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.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)
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).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.
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.
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!VIN plate states 90dba at 4750rpm
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.RC46, apparently I didn't give the "wanted" answer so I am wrong lol.
So even if we multiply 7 (122-115) by 1.2, we are no where near 12, let alone 20 hp :nono::eyebrows: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.
Bold text, post number 13.No one has contested your answer, or did I miss something?
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".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.
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.
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:
I never said it had that, I said it felt like it. (disclaimer: my butt is not calibrated lol).we are no where near 12, let alone 20 hp :nono::eyebrows:
you completely forgot about the flux capacitor spooling up!! :rotfl: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)
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.*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
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.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.
YEP, what he said.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.opcorn: