Sportbike World banner

1 - 20 of 21 Posts

·
Strength and Honor
Joined
·
6,144 Posts
The CF in the headlight section makes it look like a fly, which I personally don't care for but I really like the look of the street version :drool:
 

·
Registered
Joined
·
12 Posts
Discussion Starter #3
For me the street version is the hottest bike ever seen!! :jawdrop:

I cant wait to have a test ride on track with it! Actually i have it booked up for some date in february by Aprilia which is often offering these events in Italy to encourage people buying their motorcycles (they used to do that also with the older model RSV).
 

·
Strength and Honor
Joined
·
6,144 Posts
Eh, I'll take the 1098S over that, thanks.
 

·
Registered
Joined
·
1,207 Posts
I dig it.......besides, I dont like duck....:twofinger
 

·
Registered
Joined
·
1,346 Posts
Love it

Personally, I really dig that new Aprilia V4. And it's about time that somebody else besides Honda came out with a V-4 engine. Aside from it's complexity, I don't know why other manufacturers haven't adopted that design.- They're really torquey engines with a roarty engine sound but with the smoothness and top-end power of an inline 4.

Inject a little Italian soul, and you have a recipe for a really wonderful and unique bike.
 

·
Registered
Joined
·
8,798 Posts
2 reasons not to put a V4 in a sportbike.
1. Its larger front to back, leaving less room to move in in the frame, giving designers less control over CG
2. With two heads, its much more expensive than an inline. Manufacturers compete on price as much as performance.

I don't see right of hand why a V configuration would have any natural torque advantage over an inline. Yes, V twins often have better low ends, but that is because their two cylinders can't move as fast as the smaller 4, so they are tuned for low end. Unless I am missing something, an inline twin should have very similar characteristics to an V
 

·
Registered
Joined
·
12 Posts
Discussion Starter #13
You are missing something though.
The whole issue of that V4 engine is to compare it with a 4inline and get something better out, not with the "torquesly" V2s..
Now, a V4 takes obviously less space in the frame than a inline giving the constructors and engineers the chance to make a smaller frame and bike, so to make it be "faster" in terms of maneuverability improving (later) the performance of the engine that could make better then a V2 because heavyier like you before mentioned.
At least this is the goal of the whole project, we'll see what comes out.
 

·
Registered
Joined
·
8,798 Posts
a V4 is going to be larger in overall volume than an inline, not smaller. True, it will be narrower, but manufacturers got around that problem by running the frame spars over the engine, instead of around it. However, it will be much larger front to back than an inline.
A smaller front to back enigne can be hung in many ways in the frame. You can move it back and forth, you can tilt it, etc. Since the engine makes up a considerable weight of the overall bike, moving the engine around shifts the CG considerably, drastically affecting handling.
A longer front to back engine cannot be moved as far to the front or rear, limiting the CG options. It is narrower, and can be moved from side to side, but why would you want the CG further to the right or left? No, you want it right in the middle.
It does permit you to make the bike somewhat narrower, improving aerodynamics, which may result in a higher top speed. What is more important to you, handling or top speed?
 

·
Registered
Joined
·
1,346 Posts
Vash,

Some of the best handling bikes in the world have V-4 engine configurations. The MotoGP bikes from Honda, Ducati, and Suzuki all feature V-4 engines. That being the case, there must not be much of a disadvantage to this design from a handling perspective.
(although Yamaha, an inline 4 design, did take the 2008 championship)
 

·
Registered
Joined
·
12 Posts
Discussion Starter #16
Vash,

Some of the best handling bikes in the world have V-4 engine configurations. The MotoGP bikes from Honda, Ducati, and Suzuki all feature V-4 engines. That being the case, there must not be much of a disadvantage to this design from a handling perspective.
(although Yamaha, an inline 4 design, did take the 2008 championship)
:eyebrows::eyebrows::eyebrows:
 

·
Registered
Joined
·
8,798 Posts
The design limits options. It sounds like it has some advantage, but for the life of me I don't know what it is.
For ducati it was a natural move. They couldn't spin the twin fast enough, they can keep more of their proven design by going to a V, instead of starting from scratch with an inline.
I was under the impression that honda ran a 5 cylinder, and no idea on the suzi.

I would really like to know what the advantage of a V is. The disadvantages are clear to me.
 

·
Premium Member
Joined
·
3,449 Posts
Was Ducati using a V4 last year? Because Stoner walked all over everybody on the straights.

This year, Rossi was back on top of his game though, and there was no stopping him.
 

·
Registered
Joined
·
659 Posts
The design limits options. It sounds like it has some advantage, but for the life of me I don't know what it is.
For ducati it was a natural move. They couldn't spin the twin fast enough, they can keep more of their proven design by going to a V, instead of starting from scratch with an inline.
I was under the impression that honda ran a 5 cylinder, and no idea on the suzi.

I would really like to know what the advantage of a V is. The disadvantages are clear to me.
One advantage is reduced moment of inertia of the engine. Even if the center of mass and mass were the same between an inline and a V, the moment would be lower on a V because the mass is closer to its center. In addition, with the rear bank closer to the center of mass of the bike and only two cylinders out front, a V configuration probably contributes less to the overall bike moment of inertia. That might be enough to counteract its potentially higher cg. Of course, this entire discussion is pure conjecture without comparing actual engines and bikes. Depending on how each is mounted, a V-4 could actually have a lower cg than an inline.

Another advantage is that a 90 deg. V-4 does not require a balance shaft like an inline 4, reducing rotational mass.
 

·
Registered
Joined
·
8,798 Posts
If I understood you correctly, are you saying that the mass is more centralized side to side in a V engine?


Can you elaborate on the balance shaft?
 
1 - 20 of 21 Posts
Top