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[bigjohn]

or forget it all and imagine a nitro harley shifting and making 500 hp @ 5000 rpms. better have bigger "ONES" than "A" Big dyno sheet.
of course this is always true in any race. big ONES win out.

Bingo..................whats that song..." no fear..no doubt....all in balls out". That says it all. Did you see that 2.8 dyno run on htt.....that would take huge ones.

[strokerjlk]

Bingo..................whats that song..." no fear..no doubt....all in balls out". That says it all. Did you see that 2.8 dyno run on htt.....that would take huge ones.

 yeah even on the street,it is the same. most times on 50-60 mph rolls the one that gets the jump is the one out front. it is then just a matter of who can stay in it the longest. most guys wont run past 110-120 mph anyway.
seen that video 
dead stop races.....where your tq. peaks dosent mean squat. your @ 6000 rpms in no time,then hp to weight wins out.

[Steve Cole]

dead stop races.....where your tq. peaks dosent mean squat. your @ 6000 rpms in no time,then hp to weight wins out.

You might get to 6000 in no time in first gear but it takes Torque to pull the weight of the package up to speed in the higher gears, so unless your a stop light racer a High RPM HP motor will lose hands down to a High Torque package on a heavy touring bike. Sure once your up to speed in high gear HP will win but getting there is another thing. Kind of like trying to state a dyno run is anything close to real world. I would love to see anything with an HD engine go out on the road and run from  starting point to ending point in the same ET as it does on the dyno. Most dyno pulls are 5 - 6 second from start to finish. So go put your bike on a flat road and be in 5th gear at 2000 RPM and open it up, then hold it until you reach 6000 RPM and tell me if it's anywhere close to 5 - 6 second. Most would be lucky to do it in 25 seconds! It's Torque that pulls it up to speed not HP, HP is what keeps it there!

[HILLSIDECYCLE.COM]

Torque being a "twisting motion", so the sooner and longer the twisting motion can be maintained, the greater the rate of acceleration.
Scott

[Arctic John]

I'm one of the uneducated guys here...but thanks to all of you for the comments. 

This site is awesome !!

[Spiderman]

I guess until everybody says it in their own words, we're gonna say the same thing 100 times.

B B

[bigjohn]

"it takes Torque to pull the weight of the package up to speed in the higher gears, so unless your a stop light racer a High RPM HP motor will lose hands down to a High Torque package on a heavy touring bike. Sure once your up to speed in high gear HP will win but getting there is another thing."

I think we all agree on that.

Kind of like trying to state a dyno run is anything close to real world.

Thats what I have been saying. Dyno's are good tools to use and thats about all. There are to many variances in dyno sheets when it comes to trying to live and die by the numbers. Everyone knows dyno's can be over inflated or under inflated numbers. Thats why I never get excited when I see numbers. Now show me the before and after on the same dyno, that is something to work with.

It's Torque that pulls it up to speed not HP, HP is what keeps it there!

Thats the text book answer..........along with what scott is defining as torque.
I think thats what we were discussing.

I think he was referring to hp/weight ratio. Which he is right when it comes to the track (hyabusa vs HD). Their ratio is ideal. (at least thats how I took it)

dead stop races.....where your tq. peaks dosent mean squat. your @ 6000 rpms in no time,then hp to weight wins out.

[strokerjlk]

Torque being a "twisting motion", so the sooner and longer the twisting motion can be maintained, the greater the rate of acceleration.
Scott

no fair Scott.......you know/knew one is dependant on the other

[Steve Cole]

Where your torque peaks means everything for a dead stop race! Let's look at how it turns out, torque rises to the point that it begins to fall as you climb through the RPM range. So if you have peak torque in the RPM range you ride then you are able to get the load moving as quick/fast as possible as Scott has said. If peak Hp is at 6200 RPM you have to get there first then keep it there so unless you gear the bike for racing your going to get your a$$ handed to you by someone who knows how to ride and has the Torque where it needs to be for the size and weight of the bike.

As a rule of thumb you shift at peak Hp as long as the gear change does not drop you down below peak Torque. This is the starting point to figure it all out but what most people miss it the simple fact that you have to get it all up to speed for the HP to carry it along. Look at any form of racing and you can see how long it takes to get up to speed but once they get there they can hold it. Indy cars make very little torque but great HP at 14,000 RPM but that's what a short stroke motor does. A HD engine is anything but a short stroke motor! Its built to make big torque at lower RPM's. How many here really race there CVO? Most are daily riders and may tow a trailer where big low RPM torque is going to rule. I tell most HD riders to take the dynosheet and fold it right at 4500 RPM, so one side shows everything below and the other everything above. The low side is what you use day in and day out, while the other side may get used once every few months. So which would you want to build for?

[strokerjlk]

back to drag race

so what would we rather have in a drag race? we were talking  time.. tq vs hp. @ rpm
same bike two diff motors one that makes  75 tq 100hp @ 6000 rpms? or one that made 50 tq 125 hp @ 7000 rpm.?

[Half_Crazy]

If I may, let's look at the two opposite ends of the HP vs Tq spectrum.

The GSXR 600 by Suzuki makes around 100 HP and 46 ft-lbs of torque, weighs 400 lbs wet, and will do the 1/4 mile in 11.0-something.

The way my bike was before it made 120 HP and 131 ft/lbs, weighs 720 lbs wet, and would get down the 1/4 mile in 11.7-something.

So... in a drag race, I would lose by almost 3/4 of a second.... However, when the two of us are riding together on the road it's a totally different story. He has no torque and needs to run the crap out of that thing to stay with me, even if I'm short-shifting. Every time we accelerate off a light or make a pass he feels like he's outgunned. In order to accelerate with any authority he must keep the engine in its "powerband" which starts at 10,000 RPM. My bike didn't have a "powerband" and made 100 ft-lbs by 2200 RPM.

I actually did play around with one of those on the street. On one occasion under hard acceleration he closed the throttle when in front of me... I couldn't hear his quiet bike... and I almost ran right over him! Unless he's willing to ride around at 11,000 RPM, he's playing catch-up all day long.

This is also why I'm not a big fan of the V-Rod. The fun starts at around 5000 RPM on one of those. Doesn't suit my riding style.

  

[strokerjlk]

If I may, let's look at the two opposite ends of the HP vs Tq spectrum.

The GSXR 600 by Suzuki makes around 100 HP and 46 ft-lbs of torque, weighs 400 lbs wet, and will do the 1/4 mile in 11.0-something.

The way my bike was before it made 120 HP and 131 ft/lbs, weighs 720 lbs wet, and would get down the 1/4 mile in 11.7-something.

So... in a drag race, I would lose by almost 3/4 of a second.... However, when the two of us are riding together on the road it's a totally different story. He has no torque and needs to run the crap out of that thing to stay with me, even if I'm short-shifting. Every time we accelerate off a light or make a pass he feels like he's outgunned. In order to accelerate with any authority he must keep the engine in its "powerband" which starts at 10,000 RPM. My bike didn't have a "powerband" and made 100 ft-lbs by 2200 RPM.

I actually did play around with one of those on the street. On one occasion under hard acceleration he closed the throttle when in front of me... I couldn't hear his quiet bike... and I almost ran right over him! Unless he's willing to ride around at 11,000 RPM, he's playing catch-up all day long.

This is also why I'm not a big fan of the V-Rod. The fun starts at around 5000 RPM on one of those. Doesn't suit my riding style.

  

I raced a busa, with my bagger. 1/8 mile. I turned a 8 and he turned a 7. I had him at 60 ft and 300 ft. after that he came around me like I was sitting still. 3/4-1 sec is eternity in the 1/8 th.
I did holeshot him though. pretty bad. dont think he really cared. he just didnt want to red light and lose to a geezer glide.

[Half_Crazy]

I raced a busa, with my bagger. 1/8 mile. I turned a 8 and he turned a 7. I had him at 60 ft and 300 ft. after that he came around me like I was sitting still. 3/4-1 sec is eternity in the 1/8 th.
I did holeshot him though. pretty bad. dont think he really cared. he just didnt want to red light and lose to a geezer glide.

It was the rider. I have seen stock 'Busas do 1.45 second 60 foot times... That's QUICK. My best 60' was 1.73

Personally, I much prefer 1/4 mile racing. In the 1/8 mile, just when it's getting fun, it's over. In the 1/4 I was going thru the traps at 5000 RPM in 5th gear. I'm hoping that with the 6700 RPM limiter and the bike making power out past 6200... I can stay in 4th all the way.

[Steve Cole]

If I may, let's look at the two opposite ends of the HP vs Tq spectrum.

The GSXR 600 by Suzuki makes around 100 HP and 46 ft-lbs of torque, weighs 400 lbs wet, and will do the 1/4 mile in 11.0-something.

The way my bike was before it made 120 HP and 131 ft/lbs, weighs 720 lbs wet, and would get down the 1/4 mile in 11.7-something.

So... in a drag race, I would lose by almost 3/4 of a second.... However, when the two of us are riding together on the road it's a totally different story. He has no torque and needs to run the crap out of that thing to stay with me, even if I'm short-shifting. Every time we accelerate off a light or make a pass he feels like he's outgunned. In order to accelerate with any authority he must keep the engine in its "powerband" which starts at 10,000 RPM. My bike didn't have a "powerband" and made 100 ft-lbs by 2200 RPM.

I actually did play around with one of those on the street. On one occasion under hard acceleration he closed the throttle when in front of me... I couldn't hear his quiet bike... and I almost ran right over him! Unless he's willing to ride around at 11,000 RPM, he's playing catch-up all day long.

This is also why I'm not a big fan of the V-Rod. The fun starts at around 5000 RPM on one of those. Doesn't suit my riding style.

  

Now just think what would happen if you could drop that extra 320 lbs of weight off the HD!

[Dr.D]

Thanks for the lively thread guys I did not see a southward turn. Spirited discussions among passionate fellows that all love motorcycles.

Please remember that in the stream of knowledge there will always be guys behind and ahead of you. IMHO. My questions were answered very well and I appreciate you all. Next time I hear a big dyno bragger I can rest that there is more to a ride than it's numbers. I love my 120ft/lbs and glad that I don't have to live at 6K+.

Love live the beefy fat over weight HD.