Difference between "Inline Twin" and "Parallel Twin"?

[aargee]

So you guys saying Ninja 250R is a inline & not a parallel twin? If that were the case, then I guess we should file a case against Kawasaki & Bajaj for claiming the product to be something else instead of the reality & probably we could win a brand new Ninja for free.

[cool_dude_sunn_y]

We should ask here:

http://www.xbhp.com/talkies/desi-bikes/12801-long-term-plan-cbz-250r.html

On page 2, the valve pics show the valves of the 2 cyls in different positions...perhaps that makes it inline?

Yup .. Ninja 250R is Dual Inline

[cool_dude_sunn_y]

So you guys saying Ninja 250R is a inline & not a parallel twin? If that were the case, then I guess we should file a case against Kawasaki & Bajaj for claiming the product to be something else instead of the reality & probably we could win a brand new Ninja for free.

he he .. All the best dude

BTW .. Dual-Inline and Parallel Twin is the same. I guess you are confusing b/w V-Twin and Parallel Twin?

[aargee]

BTW .. Dual-Inline and Parallel Twin is the same. I guess you are confusing b/w V-Twin and Parallel Twin?

No I'm very clear in my understanding. If you look at the previous links that I've provided, none of them talk about V-Twins & pls do not bring V-Twins here to add confusions.

It started off with Parallel Twin & Inline Twin, then moved to Kwaker 250 being portrayed as inline twin or parallel twin; while the manufacturer says its parallel twin, its being claimed as inline.

Ok forget about Bajaj's probiking site, are you guys trying to say that Kawasaki is wrong even on this? -

[ken cool]

Moved Posts and Created Relevant New Thread

[tanay]

The confusion is caused by the word "parallel".


Taking the example of a 2-cylinder engine:

Most companies/people use "parallel" to denote the engine cylinders being parallel to each other in layout. This would differentiate it from the V-Twins or the Boxer engines.

But then, there is the usage of parallel to denote the actual pistons' position w.r.t each other. Here parallel denotes both pistons moving up and down simultaneously. The opposite here would be "inline" in which the pistons move opposite to each other.

Inline engines rev higher, parallel ones have good low-end torque.
Chris Pfeiffer's F800R is a parallel twin.

After a little bit of googling I read that there is also a general usage of the word "parallel". In this the cylinders are parallel and the pistons may move together or in an opposite motion.

Conclusion: It's all in the word. There may be specific labels like Dual-Inline and all but I guess we know the general idea.

I hope this clears up confusion.
I also hope this is correct in an overall perspective.

[aargee]

Ok, here's some clarification, the best I could come up with.
Parallel Twin - Notice the firing here; this is a good learning for me because, I was under the impression that the firing still happens at 360 (2S) or 720 (4S) on both the cylinders, but I learned that the firing is still halved even in parallel twin.

http://www.youtube.com/watch?v=LoCk4ai46lw

Inline Twin - Sorry that I couldn't find out one for twin cylinder; this is for four cylinders, but notice the firing sequence is same like parallel twin with the only difference being the movement of the piston.

http://www.youtube.com/watch?v=4vWoSXYnTa0&feature=related

[BOOO]

AFAIK, inline and parallel mean the same.

engines are either called big bang or screamer depending upon the firing order. They say screamers are more violent and difficult to control when compared to big bangs.

MotoGP : What is hidden behind fairings

[killer_instinct]

Ok, here's some clarification, the best I could come up with.
Parallel Twin - Notice the firing here; this is a good learning for me because, I was under the impression that the firing still happens at 360 (2S) or 720 (4S) on both the cylinders, but I learned that the firing is still halved even in parallel twin.

What changes in Torque and Power would be seen if both the cylinders are fired at the same time. Is this even possible?

Is the firing mechanism modifiable, if yes how would it affect the engine.

[aargee]

What changes in Torque and Power would be seen if both the cylinders are fired at the same time. Is this even possible?

Is the firing mechanism modifiable, if yes how would it affect the engine.

Oh!!! Boy, looks like you've seen only the last post of mine. Have you seen this post of mine? I myself have questions on this. Appreciate if someone can help me understand. Tks.

[Samarth 619]

What changes in Torque and Power would be seen if both the cylinders are fired at the same time. Is this even possible?

Is the firing mechanism modifiable, if yes how would it affect the engine.

yes, its possible... In fact, it used to happen earlier but it was abandoned due to no big usage benefit.
It used a 360* crank I talked about in the Technical terms thread.

The effects were the same as a single cylinder engine... Dhug dhug sound, torquey engine...

@ aargee- so you thought both cyls fired at once? So, thats what the confusion was about...

The equi-distant firing order makes Ninja 250 high revving, because its firing is equal gapped.

It is 360* - cylinder 1 fires - 360* - cylinder 2 fires...

Had it been inline with 180* - 540* or some other order, it would have made lots of noise and displayed strange torque characteristics...

Firing matters a lot.

[aargee]

@ aargee- so you thought both cyls fired at once? So, thats what the confusion was about...

Only the firing was a learning, otherwise, I'm clear about the movment of the pistons with the said difference above.

[maraque]

he he .. All the best dude

BTW .. Dual-Inline and Parallel Twin is the same. I guess you are confusing b/w V-Twin and Parallel Twin?

AFAIK, inline and parallel mean the same.

engines are either called big bang or screamer depending upon the firing order. They say screamers are more violent and difficult to control when compared to big bangs.

I have to agree with them. As far as my understanding goes, an inline twin and a parallel twin mean the same thing. That is, a twin cylinder engine with the cylinders in line or lining up with each other, or arranged in parallel, having nothing whatsoever to do with the relative positions of the pistons or the firing order, which the numbers 360/180 degrees denotes.
Same as when we say a Ducati engine is a 90-degree V-twin engine. but it is also called a L-twin because the placement of the engine in the chassis means that the cylinder arrangement resemble the letter "L", hence the term L-twin. But at the heart of it all it's still basically a 90 degree V-twin, just another additional term. And also to throw into the mix, BMW's famous straight-six engines, also called an I6 or inline-six motor.

Just bringing my bit into the discussion, my $0.02.

[aargee]

As far as my understanding goes, an inline twin and a parallel twin mean the same thing. That is, a twin cylinder engine with the cylinders in line or lining up with each other, or arranged in parallel, having nothing whatsoever to do with the relative positions of the pistons or the firing order, which the numbers 360/180 degrees denotes.

I'm not sure if you're saying this after watching the video. Haven't you observed the positions of the pistons movement?

Same as when we say a Ducati engine is a 90-degree V-twin engine. Just bringing my bit into the discussion, my $0.02.

Yes, add your contribution, but pls refrain from bringing V-Twins into this topic as they're entirely different from what is being discussed here.

[maraque]

My bad. I just meant to imply that it's a loosely applied term. That was my point of bring in the Ducati. And I can see the point of the pistons moving in parallel or in series to each other. Just that there's no specific term such as an inline or a parallel engine. At the end of the day they are both in a parallel/inline plane. Hope I got my point through, I didn't mean to contradict what you said. Just that those terms are vague. And Wikipedia is also not always 100% reliable.

If you can give any other proof that says so, I'll eat my words.