vmax vs hayabusa

[larra]

rapid magazine states that the new vmax outaccelerates hayabusa
by such a margin in the straight line that even on a race track despite hayabusas superiority in the twisties the new vmax reels it in on straights. but if vmax is such a weapon in the straight line, how come all the comparisons i have seen, show the new vmax trailing hayabusa by at least .5 seconds and by about 10 mph in the 1/4 mile.so i think it is all about the seat of the pants feeling,the fact is that the stop watch does not lie but vmax is soundly beaten by busa as well as b-king.
v-max is a powerful bike but unless it comes up with times to prove otherwise its still not the straightline king at all, period.

[simmo]

rapid magazine states that the new vmax outaccelerates hayabusa
by such a margin in the straight line that even on a race track despite hayabusas superiority in the twisties the new vmax reels it in on straights. but if vmax is such a weapon in the straight line, how come all the comparisons i have seen, show the new vmax trailing hayabusa by at least .5 seconds and by about 10 mph in the 1/4 mile.so i think it is all about the seat of the pants feeling,the fact is that the stop watch does not lie but vmax is soundly beaten by busa as well as b-king.
v-max is a powerful bike but unless it comes up with times to prove otherwise its still not the straightline king at all, period.

Should be good at the drags then with more power & weight yeah right

[bigjay]

From what i understand the only thing that hurts the vmax is the top speed restriction. 220 or 230 i think. In stock trim it actually does out accelerate a busa and the bmw 1300 in any gear standing start or roll on. Just doesn't have the top speed capabilities. Before anyone gets angry, its just what i read....

[Tony Nitrous]

In back to back test's, same conditions, same rider, same track,
the Max normaly loses to the B-King.

Cycle magazine in the US used a prep'd track, and top rider etc and still
couldnt get a Max down to BK times.

Seen a couple of BK's and Busa's beat by Max's at Willowbank but normaly
due to better riders.

[daaef]

The major other thing that hurts the vmax is aesthetics and the price...!

[larra]

From what i understand the only thing that hurts the vmax is the top speed restriction. 220 or 230 i think. In stock trim it actually does out accelerate a busa and the bmw 1300 in any gear standing start or roll on. Just doesn't have the top speed capabilities. Before anyone gets angry, its just what i read....

So far i have not heard of any stock vmax hitting its top speed in 1/4 mile so that is not an issue..

"outright top speed is governed to 137 mph, the black boxes have been programmed to recognize a dragstrip-style blast through the gears and in that case allow an extra 6 mph—but only for a quarter-mile. Taking that 143 mph "
It also loses out in 0-60 foot times as well as 1/8 mile times. I also understand that it is geared a lot higher than b-king or busa and that may make it quicker in some gear to gear comparisons..

[Maj]

Ev rode a Max at speedweek in the US, Production class, totally stock except the steering damper that had to be fitted for the event , from the scta records
P-P Evelyne R. Scholz Yamaha 8/09 165.377 ,
Thats mph , and a 2 way average

[playswithnitro]

Hey Larra,

Read it again carefully.

"Rolling on from any gear at any rpm and the VMAX simply leaves the K1300S and Busa for dead."
That's real world road riding experience. We were not testing performance over a measured distance from a standing start.

Let me quote myself...
"In fourth gear roll-ons from both 60 and 100km/h, the VMAX ran away from a K9 Busa. That was with my 120kg aboard the VMAX and a 100kg rider on the Busa. Not one but repeatedly." Mick on the max, page 34, Rapid Bikes, November 2009.

I was one of the irresponsible bastards for that particular exercise.

I have no reason to favour one brand of bike over another. What I wrote was my honest findings.


As far as drag racing is concerned, reasonably good riders have run 10.1 second ETs on stock standard VMaxs here in Australia.
The quicker ET between a VMax and a Busa will be recorded by the better rider. They are that close together.
A rider of average ability will find it easier to run a quicker ET on the VMax than they will on the Busa. The single biggest problem for drag racing a new VMax is wheelspin.

Have fun,
Mick 'Playswithnitro' Withers

[NEMESIS]

I love v max's.

Wayy too cool of a bike.
Price yeh its expensive,but thats what you pay
for exlusivity ;)

[Crane]

...
Let me quote myself...
"In fourth gear roll-ons from both 60 and 100km/h, the VMAX ran away from a K9 Busa. That was with my 120kg aboard the VMAX and a 100kg rider on the Busa. Not one but repeatedly." Mick on the max, page 34, Rapid Bikes, November 2009.
...

What sort of rpm were both bikes doing during that test? Comparable? Is it worth mentioning if the rev ranges were significantly different?

I guess you were testing bikes out of the box eh.

I just mention it because I have seen humungous arguements about performance stats where the two vehicles in question weren't set up in a comparable way with their gearing.

[1300hayabusa]

Im not sure about all these tests and how acurate these are when you consider that the Japs test their bikes with a rider who is no more than 60/5 kilos in weight,suspension and the rest of the shit is tuned to his specs and ultimately test runing on a decent track.I was told by a Japanese friend of mine that 80 kiols + could be classified as being a fat cnut in Japan,so all the little adds and offs would make a significant altered result than the one published.If I spend the same ammount of money on a busa as I would on a vmax I would have a rocket on wheels with all the goodys and left with change.This vmax is the hardly davidson of the jap market when it comes to price and its all a matter of what one is happy spending.I dont think that comparing it to a busa or bking is correct cause price and style are oceans apart!!!!
I went to mount glorious a few weeks back and I caught up with this bloke with a new max.He was maybe 20 meters in front of me when I put on my high beam and he knew it was on...........his rolling accelaration was quick and it does have grunt but a few klang klang klangs later in the gearbox I went past him like a breeze!!!!!!Its all a matter of who is behind the bars cause Im sure that if the bloke on the vmax was a better rider,pushed a bit harder or more experienced Im sure that it would have been a leveld outcome.

[larra]

As i said vmax is geared higher and has heaps of low down torque and i would be surprised if 60-100 roll on went to a busa, but each bike has its sweet spots and busa's starts at 7000 rpm -all the way to the redline.. and my bet is that from 7000-on busa walks away from vmax.

[busakid08]

Street cred ...............Busa kills it :)

My wife likes the Vmax though ...bugger .... must be a chick thing, if it looks blingy and bright must be good bike - bit like a spewkatti ha ha ha

Guess the only way to solve it is own both bikes and enjoy both :)

[Camel]

So. Why does the VMax have gobs of low down torque and out accelerate the Busa?

When it first came out I was intrigued by this so I read up everything I could find on the new engine. It has a number of nice features, but I think the killer here is the variable length intake manifold.

Remember the EF Falcon? It caned the EB/ED Falcon despite being almost the same engine. The difference was the variable length intake manifold. I was working for a quasi government body that was acting as a clearing house for the Aussie car manufacturers back in the mid 90's. This clearing house was established to distribute new and/or test cars and components to TAFE colleges. Ford did a lot of work on the manifolds to get it right, I know because I was able to pull apart all their prototypes! Many car manufacturers now use variable length manifolds because they're simple and effective. But you don't see them on bikes much because they take up room.

Yamaha has got it right. They actually seem to have perfected the theory in applying it to a bike. Some people on the forum here have played with 'bellmouth' lengths and have noticed a difference. Basically, a longer narrower bellmouth provides more torque because it keeps the airflow through the throttle bodies high and helps assure good cylinder stuffing. But as your engine speed rises these long bellmouths become restrictive and choke the engine. Conversely, relatively short bellmouths cause problems at low rpm because the airflow rate is low and you can't get good atomisation of fuel. A simple example of this when you are running carbies on a big-bore road bike and take the airbox and bellmouths off; you can see 'fogging' and petrol spitting back out the carby. The engine is basically 'gulping' air from the area closest to the back of the valve and not getting a good fuel air mix stuffed into the cylinder. However, as engine speed rises so does the airflow down the inlet tract and as a result so does power.

The best of both worlds is to have an inlet manifold that can change from long bellmouth to short bellmouth. Which is what Yamaha have done. The inlet manifold is much more refined that the old Falcon' and car designs (thank fcuk). It actually is a bellmouth shape, or rather two, one which fits inside the other for each throttlebody. At low RPM the upper, narrower bellmouth sits snugly inside the lower, wider bellmouth. At 6.800 rpm (thereabouts) the upper bellmouth is moved up about 2 cm to allow air to flow through the gap between the two. Actually, the design is so well done that the air flowing through the upper bellmouth creates a venturi effect which draws in extra air through the gap than would otherwise normally happen. Brilliant!

Brilliant and so easy to replicate. When I saw that the Gen II Busa had a programmable shift light I had a germ of an idea begin to fester in my noggin. If I could wire in a relay to run off the programmable shift light then I could use that relay to power a stepper motor to run a variable length inlet manifold on my Busa! Instant V Max killer!

Then I got involved in development of ECU Editor and found that there is an unused EXUP-type map already sitting in the Gen II's software......... EXUP is Yamaha's version of an exhaust valve which works similarly to the variable length manifold concept. Instead of increasing air flow to get torque it restricts exhaust flow to help stop the inlet charge coming straight out the exhaust (due to extreme valve overlap). Ideally you'd synchronise EXUP with a variable length inlet manifold to get a broader spread of power in an engine, but for the Busa I reckon the dual injector and throttle body setup could benefit further from a variable length manifold. Sure the secondary throttle plates are designed to increase airflow at lower revs, but the venturi effect mentioned above, plus the fact that bellmouths are far less restrictive than throttle plates (even when fully open) would make the variable length manifold a great power increasing proposition. That being said, I wouldn't remove the secondary throttle plates because they're essential for fuel atomisation (look at the angle the secondary injectors sit at).

There's all manner of secrets stashed away in the standard Gen II ECU.... Anyone noticed the traction control boss cast into their rear brake stay arm???

Camel

[NEMESIS]

So the gen2 has a list full of good hidden away in its computer!!??

Good stuff camel!