Why do some brands only publish tq and not hp?

Messages
5,295
How come some manufacturers like Harley Davidson and Polaris (Victory, Indian) show only torque on the spec sheet but keep the horsepower value a secret? It makes calculating the power-to-weight ratio impossible. Other makers publish everything. For instance, Ducati shows my Multistrada 1200cc at 91.8 lb-ft and 150 hp, @ 454 lbs dry. Why hide it?
 
Messages
2,535
Location
Nowthen, MN
The American companies are probably afraid of getting sued when someone puts it on a dyno and it doesn't produce the advertised HP. It's already happened with lawn mower engines.
 
Messages
141
Location
PA
Of the brands you mention, I would say that it is because they are very large engines that produce impressive torque figures at low rpm, but because they are relatively low rpm engines, the horsepower figures are not impressive. I don't know if this applies to Polaris however.
 
Messages
26,136
Location
MA, Mittelfranken.de
In th world of torque numbers the big V Twin looks great but in the HP numbers appears to be under powered. 86 lb-ft doesn't sound bad but 122 HP doesn't sound great when compared to the Ducati smaller displacement V Twin. Advertising smoke and mirrors nothing more, customer starts looking at specs just throw some more mirrors at them an generate more smoke.
 
Messages
2,573
Location
Deep in the heart of Jersey
Well, if your buying a bike for racing, or "high performance", it probably matters to you how many ponies your getting. But, if your going to cruise the highway at a relaxed speed, knowing you have power to go up a steep hill or to pass a slow moving truck, having decent torque is probably all that matters to you.,,,
 
Messages
36,516
Location
ME
Originally Posted By: KD0AXS
The American companies are probably afraid of getting sued when someone puts it on a dyno and it doesn't produce the advertised HP. It's already happened with lawn mower engines.
The thing about lawn mower engines is their blade speed is limited by the CPSC and so their HP numbers were at a fictional, higher speed not obtainable in the real world. I wonder if there's something about stock pipes or tune that actually makes equal or better HP than loud pipes, and HD doesn't want the backlash. Or they want to market a bike as "tune it yourself and see what you get". Or some smog thing just kicked in and it's like the SAE/NET measuring in the early 70's that also coincided with smog rules.
 
Messages
14,505
Location
Top of Virginia
Originally Posted By: eljefino
Originally Posted By: KD0AXS
The American companies are probably afraid of getting sued when someone puts it on a dyno and it doesn't produce the advertised HP. It's already happened with lawn mower engines.
The thing about lawn mower engines is their blade speed is limited by the CPSC and so their HP numbers were at a fictional, higher speed not obtainable in the real world.
Yeah, it's not necessarily that they didn't produce the advertised horsepower, it's that the advertised horsepower is at a higher-than-allowed engine speed to keep the blade tip speed under 19,000 feet per second. So they found themselves in the uncomfortable position of advertising a lower power figure if they wanted to keep selling on horsepower. Torque is a larger number, so they went with that. As far as Harley, they probably don't make the horsepower that other brands make. They're not exactly high-revving engines. They're probably tuned for torque and they run well in that configuration. But you can't "bench race" with an engine tuned for torque.
 
Messages
1,154
Location
Richmond, VA
Similar cases; advertise what people are going to be comparing, usable power. I don't care how many Hp a lawnmower has I care how hard it's swinging that blade to make it through the tough stuff and not bog down.
 
Messages
524
Location
sc/fl
Because their HP numbers aren't impressive at all. Hp is very much RPM dependent, and when you're 1800 puts out significantly less HP than another brands 600. Well it just doesn't make for a favorable comparison, whether they're in the same category of bike or not.
 
Messages
5,653
Location
Central IA
Indeed, the big V twins do not make much HP for their size. They are simply low revving "grunt" motors and in the American sub conscience "Horsepower is king" so if you advertised the HP numbers I think many people would be disgusted with them. So they play up on their strengths, the torque numbers.
 

LoneRanger

Thread starter
Messages
5,295
The Harley's and Victory's have about 122 hp? That's not bad, they shouldn't hesitate to show that on the spec sheet.
Originally Posted By: Trav
In th world of torque numbers the big V Twin looks great but in the HP numbers appears to be under powered. 86 lb-ft doesn't sound bad but 122 HP doesn't sound great when compared to the Ducati smaller displacement V Twin. Advertising smoke and mirrors nothing more, customer starts looking at specs just throw some more mirrors at them an generate more smoke.
 
Messages
5,653
Location
Central IA
Originally Posted By: LoneRanger
The Harley's and Victory's have about 122 hp? That's not bad, they shouldn't hesitate to show that on the spec sheet.
Originally Posted By: Trav
In th world of torque numbers the big V Twin looks great but in the HP numbers appears to be under powered. 86 lb-ft doesn't sound bad but 122 HP doesn't sound great when compared to the Ducati smaller displacement V Twin. Advertising smoke and mirrors nothing more, customer starts looking at specs just throw some more mirrors at them an generate more smoke.
http://cruiser.mototribe.com/discuss/horsepower-and-torque-numbers More like the big Twin Cam has 95hp out of 1800cc's of engine. So that is a little less than a Yamaha R6 for HP. But it has 110lbs of torque. The Suzuki M109R is the most impressive mill from the list given.
 
Messages
1,510
Location
Ca USA
The basic term horsepower was invented by the engineer James Watt... He measured his 4 legged pony and deemed one horsepower is 33,000 foot-pounds of work in one minute. All thought it is an arbitrary unit of measure to establish the rate of work of an engine compared to a horse it has made its way down through the centuries and now appears on our dyno charts... Horsing around with 1 hp (which thanks to Watt) equals 33,000 ft·pounds force per·min... now if you hitched up Watt's hay burning pony up to your motorcycle and yelled gitty up... you will not move anywhere near quick as you'd like but you would definitely feel the effect of 33,000 foot pounds of torque in a minute... 6.28 HP... Enough about ponies... back to fuel burning reciprocating engines... now if we take 33,000 foot pounds of torque and spin it just 1 rpm this will gain us 6.28 HP... OK that's better but we're still basically horsing around and that is what Harley Marketing is doing... (33,000 X 1 / 5252 = 6.28HP)
 
Messages
7,553
Location
North America
Originally Posted By: BusyLittleShop
T.... Horsing around with 1 hp (which thanks to Watt) equals 33,000 ft·pounds force per·min... now if you hitched up Watt's hay burning pony up to your motorcycle and yelled gitty up... you will not move anywhere near quick as you'd like but you would definitely feel the effect of 33,000 foot pounds of torque in a minute...
crackmeup thumbsup horse
 
Messages
4,116
Location
Central Virginia
Originally Posted By: BusyLittleShop
The basic term horsepower was invented by the engineer James Watt... He measured his 4 legged pony and deemed one horsepower is 33,000 foot-pounds of work in one minute. All thought it is an arbitrary unit of measure to establish the rate of work of an engine compared to a horse it has made its way down through the centuries and now appears on our dyno charts... Horsing around with 1 hp (which thanks to Watt) equals 33,000 ft·pounds force per·min... now if you hitched up Watt's hay burning pony up to your motorcycle and yelled gitty up... you will not move anywhere near quick as you'd like but you would definitely feel the effect of 33,000 foot pounds of torque in a minute... 6.28 HP... Enough about ponies... back to fuel burning reciprocating engines... now if we take 33,000 foot pounds of torque and spin it just 1 rpm this will gain us 6.28 HP... OK that's better but we're still basically horsing around and that is what Harley Marketing is doing... (33,000 X 1 / 5252 = 6.28HP)
LOL, I really like your posts!
 
Messages
7,553
Location
North America
Originally Posted By: Quattro Pete
Originally Posted By: Kuato
horse
How much horsepower does it take to beat on a dead horse? smile
Some negative value?
 
Top