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Erico

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Hello to you all, I'm brand new to this forum but not new to the Mighty Vmax. I've had several over the past 30 years and have a strange affliction. I actually understand the things and enjoy restoring them and generally working on them. Only do my own and friends. My current Vmax is a 1998 full power with 140.6 bhp at the back wheel. Measured on TurboPacs dyno in Durham City UK. K&N air filter, 4 into 1 Stainless exhaust and larger main jets. That's all it takes to unleash some serious power. Regards Erico.:rocket bike:
 
.... er.... Dyno.

Welcome to the forum. Excellent results from mods by a lot of us with significantly less results.
 
Those are Imperial Horsepower, which as everyone knows, are 1.270270270... of an SAE horsepower. (just poking a bit of fun here, don't take this seriously)

Let's see some pics, we all love pics.

Have you run it at the strip? I think you should be able to get deep into the 10's w/that horsepower.
 
Last edited:
Erico said:
Hello to you all, I'm brand new to this forum but not new to the Mighty Vmax. I've had several over the past 30 years and have a strange affliction. I actually understand the things and enjoy restoring them and generally working on them. Only do my own and friends. My current Vmax is a 1998 full power with 140.6 bhp at the back wheel. Measured on TurboPacs dyno in Durham City UK. K&N air filter, 4 into 1 Stainless exhaust and larger main jets. That's all it takes to unleash some serious power. Regards Erico.:rocket bike:
Click to expand...
What's a stock Vmax put out on the same dyno? Or, any stock bike?
 
Unfortunately, I don't believe higher octane will make you run faster in a normally-aspirated bike, it just has to be sufficient to prevent detonation or preignition.

Our bike isn't designed for premium octane. The factory spec is for "regular" in the USA. What does that label say under the seat?
 
Dragmaxster said:
The uk minimum octane is 95,97,99 and 102.
That's why it is $7.31 a gallon for (95 octane).
That's something in the water.:confused2:
Click to expand...

Available at the pump is 95 RON and 98 RON. Normal unleaded currently at $6.27 for a US gallon

Your right about the water or perhaps it is the air if that's what Mr Erico's r.w.h.p. is. My 1300/ flat slides/ ported head motor has some serious problems as it only gave 140 when dynoed several years ago!
Curses, more sleepless nights wondering how to round up the lost GG's.....
 
Everyone is correct. The factors we are all used to in the U.S. are not easily compared to other places. Dyno measurement numbers vary in both type and function. Typically SAE smoothing 5 is what you'll see used here which is not what i've seen on some readouts from other countries.

The fuel is also measured differently. Our 91 is comparative to their 95. Here's some more info on the subject: https://en.wikipedia.org/wiki/Octane_rating
 
Here's some more info, discussing octane. Check the last sentence:

http://www.economist.com/blogs/babbage/2012/09/octane-ratings

EVEN at the cheapest petrol station in your correspondent's neighborhood, filling up the family kidmobile with premium (91 octane) fuel now costs over $70. As the meter clocks up dizzying dollar amounts, he looks longingly at the regular (87 octane) pump. Switching from his vehicle’s recommended premium-grade fuel to the cheaper variety would lower his fuel bill by at least 20 cents a gallon (more than five cents a litre). The question is, would it be worth it?

On the surface, the decision appears easy. Because the name “premium” implies a souped-up fuel that packs an extra punch, many motorists actually believe it delivers more oomph or miles per gallon—and may therefore represent good value. The truth, however, is that premium contains no more energy than regular petrol—around 114,000 British Thermal Units per gallon, depending on the season, the region, the local pollution requirements, and the amount of bio-ethanol that has to be added to petrol in America by law to keep the country’s corn-growers in clover (see “Competition at the pump”, August 20th 2012). The difference between premium and regular petrol lies in the blend of hydrocarbons used to make the fuel, and the package of additives mixed into it.

Nowadays, petrol is made up of hydrocarbons (mainly paraffins, naphthenes and olefins) produced in a catalytic cracker or reformer. The refinery process breaks the crude oil’s large hydrocarbon molecules into smaller ones by vaporising them in the presence of a powdered catalyst (an absorbent mineral such as zeolite). The blend varies depending on where the crude came from, the refinery equipment used, and the grade of petrol being produced.

Additives are included to reduce carbon build-up inside the engine, improve combustion, inhibit corrosion and allow easier starting in cold climates. Fuels that meet the requirements for “Top Tier Detergent Gasolines” (a voluntary standard endorsed by BMW, General Motors, Honda, Toyota and Volkswagen) contain more detergent in their additive packages than the minimum required by the authorities.

Another key additive that blenders stir into their brew is ethanol. That is done these days primarily to boost the fuel’s octane rating. A higher octane rating allows an engine to use a compression ratio of, say, 12-to-one instead of a more usual ten-to-one. The greater the compression, the higher the temperature within the combustion chamber. And the higher the temperature, the greater the thermal efficiency and power produced. In a nutshell, high-compression engines designed for performance need high-octane petrol.

Though ethanol has less energy per gallon than petrol, it has a considerably higher research octane number (RON)—around 108 to premium’s 97. It should be noted that this is not the octane rating seen on the pump in America. The RON figure results from a laboratory test done using a special engine with a variable compression ratio.

In the fuel test, the compression is raised until the engine begins to “knock”—ie, the fuel in the cylinder ceases to burn smoothly and instead detonates before it can be ignited by the spark plug. The cylinder pressure at which this occurs is then compared with that achieved while the engine is running on a reference fuel (a mixture of iso-octane and n-heptane). The ratio of the two pressures provides the RON of the fuel in question.

A better way of measuring a fuel’s ability to resist knocking under load is the so-called motor octane number (MON) test. This uses a similar test engine, but with a preheated fuel mixture, a higher engine speed and variable ignition timing. Because it uses more real-world conditions, the MON rating is typically eight to ten points lower than the equivalent RON figure.

In Europe, the octane rating on the pump is simply the RON figure. America, by contrast, uses the average of the RON and the MON figures, called the AKI (anti-knock index). Thus, 97 octane “super unleaded” in Britain is roughly equivalent to 91 octane premium in the United States.

Whatever the test, the point is that knocking needs to be avoided at all cost. If allowed to continue, it can quickly cause an engine to disintegrate. That is because when the air-fuel mixture in the cylinder detonates spontaneously before reaching the top of its compression stroke, the rising piston confronts a wall of rapidly expanding gases from the explosion, which attempt to force the piston back down the cylinder. The stresses caused by suddenly trying to reverse the rotation of the engine can become high enough to shatter the pistons, connecting rods and parts of the crankshaft.

To prevent that happening, a high-compression engine uses a blend of hydrocarbons that is somewhat less combustible than normal. Ethanol has an auto-ignition temperature of 362ºC, while petrol bursts into flames without a spark between 246ºC and 280ºC, depending on the blend. Therefore, adding a little ethanol to petrol can raise the auto-ignition temperature enough to prevent the blend from igniting purely from the heat generated during compression.

On the face of it, then, a motorist would seem ill-advised to use regular petrol in a car with a high-compression engine. That was certainly the case in the past. But cars today have sensors that listen carefully for the knocking sound, and instantly retard the ignition system when they detect that detonation is about to happen.

The delay in delivering the retarded spark allows the piston to start moving downward on its expansion stroke before the ignition actually occurs. That provides additional room in the cylinder head for the gases to expand and thereby reduce their damaging peak pressure—and so burn in a more controlled manner.

To sum up, if the car’s handbook says that premium petrol is “recommended” (rather than insisting it is “required”), then the engine will automatically adjust itself to run smoothly on a lower octane fuel. Because of the retarded ignition, the engine will, of course, produce less power, and have slightly higher fuel consumption. But the poorer fuel economy is likely to be outweighed by the savings at the pump.

Even so, your correspondent remains reluctant to make the switch. One reason is that no one has been able to tell him what damage is done, if any, by running the engine permanently in a retarded state, and forcing the anti-knock system to remain active all the time.

Another reason is because all the vehicle’s emissions testing was done using the recommended grade of fuel. Despite the fact that modern fuel-injection systems adjust the air-fuel mixture for changing conditions, your correspondent still has no idea how much more pollution the car might dump into the atmosphere if he switched to regular. Premium certainly has a better additive package, which helps keep the tailpipe clean as well as the inside of the engine.

But his biggest reason for sticking with premium, though, is that he was well aware that the car needed 91 octane to work properly when he bought it. And having paid upfront for the higher performance, he is reluctant now to throw that benefit away.

As for those who earnestly believe (and quite a few do) that filling the family Toyota with premium will somehow make it go faster or deliver more miles to the gallon, all one can say is don’t bother. As one wit noted, the only thing it will make run faster is money from your pocket.

And an article from Edmund's about horsepower ratings:

If you've spent any time around cars or car people you're familiar with the term horsepower. And while you may have a general idea of what horsepower refers to, its exact definition and how that definition plays out in the real world can be a bit confusing. Specifically, the terms "net horsepower" and "wheel driven horsepower" are commonly seen in magazine road tests or vehicle spec boxes. But what exactly do they mean and what, if any, difference is there between the two?
We'll get its basic definition out of the way first and then move on to the difference between net horsepower and wheel-driven horsepower.
Horsepower is officially defined as "the amount of energy required to lift 550 pounds, one foot, in one second." This definition dates back to when cars didn't even exist and, despite the worldwide acceptance of the metric system (America not withstanding) in which feet have been replaced by meters, the definition remains in use today.
Generally speaking, horsepower is an indication of how capable a vehicle is at moving itself around and, consequently, the more horsepower a vehicle possesses, the quicker it can move between two points. In addition to determining how quickly a car or truck can move, horsepower has a direct relationship to top speed. As a vehicle's speed rises, additional horsepower must be expended to push it through the atmosphere. Of course, aerodynamics play a major role in top speed as well and most of today's performance cars owe as much to aerodynamics as they do to horsepower for their ability to go 150+ mph.
So if the definition of horsepower is so straightforward (550 pounds moved one foot in one second), how can the same vehicle have different horsepower ratings? For instance, Chevrolet rated the 1998 Corvette's 5.7-liter V8 at 345 horsepower. Yet test in HOT ROD magazine found the car to have 285 horsepower. So what gives?
The disparity between these two figures comes from the fact that one is a gross horsepower rating and the other is a wheel-driven horsepower rating. Gross horsepower is a measurement of engine output, taken at the flywheel, without the engine installed in a vehicle. Since the engine has no load on it, all of its energy can be used for making horsepower.
Wheel-driven horsepower, by comparison, is a measurement taken at the driven wheels of a vehicle on what's called a dynamometer. This is done by placing the vehicle's driven wheels on a large roller and accelerating the wheels up to redline in first or second gear. The vehicle's ability to turn this roller is measured and calculated to come up with a figure that represents how much horsepower is actually available to move the vehicle around -- or real-world horsepower. Because a frictional loss between the engine and the driven wheels is unavoidable, wheel-driven horsepower will always be less than gross horsepower.
How much less wheel-driven horsepower will depend on how many mechanical parts exist between a vehicle's engine and its driven wheels. Since we already mentioned a late-model Corvette, we'll use it as our example. The 345 horsepower that initiate in the Corvette's engine compartment have to travel through a transmission, driveshaft, rear-differential, and two axle shafts (one for each rear wheel). That's four separate mechanical components taking a bite out of the `Vette's horsepower before the rear wheels even begin to turn. Suddenly, the 285 wheel-driven horsepower rating doesn't seem so hard to believe.
On front-wheel drive cars with transverse-mounted engines, the frictional loss is often less severe because horsepower only has to travel from the engine, through the transmission and down two short driveshafts before reaching the wheels. It should be noted, however, that in the same HOT ROD article, a front-wheel drive Dodge Neon R/T, rated at 150 net horsepower, could only muster 117.1 wheel-driven horsepower when placed on a dynamometer.
Obviously, another factor to consider in this discussion is how accurately the manufacturers rate their own engines. It's hard to believe that the Corvette and Neon could lose 17 and 22 percent of their engine's horsepower in just frictional losses. Most experts agree that a 10 to 15 percent loss is normal. This does not necessarily mean that the manufacturers are lying. The additional drop could come from a number of causes including variations in engine performance and dynamometer readings. It could also be that the manufacturers are dealing with an expertly tuned engine's running under controlled conditions in a laboratory rather than a mass-produced engine that was put together on an assembly line and sold at a dealer's lot.
Whatever the cause, it's important to remember that there will be a loss of horsepower between the engine and the rear wheels. If you really want to know how powerful a vehicle is, test drive it. If you're looking for an accurate horsepower figure, a dynamometer run is the only way to know for sure.

http://www.edmunds.com/car-technology/horsepower-gross-vs-real-world.html
 
A recent conversation from the U.K., on the "telly"........

"Hello Max, this is Erico"
"G'day, mate. What's up with me old friend?"
" Max, I was thinkin' of joinin' that forum across the pond. How would a bloke make a good first impression?"
"Easy, Erico. Them Yanks and Canucks go bonkers over horsepower and dyno results. Tell them your bike has 140 horsepower at the rear tyre"
"BLIMY, jolly good idea, Max! I'll do just that!"
"And if you REALLY want to impress the bloody wankers, tell 'em you get better mileage and horsepower on premium petrol!"
"BLOODY 'ELL! I'll start the post right now. Thanks, mate! Cheerio!"
 
Miles Long said:
A recent conversation from the U.K., on the "telly"........

"Hello Max, this is Erico"
"G'day, mate. What's up with me old friend?"
" Max, I was thinkin' of joinin' that forum across the pond. How would a bloke make a good first impression?"
"Easy, Erico. Them Yanks and Canucks go bonkers over horsepower and dyno results. Tell them your bike has 140 horsepower at the rear tyre"
"BLIMY, jolly good idea, Max! I'll do just that!"
"And if you REALLY want to impress the bloody wankers, tell 'em you get better mileage and horsepower on premium petrol!"
"BLOODY 'ELL! I'll start the post right now. Thanks, mate! Cheerio!"
Click to expand...

:rofl_200::rofl_200:
That pretty damn funny Miles.
 
Miles Long said:
A recent conversation from the U.K., on the "telly"........

"Hello Max, this is Erico"
"G'day, mate. What's up with me old friend?"
" Max, I was thinkin' of joinin' that forum across the pond. How would a bloke make a good first impression?"
"Easy, Erico. Them Yanks and Canucks go bonkers over horsepower and dyno results. Tell them your bike has 140 horsepower at the rear tyre"
"BLIMY, jolly good idea, Max! I'll do just that!"
"And if you REALLY want to impress the bloody wankers, tell 'em you get better mileage and horsepower on premium petrol!"
"BLOODY 'ELL! I'll start the post right now. Thanks, mate! Cheerio!"
Click to expand...

[email protected] said:
:rofl_200::rofl_200:
That pretty damn funny Miles.
Click to expand...
+1 Mike, he ain't just another pretty face!:th_peace:
 
Miles Long said:
A recent conversation from the U.K., on the "telly"........

"Hello Max, this is Erico"
"G'day, mate. What's up with me old friend?"
" Max, I was thinkin' of joinin' that forum across the pond. How would a bloke make a good first impression?"
"Easy, Erico. Them Yanks and Canucks go bonkers over horsepower and dyno results. Tell them your bike has 140 horsepower at the rear tyre"
"BLIMY, jolly good idea, Max! I'll do just that!"
"And if you REALLY want to impress the bloody wankers, tell 'em you get better mileage and horsepower on premium petrol!"
"BLOODY 'ELL! I'll start the post right now. Thanks, mate! Cheerio!"
Click to expand...

Oh ha ha.....now perhaps you would be good enough to tell me where you have hidden your snooping device!

PS: There must have been some interference on the tape, it wouldn't have been 'G'day, mate' (a term frequently used by our Antipodean brethren, or as we prefer to call them, convicts). Under the static what you would probably have heard is 'What ho, ol' chap'.
 
MaxMidnight said:
Oh ha ha.....now perhaps you would be good enough to tell me where you have hidden your snooping device!

PS: There must have been some interference on the tape, it wouldn't have been 'G'day, mate' (a term frequently used by our Antipodean brethren, or as we prefer to call them, convicts). Under the static what you would probably have heard is 'What ho, ol' chap'.
Click to expand...
My girlfriend from Nottingham shire says that they are the hillbilly version of the British. Lol...not like that is a bad thing...lol

Sent from my SCH-R890 using Tapatalk
 
MaxMidnight said:
Oh ha ha.....now perhaps you would be good enough to tell me where you have hidden your snooping device!

PS: There must have been some interference on the tape, it wouldn't have been 'G'day, mate' (a term frequently used by our Antipodean brethren, or as we prefer to call them, convicts). Under the static what you would probably have heard is 'What ho, ol' chap'.
Click to expand...

Ha! I just KNEW it was you that put him up to it, Max!:biglaugh:
Yup, got my vernacular a tad mixed up. Must've been the influence of all those Aussies and Kiwis on this forum.
I'll brush up on my Cockney, by spinning my numerous Long John Baldry :punk:albums.
 
A tall thespian of tunes, that LJB, Miles, I always laugh when I hear, "Don't Try to Lay No Boogie-Woogie on the King of Rock & Roll.":rofl_200:
 
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