Talk:V-twin engine

V angles

I rearranged the content and synched with the "V-Twin or L-Twin" section of the Ducati V-twin Motorcycle article to achieve consistency in definitions across articles. I tried to make only minor edits to the original text and used existing content from the other wiki article. This is a restructure not a rewrite.

ADDED: Generally, any two-cylinder motorcycle engine with its two cylinders at an equidistant opposite angles from the center rotation of the crankshaft is referred to as a V-twin. FROM: "V-Twin or L-Twin" section of the Ducati V-twin motorcycles topic. PURPOSE: Consistency in definitions across articles.

MOVED UP: Reference to Harley 45-deg engine toward the beginning of the topic. PURPOSE: Better organization and clarity for readers.

MOVED DOWN: Discussion of 90-degree L-twin engines. PURPOSE: Better organization and clarity for readers.

RETAINED: Two S&S engine references. They really should be deleted. There are a number of other engine-only manufacturers and none of them are listed here.

RETAINED: The entire article has a motorcycle bias. Where is the Briggs & Stratton Vanguard V-Twin Horizontal Engine? Kohler, Husqvarna, John Deer?

RETAINED: The 90-deg counterweight note seems odd in this topic but I retained it as I am attempting a restructure not a rewrite.

DELETED: Indian from the list. I searched on wiki, on the Indian website, and did a general web search and could not find the v-angle for the Power Plus 105 engine - the only engine currently manufactured by Indian. Is this reference to the defunct original Indian or the bankrupt Gilroy Indian? If so, it would be equally odd to include Excelsior-Henderson in this list. Why is this reference even here? Certainly, the Victory division of Polaris is better know and has higher production volume than Indian which is a limited-production or "boutique" manufacturer. PURPOSE: References to defunct, boutique, or low-production manufacturers would be rather obscure for the average reader.

Groovymaster (talk) —Preceding undated comment added 21:11, 18 October 2009 (UTC).

moved: the specific engine references into a table

added: references

Sandersjoshua (talk) 11:35, 19 April 2010 (UTC)

The Zündapp KS 601 is listed in the chart as having a 170-degree v-twin engine. AFAIK, that model has a horizontally-opposed 180-degree, or "boxer" engine. Bricology (talk) 22:14, 28 September 2014 (UTC)

You might be right. The KS750 had the angle narrowed to 170°, but I don't know about the KS601. I've changed it to KS750. Sincerely, SamBlob (talk) 23:51, 28 September 2014 (UTC)

Torque reaction due to longitudinal mounting

"...slight disadvantage of causing a torque reaction that tends to lean the motorcycle slightly to one side..."

Any reference for this? Any idea how big this torque is, or how much of a "disadvantage" it is?

This should also be an issue for boxers and big flat sixes like Goldwings and Valkyries, right? The new Triumph Rocket III at 2300cc should be the worst? Any reports of riders loosing countrol or complaining about this issue?

Didn't some cable show actually warn about the "dangers" of longitudinally mounted v-twins? Is this just hype from Harley buffs for why that configuration is superior? -AndrewDressel 01:29, 12 October 2006 (UTC)

- It appears to match almost word for word the claim made on http://www.hogsandparts.com/history/vtwinhistory.htm, a Harley specific site.

- It is also matches word for word http://experts.about.com/e/v/v/V-twin.htm and http://vtwin.quickseek.com/. Hmmm, who's copying whom?

After all, it is only the crankshaft and some fraction of the connecting arms that rotates, right? That accounts for only a fraction of the total weight of the bike and has a pretty small radius. - AndrewDressel 04:19, 12 October 2006 (UTC)

Personal riding experience bears out a torque reaction, especially under hard acceleration, when riding longitudinal or "flying" v-twins, as well as older BMW flat twins and some inline bikes where the cylinders are in line with the frame. (I don't know about newer BMWs.) It is quite noticeable at times but minor in that I can't imagine it would ever cause any but a very new rider to lose control. It can be a bit startling the first few times it is experienced, and makes the bike feel much less refined. If you were doing quarter mile runs, it might also get quite distracting and diminish your performance.

Many motorcycle reviews mention whether or not torque reaction is present in a given bike.

Goldwings and many other bikes have corrected for torque reaction by rotating the transmission gears and/or the balance and drive shafts opposite that of the crankshaft so that there is approximately equal mass turning clockwise and counterclockwise at any time, thereby physically canceling the effect.

An excerpt from a review of the Triumph Rocket: "The 120-degree crank spins one way, while the balance, transmission-input and final-drive shafts all spin the other, mostly counteracting vibration and torque reaction. In neutral, you can feel the bike try to roll slightly to the right with each throttle blip, but the effect is not nearly as strong as a BMW's."

Google "motorcycle torque reaction" if you'd like more information; there's a lot out there. If you want an extreme example, there are bikes powered by small block Chevy 350 V-8s (Boss Hoss Cycles) that have scads of torque reaction, and I've seen a video clip on the net that demonstrates it quite clearly. I've also seen one twist like that in person.

Hope this helps. Unfocused 03:19, 1 November 2006 (UTC)

Very much. In fact, I pasted your entire 3rd paragraph into the article. I hope you don't mind. I actually have a Guzzi, and while I can notice when stopped at a light, it hasn't been a factor for me while riding. Perhaps I'm too casual. -AndrewDressel 19:53, 1 November 2006 (UTC)

Its quite normal that the article matches word for word sites using GFDL Wikipedia content. For the other site well I don't know but I think a lot people have written something like "A molecule of water is made of two atoms of hydrogen and one atom of oxygen." or "Bob Dylan is a famous songwriter" without copying each other. Ericd 06:01, 1 November 2006 (UTC)

So long as it is not just propagating a myth. -AndrewDressel 19:53, 1 November 2006 (UTC)

Transverse vs Longitudinal

On 18 November 2006 at 14:58 User 151.205.153.207 swapped transverse for longitudinal and vica versa throughout the article. Specifically, Harley Davidson's orientation is now called longitudinal, and Moto Guzzi is now called transverse. These terms appear to be poorly defined.

On the one hand dictionary.com defines 'transverse' as "(of an automotive engine) mounted with the crankshaft oriented sideways".

On the other hand, BMW, on its web site, refers to its boxer as having "transversely mounted cylinders".

Perhaps the confusion comes from the terms transverse and longitudinal being used to describe either the crankshaft orientation or, contradictorily, the cylinder orientation (the latter only making sense in the case of v-twins and boxers, I guess).

So, a Harley's crankshaft is mounted transversely, and its cylinders are mounted longitudinally; and a Moto Guzzi's and a BMW boxer's crankshaft is mounted longitudinally, and its cylinders are mounted transversely.

Searching with google for any manufacturer and the words transverse or longitudinal returns thousands of hits. There does not appear to be a reliable convention for whether the terms transverse and longitudinal by themselves refer to the crankshaft or the cylinder orientation in motorcycles. Does anyone have a definitive source this article can reference?

In the meantime, I've added a clarification at the beginning of the section. -AndrewDressel 17:54, 20 November 2006 (UTC)

On 10:14, 24 December 2006, user 213.216.199.30 said "Orientations - Changed the description to use crankshaft orientation as now it is in line with orientation mentioned in Honda ST series wiki pages" and went on to change the article to read "The terms longitudinal and transverse are used to refer to the crankshaft orientation. A common mistake with V-2 engines is to refer to the cylinder orientation (as mentioned on BMW's web site). However referring to the crankshaft gives a correct method to engine orientations as it gives the same orientation for all V-engine types like V-2, V-4 (which would be difficult to describe with cylinder orientation) and V-8."

Sounds good, but are there any confirming references?-AndrewDressel 13:28, 24 December 2006 (UTC)

None that I know of. You had the definition from dictionary.com. I have seen no better definitions. 213.216.199.30 09:43, 31 December 2006 (UTC)

I know that this is a very common issue to fight about and make a mistake. Think about single cylinder engines. How do you tell if they are transverse or longitudinal. By crankshaft. Think about Dodge Tomahawk with V10, definetly longitudinal. Remove two cylinders. Boss Hoss V8, longitudinal. Remove two. Nonexisting V6, must be longitudinal. Remove two, Honda ST V4, this is a difficult one, but longitudinal accoring to wiki and longitudinal according to this reasoning written here. Then remove two cylinders. Moto Guzzi. Did we turn the engine while removing those cylinders? No, so this must be longitudinal as well. 213.216.199.30 09:43, 31 December 2006 (UTC)

Sorry to reopen this can of worms, but I have several reliable sources that take both opposite positions on this question.

Some go by the crankshaft, and some by the cylinders. Some are unclear as to which they mean. A Moto Guzzi Technical Services representative told LA Times reporter Susan Carpenter that Moto Guzzi engines are "called 'transverse' because the engine is mounted with the crankshaft oriented front to back instead of left to right." The BMW history quote above is the only one I'm aware of that actually calls it an "error" or "misconception." Wikipedia should not be taking sides in this, but rather should only inform readers that experts disagree about this terminology. Further, while I agree that it makes the most sense to go by the crankshaft, and that the article should be organized that way, we should explicitly say so by changing the headings from Transverse Mounting and Longitudinal Mounting to Transverse Crankshaft Mounting and Longitudinal Crankshaft Mounting.

I'm going to gather up some sources and change the article to state that this is a subject of disagreement, unless somebody wants to object. If the BMW source is gone forever I'll have to remove it, but hopefully it can be found somewhere.--Dbratland (talk) 21:44, 29 April 2009 (UTC)

Nice job pulling up the sources. Using the crankshaft plane makes the most sense to me, and you've got sources to back it up. Though it looks like some of the confusion is the difference in terminology with cars vs bikes? I mean, transverse in a bike means the jugs stick out, like a Guzzi, while transverse in a car means the crankshaft is "across", like an inline 4 front wheel drive? tedder (talk) 21:48, 29 April 2009 (UTC)

The LA Times reporer said she thinks it is a cars-vs-motorcycles thing. But Darwin Holmstrom, for example, coauthored a book about BMW where he went with the crankshaft, yet he wrote in the Idiot's Guide that Moto Guzzis are transverse, going by the cylinders, not the crank. Other motorcycle sources go both ways too.--Dbratland (talk) 21:56, 29 April 2009 (UTC)

• Uses explicit mention of crankshaft to avoid ambiguity: Cocco, Gaetano (2004), Motorcycle design and technology, p. 118, ISBN 0760319901, 9780760319901, V-twin with transverse crankshaft: [...] twin-cylinder with longitudinal crankshaft: [...] If the engines' crankshaft is longitudinal, it is well-suited to shaft-drive transmission {{citation}}: Check |isbn= value: invalid character (help); Text "publisher MotorBooks/MBI Publishing Company" ignored (help)--Dbratland (talk) 04:37, 1 May 2009 (UTC)

• Done.--Dbratland (talk) 22:11, 1 June 2009 (UTC)

Cooling

Thanks Jeff for the reference, but it actually confirms my suspicion. It is comparing flat twins to transverse mounted v-twins, not the longitudinal V-twin of which the flat twin is being described as the ""logical alternative". I would argue that most longitudinal V-twins run nearly as cool as their 180° opposed cousins. I'll look for a source. -AndrewDressel 04:49, 20 February 2007 (UTC)

Well, it looks like we've gotten that straightened out. -AndrewDressel 16:40, 20 February 2007 (UTC)

True V-twin vs V-2

The Complete Guide to Motorcycle Mechanics, a text book from the Motorcycle Mechanics Institute (1984, Prentice-Hall, Inc., ISBN 0-13-160549-6) does not make this distinction. See page 61. Also, parallel-twins don't share a crank pin, and yet they are not called "Parallel-2s." Unless someone can come up with a good citation for this distinction, I think it should be struck. -- Pi3832 04:54, 3 March 2007 (UTC)

I concur with this suggestion. Cite it or strike it. Respectfully, SamBlob 12:09, 15 June 2007 (UTC)

I edited this with "common misconception" wording which perhaps should be removed since it's not all that common, and it's a matter of either opinion or original research. People who make the distinction seem to be the same ones who believe that "V-twin" is a Harley-Davidson trademark and/or invention. Real Deuce (talk) 00:46, 21 May 2008 (UTC)

Aha! Figured it out. The Boxer engine is often differentiated from a "180 degree V" engine using the crank pin layout. Added an explanation of this. The reasoning behind the differentiation is that some of the characteristics of the dual offset crank pin engines are not shared with the more common V design and are instead shared with the boxer engines. However, differentiating using "twin" vs the number two completely fails to convey this. I can't find a reference to any other verbal shorthand for differentiating between the two layouts though, so it appears that while it is a source of misunderstanding, it does have some usage history behind it. —Preceding unsigned comment added by Real Deuce (talk • contribs) 08:23, 16 June 2008 (UTC)

Nicely done. After going back and forth for a while, these things often boil down to "some people call it A, and others call it B". Wikipedia is the only venue I know for getting to the bottom of issues like this. -AndrewDressel (talk) 14:13, 16 June 2008 (UTC)

The header to the https://en.wikipedia.org/wiki/V-twin_engine is incorrect. It says "A V-twin engine, also called a V4 engine, is a four-cylinder piston engine where the cylinders share a common crankshaft and are arranged in a V configuration." A V-twin is a two cylinder, not a V4. This cannot be edited.

Filling list up with non-notable content

WP:NOTDIR states clearly that Wikipedia is not a directory, not a collection of long lists of information, yet in this edit that is exactly what is happening. By all means list engines which have articles on Wikipedia, but where neither then engine manufacturer nor the vehicle have an article there should be no place for such content. If the company and/or engine is notable then write the article first. --Biker Biker (talk) 15:20, 5 September 2010 (UTC)

WP:IL is used to prove notably. Sandersjoshua (talk) 15:39, 5 September 2010 (UTC)

Interwiki links go at the bottom of a page, not as inline links. --Biker Biker (talk) 16:23, 5 September 2010 (UTC)

Drysdale Godzilla V2

According to an article in http://www.mcnytt.se/hem/drysdale-godzilla-1840cc-vtwin-monster-mash-2118 , there seem to be severe mechanical limitations to traditional V2's, in regards to the revolutions per minute it allows. Tradiional cruisers (ie harley davidson's) are hence unable to make allot of RPM. "Metric cruisers" (mostly Japanese brands) have regular side-by-side bearings, and do not have this limitation. Drysdale appearantly solved this issue with the Godzilla V2, by using a system similar to 1930's Mercedes Benz racing cars.~He worked together with Tony Foale on this.

Mention in article. 91.182.194.4 (talk) 09:13, 14 October 2011 (UTC)

Why don't you write an article about the engine? --Biker Biker (talk) 11:01, 14 October 2011 (UTC)

Two-cylinder engine as parent page proposal

The following discussion is closed. Please do not modify it. Subsequent comments should be made in a new section. A summary of the conclusions reached follows.

The result of this discussion was No merge of this article is being considered.

---

Hi,

I put a "portion to be merged" tag at this top of the page as it seemed to be the closest tag to use for the job.

The intention here is to resolve a problem that has arisen relating to the three main groups of 'non-V' or 'non-flat' twins, i.e. transverse or parallel twins, inline or longitudinal twins, and tandem twins.

At present all three are being shoehorned into a single article called "Straight-two engine", which I argue is a far more obscure and minor terminology for some engine configurations, and not used widely by manufacturers. The previously unreferenced topic was started by a non-native English speaker, sometime ago. The preponderance of references suggests this does not meet Wikipedia naming conventions, as per WP:NAME; Recognizability, Naturalness, Precision, Conciseness, Consistency, English language use etc.

No changes to V-twin engine are being suggested whatsoever. Only a short introductory paragraph and, perhaps, image gallery relating to the configuration be included at Two-cylinder engine "master page" for all configurations.

Thank you. --Bridge Boy (talk) 18:49, 14 July 2012 (UTC)

• Discussion is not here. Discuss at Talk:Straight-two_engine#Merger_proposal. --Dennis Bratland (talk) 19:16, 14 July 2012 (UTC)

There being "no changes...being suggested whatsoever" to this article, I shall remove the "partial merge to" tag, which was mistakenly misused by the proposer. Sincerely, SamBlob (talk) 17:07, 15 July 2012 (UTC)

The discussion above is closed. Please do not modify it. Subsequent comments should be made on the appropriate discussion page. No further edits should be made to this discussion.

V2 as a tank engine

Most (if not all) soviet WW2 tanks used large V2 engines. GMRE (talk) 14:51, 13 April 2013 (UTC)

You're probably looking for this: Diesel model V-2. Despite the model name, the Diesel model V-2 is actually a V12 engine. Not even the Russians would make a 38 litre V-twin engine. Sincerely, SamBlob (talk) 15:18, 13 April 2013 (UTC)

I have made the hatnote of the article a bit clearer in that regard. Sincerely, SamBlob (talk) 15:31, 13 April 2013 (UTC)