Jump to content

Low bhp yeah but feel the torque bro!


geofferz
 Share

Recommended Posts

6 minutes in, though the first 2 points are interesting too



I've been saying this for years, contrary to popular belief. Especially when I test rode a Harley with loads of torque but joke low rpm therefore sod bhp - I couldn't feel any torque (or anything, just a horrible huge boat between my legs). Now I know why.

 

What year and model may I ask ?

Link to comment
Share on other sites

But he's not saying you can have high torque but low rpm and therefore no bhp.


He's saying torque and bhp are linked. You can't have one without the other. Different engines just deliver their power in different ways. The critical factor is where in the rpm range the usable power is delivered.

Link to comment
Share on other sites

I've ridden with guys on bikes with much higher bhp and we keep pace with each other no problem. Going into a bend I have to brake much earlier them because my brakes are nowhere near as powerful, but I make that up coming out of the corner.

But you only keep up because those guys can't ride (i.e. they're in the wrong gear) :? Of course that's the other side of the coin, most people don't want to work that hard so a nice flat torque curve works well for them and feels more powerful. This is surely why most cars are so blandly tuned..

Link to comment
Share on other sites

I've ridden with guys on bikes with much higher bhp and we keep pace with each other no problem. Going into a bend I have to brake much earlier them because my brakes are nowhere near as powerful, but I make that up coming out of the corner.

But you only keep up because those guys can't ride (i.e. they're in the wrong gear) :? Of course that's the other side of the coin, most people don't want to work that hard so a nice flat torque curve works well for them and feels more powerful. This is surely why most cars are so blandly tuned..

 

'Scuse me!...I am NOT keeping up with them. They are the ones playing catch up. Not that I'm really all that good. Just having a shed load of grunt comes in handy. They've got huge bhp but as you say their gearing means they're only just getting near it by the time the next corner comes along.


'Course I choose the route wisely. No long straights where they'd gobble me up.

Link to comment
Share on other sites

Torque is largely a function of engine size and power is essentially just torque x revs.


Engine configuration has little effect on torque and a V twin is not inherently more torquey than an inline 4.


A 600cc engine is a good illustration of how it works. A 600 could be a single, twin, triple or 4 cylinder.


All would make much the same torque (around 40 ft lbs). However they would have very different power outputs.


The single would red line around 6000rpm and make approx 45 bhp

The twin would rev to around 9000rpm and make around 65 bhp

The triple would go higher still and make around 90 bhp

The four might rev up to 15,000rpm and make well over 100bhp


In riding, they would feel very different. The single would feel quickest off the mark. Open the throttle, even a bit, and it feels like it wants to leap away. The four would feel flaccid low down with nothing much happening below 8,000rpm but at higher revs would leave the single for dead.


Can you really “Feel the torque”? Probably not. Most “High torque” motors develop all of their power and torque within a narrow range at low revs. Open the throttle and wham, it's right there. But try to rev the thing and you find that it has nothing more to give.

Link to comment
Share on other sites

They've got huge bhp but as you say their gearing means they're only just getting near it by the time the next corner comes along.

 

They should be 3 gears lower..

 

Exactly. Riding where you should be, in the power band, and torque is irrelevant - higher bhp wins.


Of course in the twisties with all bikes doing 40mph it'll be pretty close regardless.

Link to comment
Share on other sites

6 minutes in, though the first 2 points are interesting too



I've been saying this for years, contrary to popular belief. Especially when I test rode a Harley with loads of torque but joke low rpm therefore sod bhp - I couldn't feel any torque (or anything, just a horrible huge boat between my legs). Now I know why.

 

What year and model may I ask ?

 

2019 Fat Bob Screenshot_20200111-134415_Photos.thumb.jpg.7a768d56d971db12a33cc87b2cf5daf1.jpg

 

Also I'm not dissing harleys - I'd quite like one - they are undeniably cool. But they are simply not fast compared to any bike with 70bhp or more.


I just think we should stop talking about torque cos it means nowt and you can't feel it!

Link to comment
Share on other sites

6 minutes in, though the first 2 points are interesting too



I've been saying this for years, contrary to popular belief. Especially when I test rode a Harley with loads of torque but joke low rpm therefore sod bhp - I couldn't feel any torque (or anything, just a horrible huge boat between my legs). Now I know why.

 

What year and model may I ask ?

 

2019 Fat Bob Screenshot_20200111-134415_Photos.jpg


Also I'm not dissing harleys - I'd quite like one - they are undeniably cool. But they are simply not fast compared to any bike with 70bhp or more.


I just think we should stop talking about torque cos it means nowt and you can't feel it!

 

That's a big brute of bike . I'm not even going down the " Sportsters are quicker than Big Twins " debate but mine has been a joy and a revelation since I got it . It easily reaches 100 MPH and I've never asked any more of it but that's not what I got it for .It's been years since I've felt such a craving for summer to arrive . Forget BHP , RPM and torque it's about FUN !

Link to comment
Share on other sites

I've ridden with guys on bikes with much higher bhp and we keep pace with each other no problem. Going into a bend I have to brake much earlier them because my brakes are nowhere near as powerful, but I make that up coming out of the corner.

But you only keep up because those guys can't ride (i.e. they're in the wrong gear) :? Of course that's the other side of the coin, most people don't want to work that hard so a nice flat torque curve works well for them and feels more powerful. This is surely why most cars are so blandly tuned..

 

'Scuse me!...I am NOT keeping up with them. They are the ones playing catch up. Not that I'm really all that good. Just having a shed load of grunt comes in handy. They've got huge bhp but as you say their gearing means they're only just getting near it by the time the next corner comes along.


'Course I choose the route wisely. No long straights where they'd gobble me up.

 

Probably down to the same effect you see on F1 cars as they pull out a corner, the car in front gets on the gas half a second ahead of the trailing car so appears to pull away.

Link to comment
Share on other sites

It's pretty obvious that [mention]geofferz[/mention] is talking about riding fast/racing here and this is where BHP is needed as you keep the revs sky high all the time and in the peak power


But BHP and torque are two different power curves and act differently and both have their own uses


If you want a bike to accelerate and be fast you need high BHP


If you want it to pull hard then you want high torque


This is why race bikes are higher revving higher bhp and lower torque than say a touring bike that is designed for lugging loads around all day long!


This is where the "feel" of torque comes from as you can feel the bike pull you along effortlessly


Gearing on a bike has a massive impact on how that bike performs and as I said previously if you could have the same bike but change the torque and bhp without affecting each other then you would feel the difference


having a good balance of both is the key but then that all depends on the application of the bike


this isn't a bad read https://www.tvsmotor.com/blog/power-vs-torque-differences-explained-and-how-the-two-quantities-affect-a-vehicles-performance/

Link to comment
Share on other sites

It's pretty obvious that @geofferz is talking about riding fast/racing here and this is where BHP is needed as you keep the revs sky high all the time and in the peak power


But BHP and torque are two different power curves and act differently and both have their own uses


If you want a bike to accelerate and be fast you need high BHP


If you want it to pull hard then you want high torque


This is why race bikes are higher revving higher bhp and lower torque than say a touring bike that is designed for lugging loads around all day long!


This is where the "feel" of torque comes from as you can feel the bike pull you along effortlessly


Gearing on a bike has a massive impact on how that bike performs and as I said previously if you could have the same bike but change the torque and bhp without affecting each other then you would feel the difference


having a good balance of both is the key but then that all depends on the application of the bike


this isn't a bad read https://www.tvsmotor.com/blog/power-vs-torque-differences-explained-and-how-the-two-quantities-affect-a-vehicles-performance/

 

But I don't think 'pull hard' is a thing? The super torquey harley I rode didn't pull hard.

Link to comment
Share on other sites

It's pretty obvious that @geofferz is talking about riding fast/racing here and this is where BHP is needed as you keep the revs sky high all the time and in the peak power


But BHP and torque are two different power curves and act differently and both have their own uses


If you want a bike to accelerate and be fast you need high BHP


If you want it to pull hard then you want high torque


This is why race bikes are higher revving higher bhp and lower torque than say a touring bike that is designed for lugging loads around all day long!


This is where the "feel" of torque comes from as you can feel the bike pull you along effortlessly


Gearing on a bike has a massive impact on how that bike performs and as I said previously if you could have the same bike but change the torque and bhp without affecting each other then you would feel the difference


having a good balance of both is the key but then that all depends on the application of the bike


this isn't a bad read https://www.tvsmotor.com/blog/power-vs-torque-differences-explained-and-how-the-two-quantities-affect-a-vehicles-performance/

 

But I don't think 'pull hard' is a thing? The super torquey harley I rode didn't pull hard.

 

Then you are riding it wrong :wink:


It takes time to learn where the power is and how to use it to its fullest


When I first got the TL I tried to ride it like my old gsxr 600 and I was bouncing it off the rev limiter and it felt awfully slow! it took me months to get the hang of it I was trying to ride it at 8.5 -9k all the time and this is where the torque drops off you need to be closer to 6.5k


you feel like you are short shifting on big twins you don't rev them out


As I say its all about the pull in that they will pull in practically any gear where as something with half the torque you will need to down shift at least two gears! they wont shoot off but they will pull away keeping the bike on that torque curve is the key when riding about but when racing you keep it at peak BHP

Link to comment
Share on other sites


But I don't think 'pull hard' is a thing? The super torquey harley I rode didn't pull hard.

 

You can certainly feel the hard pull on the current generation of Triumph twins. If I twist the throttle too enthusiastically it is actually quite hard to stay in the seat. The wrench on your arms is pretty brutal. I have seen a video of a guy who disabled the traction control and I'm not even going to think about trying that.


It has six gears but really you only ever need the first four. Fifth on a motorway. Sixth must be for places with no speed limit.


If you have a Triumph dealer nearby ask for a test ride on anything with the 1200 twin in it.

Link to comment
Share on other sites

When I swapped the exhaust on my s1000rr the low speed torque suffered due to eliminating the various exhaust valves but the top end bhp increased due to free flowing exhaust with no catalytic converter.

Dropped a tooth off the front sprocket to move the gearing to be higher revs at lower speed and the bike became ballistically quick all the way through the range. Extra wheelie happy too 👍

Link to comment
Share on other sites

My understanding is that you feel torque when you realise that your bike feels as quick with just you on it, as it is carrying the extra weight of a pillion and you keep on finding yourself in a higher gear than you thought. Torque is about pulling weight.

Link to comment
Share on other sites

Not sure if this thread is classed as 'dead', but I felt like throwing in my own view.


What he's saying in the video is that BHP is directly derived from Torque. One is essentially just another way of expressing the other. You can't feel the difference because they are both the same thing. Just like 1 is identical to 0.5 + 0.5.


The only question is, whereabouts in the rev range do you find the torque? You can always manually draw the BHP line on any graph that already has the Torque and RPM measured: Torque * RPM / 5252... and vice-versa, just reverse the equation.


When we say something is 'Torquey' what we usually mean is that it has high Torque low down in the rev range, or a more even/flat torque curve. When we say something has 'high bhp but low torque' (a 600 inline 4 or maybe a 125cc 2-stroke) what we actually mean is that it has its peak torque higher in the rev range. As bhp is just Torque * RPM / 5252 this means that it's pulling power lies much higher in the rev range than down low.


Ultimately, it is impossible to actually feel the difference between torque and bhp, they're both the same thing. All you can feel is the bikes ability to pull weight (itself and you) across a rev range. And that isn't the difference between bhp and torque, it's just feeling the torque curve.

Link to comment
Share on other sites

I did not think the difference would be that big!

 

Its not!


two totally different kettles of fish there!


Ones a slow cruiser and most are tuned drag bikes by the looks of it!


Not a good comparison

Link to comment
Share on other sites

There's a lot of horseshit in this thread.


Firstly, that 2 minute (bad)explanation in the linked video is a rip off from The Workshop - look him up on YouTube, he did a series of 3 or 4 videos explaining torque and bhp.


Secondly, torque (as quoted by manufacturers, racers, journalists, etc) is a construct for advertising purposes.

It's not a real thing. Torque is a turning force at a given distance from a rotation centre or fulcrum. Singles and twins generally have a longer stroke and a bigger "bang" per piston than a four of similar displacement, so the torque will be higher.


Thirdly, BHP (as quoted by etc etc) is a construct for advertising purposes, using a calculation from torque & revs. And the more revs an engine can do, the more BHP can be created. Fours can generally rev faster than twins because they have shorter, wider (oversquare) stroke.


So basically, a "torquey" engine gives it's best performance at low to medium engine speeds and a high BHP or revvy engine gives it's best performance at high engine speeds. And in the real world that's all you need to know - peak torque and Max BHP numbers are largely irrelevant unless you are a bike racer, bike maker/seller or a twelve year old fan-boy


I recommend going to Matt's channel: The Workshop, and search for the Torque series - the guy is an engineer who understands how engines work, and explains it all really well. Be warned, he smokes and swears on camera - some people are offended by that

Link to comment
Share on other sites

There's a lot of horseshit in this thread.


Firstly, that 2 minute (bad)explanation in the linked video is a rip off from The Workshop - look him up on YouTube, he did a series of 3 or 4 videos explaining torque and bhp.


Secondly, torque (as quoted by manufacturers, racers, journalists, etc) is a construct for advertising purposes.

It's not a real thing. Torque is a turning force at a given distance from a rotation centre or fulcrum. Singles and twins generally have a longer stroke and a bigger "bang" per piston than a four of similar displacement, so the torque will be higher.


Thirdly, BHP (as quoted by etc etc) is a construct for advertising purposes, using a calculation from torque & revs. And the more revs an engine can do, the more BHP can be created. Fours can generally rev faster than twins because they have shorter, wider (oversquare) stroke.


So basically, a "torquey" engine gives it's best performance at low to medium engine speeds and a high BHP or revvy engine gives it's best performance at high engine speeds. And in the real world that's all you need to know - peak torque and Max BHP numbers are largely irrelevant unless you are a bike racer, bike maker/seller or a twelve year old fan-boy


I recommend going to Matt's channel: The Workshop, and search for the Torque series - the guy is an engineer who understands how engines work, and explains it all really well. Be warned, he smokes and swears on camera - some people are offended by that

 

Ryan from Fortnine is a sublime presenter, I highly doubt he would plagiarise anything. I tried to watch matt once, the swearing made me turn off. My point is simply that you can't 'feel torque' and that bhp is the only important figure. Of course where its made is key too. Bhp IS important - I wanted to buy a new bike and rode some bikes with less power than mine... Too slow for me. As much as I wanted a new toy I couldn't go down in performance.

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

 Share

  • Welcome to The Motorbike Forum.

    Sign in or register an account to join in.

×
×
  • Create New...

Important Information

Terms of Use Privacy Policy Guidelines We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue.

Please Sign In or Sign Up