 gross hp comes from), this is pressure that is fed into the engine at speed, it's a free, low boost turbo that you can't measure on a dyno without a wind tunnel and I would not put it past honda to have used a dyno during wind tunnel testing of the Bird.

I have been on my both of my bikes, carbie and FI with a damn good friend on the other. 0-100, carbie wins hands down regardless of rider. after 100 the FI walks away from the carbie (even with 90k more miles on the clock and without the PC) doesn't matter who rides it. btw, no one claimed 164hp at the wheel on any stock Bird, Honda numbers are gross not net.
Hey Commrad-chill out.Everything I stated about the performance of the carb model was fact,there was nothing about one dyno vs another,the point,which you missed,was to point about they are about the same and that ram air works and what my experience was racing stock versions of each. Didn't need a 300 word essay of the volumetric efficiency of cv carbs to know that speed traps don't lie.There are too many variables to argue about this shit, but I'll race a stock f.i. against a stock carbie 0-100 any day and we'll see if your side holds up.
 

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Hi Rollin, well said, very complete statement, Honda owns the touring market and that's all. For my next bike I'm going to turn a sport bike Into a sport tour bike instead of the other way around (XX) Honda needs to shoot for the zx14 in an effort to take back the sport tour market. I would think that Honda would take the (XX) model and make something good, better, but nooooooo. Its JUST COMMEN SENSE, HONDA! Build another XX and sell out fast.
 

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Discussion Starter #38
Ok I found an interesting statement in Dutch Honda documentation from 1999. It goes like this:

By introducing PGM-FI the torque in the lower rpm range has increased significantly. The horsepower that is effectively transmitted to the rear wheel has increased by 6%, even though the maximum horsepower measured at the crank has remained the same (164 DIN).

I'm not sure how to interpret that statement...
 

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I can believe it. They also changed the header were the 2/3 pipes are a tad longer which may be part of the increase along with the cam change. Plus they most likely changed the fueling also. The richer fueling should pick up power (torque) vs speed from the leaner carbs.? Which may not change the over all max horsepower just moves it around a little bit. Just like tuning on a dyno normally does, changes when, where and how much power is made.

At least that's the way I see it. One other thing that would help to look at is the cam timing. Are they the same, are the flanks the same? You could advance the cams 4* (if you have room) which would pick up bottom end and mid range but not over all peak power. Though your max rpm would be a tad lower. Or advance the cams 4* for top end power. Just some simple tuning stuff to play with to see what works and what doesn't. Remember motors are dynamic power makers. Just because it looks good on paper (static) it just may not work in the dynamic world. Or visa versa.

So when are you going to get a dyno?
 

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To me it doesn't matter cause the bird has enough power to put that s#&t eating grin on my face all the time.:popcorn:
YEP, what he said.

RollinOn just fit on a throttle tube from an R1 to the BB as the outside diameter is bigger and that grin will become quicker. lol!
Everything is quicker here in Texas.:)
STex, out
 
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