Kawasaki Versys Forum banner

1 - 17 of 17 Posts

·
Registered
Joined
·
100 Posts
Discussion Starter #1
So quick question, but what are the advantages and disadvantages of the paralell twin vs. a V-twin vs. an opposed twin? It seems that the paralell twins are buzzier and put your feet to sleep where the V-twins are more gentle. Is this just a lack of expeirence on my part or are there other reasons to use a V, opposed, or paralell in a bike?
 

·
Registered
Joined
·
466 Posts
90 degree V-twins have perfect primary balance; the further from 90 the more vibration(think Ducati versus Harley). Incidentally, Ducati do not call their engine a V-twin, they call it an L-twin to differentiate it from a V-twin of any other angle than 90 degrees.
An opposed twin such as a BMW (assuming that the crank throws are 180 degrees apart) is also a design that has perfect primary balance. An inline 6 cylinder engine is another example.
A parallel twin is one of the worst engine configurations for primary balance.

HOWEVER: (there is always 1 isn't there)
Most engine designs include balancers to at the very least remove some of the secondary engine vibration. Note: there are also third, forth, fifth, etc. vibrations that are induced by other moving parts such as values opening and closing, etc.) One of the biggest sources of secondary vibration is when the crank throws are not in the same plane. This is why Harley use a knife & fork arrangement.

Summary: Any engine can be designed to have a lesser amount of vibration so there is no such thing as an absolute answer to your question, there are just two many other elements to take into account.

A motorcycles vibration level can also be reduced by such things as rubber mounting of he vibrating components.

When any engine produces vibration it is reducing the amount of power output due to the fact that power is required to make it vibrate so if it were possible (it isn't) to make 2 identical engines except for the crankshafts the one with the best balance would produce the most horsepower.
 
4

·
Guest
Joined
·
0 Posts
for a volume manufacturer? - cost is a big part of the equation. A V twin has two of everything, heads/barrles/cams etc etc. Also its a relatively long engine, albeit narrow (but so is the V lump) A 90 degree twin tends to dictate a shorter swingarm, can have clearance implications to front wheel. All this that dictates frame geometry/airbox volume/packaging and so on.

Duc's/Aprillia reduce thier V angle to compensate somewhat.
 

·
Registered
Joined
·
687 Posts
There are some real advantages to the parallel twin configuration: packaging simplicity and mass centralization are two that spring to mind. The tradeoff is increased primary vibration, which Kawasaki has addressed (pretty successfully) with counterbalancers.

A big disadvantage of the boxer layout is crappy ground clearance when strafing corners. IMO the boxer engine is outdated. It made sense back in the day of air cooling, to have each cylinder sticking out in the breeze like that. Not any more though. There are better ways to package an engine.
 

·
Registered
Joined
·
234 Posts
Duc's/Aprillia reduce thier V angle to compensate somewhat.
Every recent Ducati twin of which I am aware has a 90 degree angle between the cylinders. Which Duc is this?

Yeah, the Aprilia twin made by Rotax is a 60 degree twin, IIRC, the SXV twin is 77 degree, and the Shiver/Dorsoduro is back to 90 I think.

I think Pegasus did a good job of laying out some of the classic trade-offs.
 

·
Registered
Joined
·
1,063 Posts
I'll take a stab at this because I've ridden both extensively, with two suzuki's - the SV and the DL, and now the versys. But not from a scientific point, more of a feel.

A v-twin makes power differently. It has low end torque, or grunt if you will. They pull stronger from a lower rpm and they have a lower peak rpm.

They are easy to short shift, they are smooth to ride, and they make a different sound.

The differences are subtle though. I was surprised how similar rather than how different my versys is compared the DL1000. Sure, the bigger bike made more power and had a higher top speed, but the torque and performance are similar. They do vibrate but differently. I recall early DL's shuddered so bad at about 3K rpm that it blew out some clutches. Some owners were not very happy with it. Keep it revving though and it runs fine. Gee, does that sound just like the versys?

In fact that's my solution for anyone that thinks the versys vibrates. Keep the revs over four grand or so and it's pretty darn smooth. It is definitely a revvy motor.

The parallel is a little simpler and a little more compact. To me they are either an outgrowth from a thumper or a paring down of the magnificent parallel 4's. We get a very high performance little mill in the versys, much smoother than a thumper with the peak performance of a multi-cylinder. The bane of the thumper is vibration, as is the narrow vee you find in the HD.
 

·
Registered
Joined
·
434 Posts
Even parallel twins have some variations that introduce different interesting results, such as the Triumph Bonneville and the new Yamaha Super Tenere 1200. Both are parallel twins in which the power strokes are 270 degrees apart and become quasi-cousins of big singles.

V-Zee
 

·
Registered
Joined
·
234 Posts
Even parallel twins have some variations that introduce different interesting results, such as the Triumph Bonneville and the new Yamaha Super Tenere 1200. Both are parallel twins in which the power strokes are 270 degrees apart and become quasi-cousins of big singles.

V-Zee
I think the Bonneville is a 360 degree twin, unlike the Versys' 180. It's the Scrambler that is 270 degree, as is the new Super Ten, as has been the TDM for some time. The point of the 270 parallel twin is to mimic the firing order of a 90 degree V-twin. In fact, the TDM was originally a 360 degree twin, and when its road focused sibling, the TRX was introduced, Yamaha made it a 270 degree twin to emulate the exhaust note of a Ducati. If anything mimics a single - except twice as often - it's the 360 degree parallel twin with its firing order that is evenly spaced 360 degrees apart.
 
4

·
Guest
Joined
·
0 Posts
Every recent Ducati twin of which I am aware has a 90 degree angle between the cylinders. Which Duc is this?
duc on the brain, was just reading about a duc v8! - I meant "Ktm" - rc8 I beleive. prob a lot of other weird angles out there too.
 

·
Registered
Joined
·
434 Posts
I think the Bonneville is a 360 degree twin, unlike the Versys' 180. It's the Scrambler that is 270 degree, as is the new Super Ten, as has been the TDM for some time. The point of the 270 parallel twin is to mimic the firing order of a 90 degree V-twin. In fact, the TDM was originally a 360 degree twin, and when its road focused sibling, the TRX was introduced, Yamaha made it a 270 degree twin to emulate the exhaust note of a Ducati. If anything mimics a single - except twice as often - it's the 360 degree parallel twin with its firing order that is evenly spaced 360 degrees apart.
Actually, the Bonneville Scrambler also fires at 270 degrees.
 

·
Registered
Joined
·
100 Posts
Discussion Starter #12
So to summarize the basic points, I'm getting this:

Paralell twin:
Pro: higher rpm range
Con: most vibration

V-twin
Pro: narrow profile, lower end torque
Con: low rpm range, louder

Opposed twin
Pro: lowest vibration, easier to maintain due to accessibility
Cons: highest damage potential if laid over, lower hp to cc ratio


Does that sound about right in general terms?
 

·
Registered
Joined
·
466 Posts
No, I think it should be more like this:

Parallel twin
Pros:
Cheapest to manufacture
Smallest configuration for centralized mass
Cons:
Requires counter balancer and/or rubber mounting to reduce vibration

V-Twin
Pros:
Narrow profile
Cons:
Requires counter balancer and/or rubber mounting to reduce vibration

L-Twin
Pros:
Perfect primary balance
Cons:
May require counter balancer and/or rubber mounting to reduce secondary vibration
Difficult to design chassis, shorter swing arm

Opposed Twin
Pros:
Perfect primary balance
Cons:
May require counter balancer and/or rubber mounting to reduce secondary vibration
Larger frontal area / foot control placement

So there are no rules you can use to compare the types, they all have certain inherent advantages and disadvantages. Each design of each type will be total different. The only thing you can do is to compare 2 engines and the package they are enclosed in. For example two V-Twins engines will be completely different in power, vibration, character, torque curve, and sound.
Think Aprila versus Harley; both have the same engine type. One has a red-line of about 5500 RPM, shakes like a cement mixer, makes about 60-65 HP, is heavy, handles like a school bus, but looks real pretty and the girls love them. The other has a red-line twice as high, is relatively smooth, makes twice as much HP, handles fantastic, is lighter, for all except a few models is half the price, is beautiful and makes other riders envious. Which do you like? Depends upon your wallet, whether you like to hang out at bars and pick up girls or enjoy riding the curvy roads.

Do not be hung up on engine configuration type as a qualification in and of itself. Compare two motorcycles as a whole for how well they fit your own criteria. This is why the Versys won 2008 motorcycle of the year. It was (and is in my humble opinion) the best all around package dollar for dollar that you can buy. Here is another example for you. Yamaha’s new cross-plane 4 cylinder inline engine has completely different sound, torque characteristics, etc. than any of the other Japanese inline 4’s.
 

·
Registered
Joined
·
295 Posts
There are some real advantages to the parallel twin configuration: packaging simplicity and mass centralization are two that spring to mind. The tradeoff is increased primary vibration, which Kawasaki has addressed (pretty successfully) with counterbalancers.

A big disadvantage of the boxer layout is crappy ground clearance when strafing corners. IMO the boxer engine is outdated. It made sense back in the day of air cooling, to have each cylinder sticking out in the breeze like that. Not any more though. There are better ways to package an engine.
how about the moto guzzi displacement for ground clearance.?

they never built a powerhouse though
 
1 - 17 of 17 Posts
Top