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BIKELAND > FORUMS > ZX-14.com > Thread: NHRA Pro Stock motorcycle qualifying NEW TOPIC NEW POLL POST REPLY
RICH CRAFT 1


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posted March 09, 2012 04:41 PM        
NHRA Pro Stock motorcycle qualifying

Psn Rider Vehicle ET Speed
1. Eddie Krawiec Screamin' Eagle/Vance & Hines 6.824 197.54
2. Andrew Hines Screamin' Eagle/Vance & Hines 6.843 195.14
3. LE Tonglet Nitro Fish Suzuki 6.894 192.93
4. Matt Smith Matt Smith Racing Buell 6.927 192.99
5. Steve Johnson Steve Johnson Racing Suzuki 6.939 191.57
6. Karen Stoffer GEICO Powersports Suzuki 6.969 192.19
7. Hector Arana Lucas Oil Buell 7.004 188.44
8. Shawn Gann Prana Z Racing Buell 7.009 190.89
9. John Hall Buell 7.012 188.89
10. Hector Arana Jr Lucas Oil Buell 7.025 189.12
11. Joey Gladstone Awesome Engines Buel 7.035 188.41
12. Michael Ray Star Racing Buell 7.035 186.85
--------- Not Qualified ---------
13. Scotty Pollacheck Buell 7.038 185.54
14. Jim Underdahl Suzuki Extended Protection Suz 7.043 190.00
15. Michael Phillips The Edge Suzuki 7.044 189.02
16. James Surber Kosman Specialties Buell 7.096 185.49
17. Anne Hansen Hansen Racing Suzuki 7.110 187.47
18. Redell Harris Harris Racing Buell 7.127 186.64
19. Wesley Wells Kendall Suzuki 7.150 187.36
20. Mike Berry MB Precision/LAT Racing Oil Bu 7.246 186.00
21. Justin Finley Next Level Racing Suzuki 7.658 157.43
22. Jerry Savoie Savoie's Alligator Farm Suzuki 8.289 111.75
23. Charles Sulivan Sullivan Drilling/Gann Speed 16.949 42.04

I don't know when NHRA is gonna wake up and realize the fairytale that they are trying to push over on the American public is not real! . When you have a 1930 motorcycle design that you are trying to sell people. This is what happens. the Harleys get a160 cubic inches , the
Suzuki get 107 that's up six from last year,but still not enough. and before you can say fast Busa! there ain't no Busa motors in Pro Stock motorcycle. They are all old-school motors. And guess who bills 99% of them, yes, Andrew Hines. that is the same Hines with the two bikes at the top of the qualifying chart. how would you like to have a 35% bigger motor, and build all of your competitors engines. I would be embarrassed to have a monopoly like this in a professional sport Like NHRA. But it looks like nobody really cares.

Ken



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Wheelie


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Old Man
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posted March 09, 2012 04:45 PM        
I think I know what two bikes will win.

wee

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RICH CRAFT 1


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posted March 09, 2012 04:55 PM        
they won the championship last year, the year before that they were so embarrassed about what was going on. They pull this kid LE Tonglet in about halfway through the year, and let him win the championship. And yes, that's the same LE Tonglet that you see qualified in the number three spot. maybe if it gets too embarrassing for them this year They'll let him win again this year. LOL

this looks a lot like professional wrestling. LOL

Ken


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Wheelie


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Old Man
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posted March 09, 2012 05:01 PM        
sounds like a fair race 160ci vs 104ci... maybe this will catch on in other drag racing

wee

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1badzx12r


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posted March 09, 2012 05:05 PM        
everybody got their class to run in.. this is the harley class
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RICH CRAFT 1


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posted March 09, 2012 05:37 PM        
no this is not the Harley class NHRA about five or six years ago handed the Harley guys, the rulebook and said write down whatever you think you need to when. and every year after that they have given them whatever they wanted. They said because it's a pushrod motor. They need the break, but the pushrod they use is only 1 inch long. LOL. There has been a long list of rule changes through the years, but they always make sure the Harley stays on top.

Ken
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JZX


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posted March 09, 2012 05:45 PM        
NHRA prostock bike is TRASH- I wish the economy would have killed it completely. I don't see how anyone can call anything in that racing class an achievement. Probably why when NHRA is televised, they leave it out and show everything else.

JUNK- no factory benefits from it- except maybe Harley, when redkneck retards buy a VRod becuase they think they saw one go down the track victorious.

Buell? Another name for "shit"
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1badzx12r


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posted March 09, 2012 08:19 PM        
quote:
no this is not the Harley class NHRA about five or six years ago handed the Harley guys, the rulebook
Ken




how can you argue debate it not the harley class .. them suzuki's are just there because they too dumb to leave
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SteddyTeddy


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posted March 10, 2012 08:21 AM        
If they would let the inline 4 guys build fully custom 1 off, CNC machined motors like the V-twins get to do, it would be a whole new race.
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RICH CRAFT 1


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posted March 10, 2012 11:22 AM        
I don't think they're gonna give the in-line4 guys anything! in today's qualifying the V-twin guys or,

1. Eddie Krawiec Screamin' Eagle/Vance & Hines 6.750 198.03
2. Hector Arana Jr Lucas Oil Buell 6.812 193.63
3. Hector Arana Lucas Oil Buell 6.842 193.99
4. Andrew Hines Screamin' Eagle/Vance & Hines 6.843 195.14
5. LE Tonglet Nitro Fish Suzuki 6.894 192.93
6. Karen Stoffer GEICO Powersports Suzuki 6.894 192.58

with those kind of numbers. How long do you think it will be before Karen Stoffer on the GEICO motorcycle loses her sponsorship? what company will pay their people. The money it takes to run one of these bikes, to drive 2000 miles, to get run over like that.

Ken
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1badzx12r


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posted March 10, 2012 11:40 AM        Edited By: 1badzx12r on 10 Mar 2012 18:43
quote:
If they would let the inline 4 guys build fully custom 1 off, CNC machined motors like the V-twins get to do, it would be a whole new race.



yada yada yada ..



gs are lighter
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Mach3


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posted March 10, 2012 12:15 PM        
TRUE, NHRA PRO STOCK MOTORCYCLE CLASS IS SO BIAS IN FAVOR OF HARLEY, THAT IT IS JUST A SPRINKLE HERE AND THERE OF THE OTHER BRANDS TO SAY THEY ACCOMPLISHING
SOMETHING. I SAY IF YOUR DESIGN IS INFERIOR, FIX IT AND RUN THE SAME DISPLACEMENT AS THE REST.

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mathews


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posted March 10, 2012 02:07 PM        
Its funny to me to hear guys complain how unfair heads up racing is.The same guys that hate bracket racing.All heads up racing leads to is the guy with the most money eventually wins
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kaw now


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posted March 10, 2012 02:13 PM        
Show me a harley with an induction set up like this twin down draft carbs, head looks cut out of a small block chevy or something. Total BS and the announcers act like its a even race against the high revving jap bikes.




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CajunBoyz


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posted March 10, 2012 02:27 PM        
At least Suzuki has parts that are modified from the factory parts. I remember when a magazine did an article when Bryon Hines "made " the fiirst pro stock ones. Quote Bryon said the only thing on this bike that is Harley is the name..
Give Jap bikes the same respect & do the same things , level the dam playing field.
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kaw now


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posted March 10, 2012 02:39 PM        
really if the issue was push rods as to why they use an extra 983cc's even the cubes and use the v-rod design which has overhead cams. They don't want to use overhead cams and give up the unfair size advantage cause it's an american bike with big following. Look that harley is faster than them jap bikes.
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Audioboyz


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posted March 10, 2012 02:56 PM        
But what bikes do most street bike dudes buy that want to go fast?I know which one it isn't.
It was the same with NASCAR and NHRA in the seventies.Chevy couldn't win by the rules so they made their own for the junk bowties.Put small carbs on the Hemis in NASCAR and added weight per cubic inch in Pro Stock on the Hemis.Today NASCAR is a joke so is NHRA with their 1000 ft track for the fuel clases.
Craig
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1badzx12r


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posted March 10, 2012 03:28 PM        Edited By: 1badzx12r on 10 Mar 2012 22:33
quote:









I WANT 1


IF ITS SO DAYUM UNFAIR ..WHY DON'T THE JAPS USE THEIR OWN TWIN CYLINDER ENGINES ..
They copied harley design once for m109 and vulcan and other twin cylinders... BUT ITS EASIER TO CRY AND WHINE
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kaw now


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posted March 10, 2012 03:58 PM        
Bike companies don't make pro stock bikes so Japan won't make a twin for pro stock. You need that S&S motor just cough up the dough.
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kawa74


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Posts: 226
posted March 10, 2012 03:59 PM        
quote:
quote:









I WANT 1


IF ITS SO DAYUM UNFAIR ..WHY DON'T THE JAPS USE THEIR OWN TWIN CYLINDER ENGINES ..
They copied harley design once for m109 and vulcan and other twin cylinders... BUT ITS EASIER TO CRY AND WHINE


$30,000 + each, 370+ hp , and per NHRA rules you must have a Spare to race
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1badzx12r


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posted March 10, 2012 04:14 PM        
MAN i don't even go to NHRA tracks .. i just want the motor to stick in a busa ..wouldn't that be the shittz
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supra5677


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posted March 10, 2012 04:39 PM        
Iv'e also been pissed off about this for years. But consider. If they evned the rules, Harley would have a hard time selling bikes..
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eklipse636


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posted March 10, 2012 05:27 PM        
But are bikes sold because of pro stock bike races? I Doubt it
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JZX


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posted March 10, 2012 08:08 PM        
quote:
quote:









I WANT 1


IF ITS SO DAYUM UNFAIR ..WHY DON'T THE JAPS USE THEIR OWN TWIN CYLINDER ENGINES ..
They copied harley design once for m109 and vulcan and other twin cylinders... BUT ITS EASIER TO CRY AND WHINE


C' mon squatch, you know that nothing in that motor's design or material is HD at all, yet they paint Harley all over the machine.

Also, what intelligent engineer on the planet would "copy" any part of Harley Davidson, except maybe their shirts or jackets....

Let's go ahead and copy something that rattles itself apart and make 65 hp..
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1badzx12r


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posted March 10, 2012 08:18 PM        Edited By: 1badzx12r on 11 Mar 2012 03:19
Dark Ages

In the beginning, there was the single-cylinder motorcycle engine, and it was good. Early motorcycles, like all vehicles in the late 19th century, were crude—essentially bicycles with unreliable, oil-dripping, flame-belching internal-combustion powerplants often scarcely stronger than a man. In other words, they were a perfect match for America's highway system, which wasn't much of a system at all. But everything improves, and eventually the need for more power (certainly more reliability) than a single-cylinder engine could provide won out on the desire for utmost mechanical simplicity. After all, a single is about as simple as it gets, but running it hard may result in a less reliable engine than a more complex design that's loafing along. If you're already making one cylinder, it's not too much of a stretch to imagine plonking another on a single crankshaft—bingo, double the displacement and, so the theory goes, double the power.


In fact, done right there are some great advantages to the V-twin; for instance, one cam can actuate valves in two different cylinders or a single carb could share two intake manifolds. Strictly speaking, you wouldn't necessarily be doubling the parts count for a useful boost in (still, at this point, theoretical) power.

Indian built the first V-twin in 1903, the same year as the first Harley-Davidson (a single), but the layout appeared to have so many intrinsic benefits that it quickly spread. Harley's first V-twin, which debuted in '09, was not a success—providing a fantastic engineering lesson that simply doubling the cylinders was not enough. Harley didn't offer the V-twin in '10, but rebounded with the Model 7D in '11 that clearly formed the nucleus of what Harley was to become. Say what you want about Harley-Davidson, but the lads learned from their mistakes in the early days.

From these humble beginnings—really just an engineering expedient to getting more power by using two cylinders on a common crankcase—the V-twin engine propelled Harley-Davidson and Indian into a prominence bowed but unbroken by the Great Depression. That Harley survives today has to do with luck and business acumen as much as engineering talent—many would argue that Indian was technologically more advanced, and that motorcycles from all parts of the globe could do anything a Harley could do, only better and for less cash.

Harley's fortunes ebbed and flowed throughout the 20th century, and we rejoin the plot as Japanese manufacturers, circa the late '70s, notice that the "classic" Harley-Davidson—basically a touring bike still powered by what at the time was a terribly outdated and woefully unreliable air-cooled V-twin engine—was moving well enough from showrooms to warrant a closer look. (More than that, Harley had survived the "bad boy" image of the '60s and, as a manufacturer somewhat less than a cultural icon, was on the verge of cashing in on the outlaw profile.)

Fresh Wind From the East


Soon, Japanese customs arrived, blatantly but often inexpertly styled along Harley lines—meaning a "teardrop" tank, a stepped saddle, chrome fenders, silly buck-horn handlebars and even a vestigial sissy bar. Yet there was a critical distinction: Japan Inc. didn't make a suitable, big-inch V-twin—and anyway, it was considered unseemly to so boldly go where Harley had been before—so these cruiser caricatures were powered by whatever was around—big, air-cooled four-cylinder engines, vertical twins, thumpers, what have you. At the height of the insanity—the late '70s and early '80s—Japanese manufacturers tried everything, including an across-the-frame, liquid-cooled, pushrod, four-valve V-twin. (Honda, we all thought at the time, would design something just to prove it could, not because it was the best configuration for the job.)

And yet all the newcomers were missing a critical ingredient—the V-twin engine configuration that Harley had defined and that in turn absolutely defined Harley, and by extension any concept of an "American" motorcycle. Yamaha broke into the category with the Virago 750 in '81, offering a handsome and capable motorcycle that was more like a Harley (OK, a small, forward-thinking Harley) than any of the Japanese bikes before, and it was an instant success. Thus emboldened, the Asian manufacturers wasted no time bringing V-twin engines to the blossoming "custom" market. By '83, Honda had two Shadows (a 500 and a 750), plus the hairy V4 V65 Magna (and a smaller version whose descendent is still made), and Yamaha had a bigger, 920cc Virago. Two years later, the Kawasaki Vulcan 750 debuted. We'll ignore Suzuki's ungainly Maduras of '85 and instead trumpet the arrival of the Intruder in '86. Thus, by the mid-'80s, each of the Big Four had at least one V-twin cruiser, and such nonendemic brands as Ducati and Moto Guzzi were trying their hands at American-styled bikes.

Today, metric cruisers are sales darlings, and every one that sells worth a damn has a V-twin engine. Why do you suppose that is?

Well, Duh—They're Like Harleys

It's impossible to detach the Harley experience from the V-twin experience, isn't it? Virtually every mention of what it's like to ride Big American Iron includes some reference to the familiar potato-potato sound, to the thumping of two big pistons as the heartbeat of the beast. This strain of character comes from many things, not just the fact that the motorcycle is motivated by a loping, low-revving V-twin; it's the heft of the controls, the sturdy clank of the transmission moving from gear to gear. It comes from the Harley's ability to glide away from a stop with little throttle and the feeling of bottomless torque. Such sensations can be had from other engine configurations—a modern, 955cc Triumph Speed Triple has that utterly at-ease feeling, and no one would dare say a bike like Suzuki's Hayabusa is a slug off the line. But they're different, very different.

Fury, But Sound, Too

When Harley took steps to trademark the sound of its engines, it embraced a way to protect against others using single-crankpin, 45-degree V-twins. And yet there's much more to an engine's exhaust note, or signature, than the spread between the cylinders, and, indeed, all current cruiser engines evoke the same emotional response from their loping cadences. (In yet another example of defining the breed, Harley's potato-potato note has come to symbolize freedom only because the idea is associated with the brand that makes that particular noise.)


V-twins make lots of distinctive sounds, and perhaps at the core of our appreciation for them is the idea that we can actually hear the combustion process in slow motion. Bang, bang...pause...bang, bang. It's a more natural-seeming rhythm than the regular, symmetrical buzz of a four-cylinder, and closer to a heartbeat than the chainsaw razz of an inline-four. Harleys sound the way they do because of the narrow V angle, which places the firing of the cylinders close together with a long pause. Again, think of: boom, boom...pause... boom, boom...pause.

As you'll see later, not all cruiser engines are built the way Harleys are, so their exhaust notes are different, too. But design orthodoxy has largely taken over, so current cruisers sound more similar than unalike, with a pleasing rumble that speaks of raw torque and untrammeled roads.

Good (and Bad) Vibrations


Unquestionably, what most riders perceive as the soul of the V-twin emanates from shudders and quakes from the engine room. Why do V-twins sound and feel as they do?

It's simple, actually. Modern V-twin engines are big mommas. If Honda's VTX 1300 is considered entry level, and Kawasaki made big hay about its Vulcan line getting a 1600cc iteration, you know you're talking about some seriously big bits and pieces. Inside your cruiser's engine are not the jewel-like pistons, anorexic connecting rods and nonexistent flywheels you'd find on a 600cc sportbike; no sir, these are big pistons moving a neighborhood away along a lengthy stroke. (Are we clear on this? Bore is the width or diameter of the piston inside each cylinder. Stroke is how far up and down that cylinder the piston travels.)

In fact, engine vibration comes from two principal sources: the inherent imbalances in the reciprocating parts (meaning they go back and forth or up and down inside the engine) and pulses descending from the combustion event itself—the ignition of fuel and air in the cylinder head. In other words, there's a kind of shake or vibration that is part of that engine's very design, present regardless of the power produced, and yet another that's the result of laying down the torque—much of this is the throb you feel as the bike launches away from the stoplight.

Inherent vibration is often associated with the V-twin mystique, but it's an unfortunate side effect of the most popular designs. Harley placed its two cylinders 45 degrees apart on a common crankcase mainly so the engine would fit into a bicycle-style frame originally intended for a single-cylinder powerplant. Unfortunately, a 45-degree Vee angle has a prominent vibration "signature."


Consider what's happening inside. Imagine you have a single-cylinder engine. The piston starts at the top of the cylinder (a place called Top Dead Center, or TDC) and travels downward; it moves slowly at first and travels the fastest midstroke. It has to stop suddenly and reverse direction at the bottom of the stroke, called Bottom Dead Center (BDC). This very motion creates a force; the piston wants to keep going, so the crankshaft it's connected to (and the crankcase that the shaft is rotating in) must absorb this acceleration. Typically, engine-makers add weight to the crankshaft. Called counterweights, they attempt to cancel out some of these imbalances. But this only goes so far. Vibration caused by the piston moving up and down is known as a primary force or imbalance because it occurs at the same frequency as crank rotation. There are other imbalances created in the engine we'll touch on later, but the primary imbalance is the one you notice most.

Adding a second cylinder to a single and creating a 45-degree angle between the two builds an engine with, it must be said, undesirable vibration characteristics. Although the primary imbalance is not as great as in a single, it's still very strong—this is why traditional Harley engines bolted solidly to their frames shake like a wet dog. One thing the H-D configuration has going for it is that vibration is isolated to the vertical plane because the parts of the connecting rods attached to the crank straddle one another and are not placed side-by-side. This is why Harley cylinders are directly in line, and other engines' cylinders are offset side to side. The Harley's big primary imbalance makes it relatively easy to counter by rubber mounting—you can locate the engine firmly left to right and allow it to shake its little heart out up and down—or in the case of the new Twin Cam 88B engines, by use of an internal counterbalancer (more on that later, too). The Harley engine also has a bit of what's known as secondary vibration—imbalances that occur at twice the engine speed—acting in the same plane as the primary imbalance. Think of the primary as the throb and the secondary as the sizzle.

Smoothing the Savage Beast

Historically, Harley has tried to manage the primary imbalance by fitting massive flywheels, which have the knock—an effect of smoothing power delivery—at the cost of making the engines "lazy" or unwilling to accelerate quickly, plus the penalty of the added weight of the assembly.

If primary imbalance is a bad thing, and the 45-degree V-twin has lots of it, is there a good V-twin configuration? You bet: The 90-degree Vee, like Ducati and Moto Guzzi use, has inherently counteracting primary forces and minor secondary imbalances acting in a plane perpendicular to the centerline of the Vee as viewed from the side. In other words, this design is naturally quite smooth for a twin-cylinder engine. (You want really smooth? Try an inline-six or a V12.)


If it's so good, why doesn't everyone use a 90? Well, it's difficult to fit into a frame gracefully and, let's face it, just doesn't look the cruiser part. Because even the most advanced metric cruisers embrace a profile made of the necessity of housing a 45-degree V-twin, the narrow Vee angle is considered the only way to go. Ah, yes, but how do you make it smooth?

Two methods prevail. One is to split the crankshaft where the connecting rods meet it, in effect offsetting the pistons to make the engine act more like a 90-degree Vee. Honda's Shadows, for example, set the cylinders 52 degrees apart and use offset crankpins. This makes the pistons rise and fall in their respective cylinders nearly 90 degrees apart. There's still a bit of imbalance leftover, entirely manageable by simple rubber mounts or leaving them unvarnished for the rider to enjoy.

The other method employs counterbalancers. Resembling tiny crankshafts without the rods, counterbalancers are merely weights rotating on a shaft timed to exert a force opposite to the inherent, undesirable vibration of the engine. Counterbalancers have the minor disadvantages of adding weight to the engine and sapping a bit of horsepower, but otherwise they're technology superbly well suited to making a shaker into a smoothie.


So you've got your paint-mixing, bar-shimmying engine that can't help it because of the movement of the internal parts, and then you've got the kind of vibration we all like—that stammering, rubber-hammer jab you notice on acceleration. This is a result of the combustion of fuel and air in the cylinder setting all those carefully chosen balance characteristics, well...out of balance. (After all, there's no corresponding bump when the piston reaches Bottom Dead Center.) What's more, some of the vibration you feel—the very heartbeat of the machine—is the result of torsional stresses in the engine. Every time a cylinder lights off, the crankshaft, which seems massively strong sitting on your desk (doesn't everyone have a stroker Harley crank on his desk?), actually twists a bit under the load. Then, almost as quickly, it springs back. Because four-cylinder engines have twice as many combustion events, you'll never feel this thumpa-thumpa from a multi. (And yes, by that we mean more than two.)

Honda has leveraged the power-pulse vibration to the max with the VTX 1800. There are myriad vibration dampers in the driveline to help take the worst shocks out of those massive pistons rising and falling, but the system is cleverly designed to remove the harshest jabs while accentuating the vibration that riders perceive as desirable. More technology for the good of motorcycling-kind.

It's About The Power, Baby

Our love of the V-twin engine extends beyond its distinctive texture because it's a wonderful real-world powerplant. Let's step back once more to theory—don't worry, we'll be quick about it—to remember that an internal-combustion engine is little more than an air pump. Consume more air—and put correspondingly more fuel into it—and you get more power. There are several ways to improve power: As suggested, allow the engine to take in more air (and, just as importantly, expel more air) and you'll produce more work. At the same time, if you increase engine speed, it can do a given amount of work over a shorter period of time, which gives you more horsepower. Finally, you can take that fuel/air mixture and squeeze it harder, making the combustion event—it's not an explosion but a very rapid, controlled burn of the mixture—more powerful. By "squeeze" we mean to increase the compression ratio—which is the difference in cylinder volume between TDC and BDC. The higher the compression ratio, the greater the BANG...up to a point. It turns out that for the ideal cruiser engine, bigger is often better, and once the decision is made to hit a certain displacement target, the remaining choices come prepackaged, like mechanical Lunchables.

Historically, V-twin engines have been undersquare—or long-stroke—engines; their bores measured less than the length of the stroke. (Square is when the bore and stroke are equal; oversquare means the bore is bigger than the stroke is long.) A long-stroke engine is inherently good at making low-end torque, and, as though to give something back, inherently limited in the ways it might exploit anything but low-rpm power. For starters, a long-stroke engine, for any given rpm, makes its pistons move along the bore faster and sustain harsher starts and stops at the extremes of piston stroke. (In fact, the dynamic loads on the bottom end go up with the square of the engine speed.)

Though bigger is normally supposed to be stronger, the 1130cc Harley-Davidson V-Rod engine makes enough power to beat all other OE V-twins.

For a given overall displacement, a long-stroke engine will have a smaller bore, which makes less room for the valves. The smaller the valves, the less air the engine can pump. But there's a countering effect. A long-stroke engine with smallish valves may turn asthmatic at elevated revs, but it breathes very well and very efficiently at low speeds. Conversely, engines designed for high-rpm power often have large valves, camshaft timing that opens those valves wide and zippo for low-end responsiveness; until the engine is really spinning, those big valves and tall cam lobes are dancing the wrong steps.

In theory, a low-revving engine doesn't need more than the minimum number of valves—one each for the intake and exhaust. Yet the majority of Japanese engines feature a three- or four-valve design. In large part this is because that's what the engineers are familiar with, but it's also true that a good four-valve head can be more efficient than a two-valver even at low revs. It's all in the design.

Harley is once more the archetype. The engines are large—though bikes such as the VTX and the Vulcan 2000 have raised the bar on max cubes—with small valves, modest compression ratios and an overall design that makes the best use of the low-speed bias. Who needs overhead cams when the max engine speed is less than 6000 rpm? (Apparently not Harley...or Moto Guzzi or Yamaha.) Who needs massive valves when the piston speeds similarly keep a lid on rpm? Honda's taunt that the VTX has an exhaust valve the same size as a P-51 Mustang V12 Merlin fails to point out that the airplane has two such in each cylinder while the VTX has but one.

It would be both uncouth and inaccurate to say Japanese cruiser-makers simply took the Harley concept and modernized it. Once the industry cottoned to the idea that customers wanted V-twins (and, basically, V-twins only), they sat down and did the best they could. True, early versions could be awkward-looking, but engineers eventually figured out that American riders want visual simplicity and a ton of low-end grunt. Through evolution, trial and error, sales successes and failures, manufacturers have found themselves with handsome, genuinely powerful engines that somehow manage to combine charisma and civility, answering the question of whether the V-twin is an ideal cruiser powerplant with a pugnacious, "Just how big would you like it, Jack?"


http://www.westcoastbikers.com/v-twin-design-engineering
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http://www.youtube.com/watch?v=S06nIz4scvI

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