ok so 300 is easily attainable from what you are saying. that is at the wheels right? what about the torque? am i online with what i asked for torque numbers? what kind of change will the 17*HPOP I have make over retaining the 15* HPOP?

 

Torque doesn't really matter......

but....

You'd be in the 620-640 range DEPENDING on the tuning. If your ICP tanks under load, your torque will be higher and peak sooner (which will cause a peaky horsepower curve); albeit with more smoke and heat.

The high pressure oil pump will only make a difference if you get a healthy 17 degree pump as a worn out one will be a total waste of time.

 

its a new 17*


not trying to insult your intelligence, but torque doesnt matter? please school me on how this doesnt matter.. im not trying to be a dick, im just trying to figure out how it doesnt matter.

 

Just a second. Instead of typing it all out, I have a wonderful explanation for you....

Wait for an edit....

Play with this for a while! It's GREAT! http://craig.backfire.ca/pages/autos/horsepower




---AutoMerged DoublePost---

Torque vs. Horsepower

by Rod Heilfron


I've been reading car and motorcycle magazines for more than 36 of my 52 years and I've always seen articles about Torque vs. Horsepower but I've never seen one that does the subject justice. So I'm going to try to tell you just what is Torque and what is Horsepower. As a note, I’m not going to go into heavy math and rocket science, like how you magnetize a spider in a super magnetic field and suspend it in the air. I’m am going to discuss things just like any backyard mechanic would, with simple math and a good understanding of the laws of physics. I will be simplifying things a bit and I’m not going to go into detail explanations for everything I say. You’ll just have to trust me, honest.


Engine Torque is a measure of the LOAD on a rotating part. As far as motorcycles are concerned it is the load imposed on the primary drive's drive gear, the one attached to the crankshaft. If you over-torque the head of a bolt, you’ll break the head off. If you built an engine with too much torque you’d break the crankshaft or sheer the teeth off of the primary’s drive gear (or some weaker part farther down in the drive train). When you increase the torque of an engine on a pre-made bike you increase all the loads on the clutch, transmission gears, drive chain or belt or shaft and, of course, the rear tire. But when you're designing an engine from scratch all the gear ratios are undetermined and you can't even calculate the load on the clutch from Engine Torque alone because the load on the clutch is equal to Engine Torque times Primary Gear Ratio. As an example, lets make a test bike, with a 1.5:1 primary ratio, a 3.0:1 first gear and a 3.0:1 final drive ratio. If the test engine produced 80 ft lbs of torque the clutch has to handle 120 ft lbs of torque (80 ft lbs times 1.5 primary drive ratio). The output from the transmission in first gear is 120 x 3.0 or 360 ft lbs. The torque is further multiplied by the 3.0 final drive ratio to 1080 ft lbs. Let's say that we loose 20% of our torque do to "transmission losses", we end up with 864 ft lbs of torque at the rear wheel. This is the maximum amount of torque at the rear wheel of our test bike in first gear and will only be available at one rpm, peak torque’s rpm. At all other rpms the torque will be less. Actually, if you rev the engine with the clutch in, then let the clutch out, you’ll have much more torque available for a drag racing launch because the energy stored in the rotating crank, flywheel, clutch, etc. is released as they slow down. The heavier these parts are, the more load you put on the clutch, transmission, drive chain or belt or shaft, the rear wheel spokes, and rear tire. It feels like you have more power but what you’ve done is store a lot of energy in rotating masses and then applied it to the bike all at once. Once the engine and rear tire are running in sync only the engine torque will accelerate you and the extra mass of the flywheel will actually slow you down. It’s impossible to tell the difference between low end torque and heavy flywheel effect when you rev the engine and release the clutch from a stop. Now, to make rear wheel torque useful for calculating acceleration we must convert it into lbs of force at the rear tire’s contact patch by dividing the rear wheel torque by the rear tire radius. So 864 ft lbs divided by 1.0425ft (12.5" radius for a 25" diameter tire) is 829 lbs of forward thrust at the rear tire. If our bike weights in at 500 lbs plus a 200 lb load for fuel and rider, that's 700 lbs of weight. From one of Newton's laws of motion: f = ma or more useful for us: a = f/m. a = 829/700 = 1.18 g's. Now, this means that if the rear tire can handle it at one point during the acceleration in first gear the bike will reach a little over 1g acceleration, kind of like taking a step of off a building's roof, very scary. If we have a 1:1 gear ratio in 5th gear our maximum acceleration will be 80 x 1.5 x 1 x 3.0 / 1.042 x 80% / 700 = .39g's. That's: Engine Torque x Primary Gear Ratio x Transmission Ratio x Final Gear Ratio / Tire Radius x (100% - Transmission Loose) / Weight . And all the gears 2 though 4 will be somewhere in between. Now, in the real world, the maximum acceleration will be much less because we've got to fight the wind. In reality, we’ll get about .8g's in first and .15 to .20g's in high gear, depending on what rpm (and therefore what wind speed) the engine produces that maximum torque figure. Actually, the maximum acceleration will occur at a speed just below maximum torque since lowering the rpms reduces the torque just a little but the reduction in speed reduces the wind resistance by a lot.


Now lets explore the acceleration due to Engine Torque a little more in depth. Lets say we've got 2 identical cruisers with two riders that weigh the same. At 60 mph both bikes make 75 ft lbs of torque and both accelerate around an 18 wheeler at the same time. Now one of the riders believes that acceleration is caused by torque and the more you have the better and he notes that his engine will produce more torque as he accelerates from 2500 rpm if he keeps his bike in 5th gear. The other rider (me) believes that horsepower, not torque, accelerates the bike and he down shifts into 3rd gear, revving to 3900 rpms knowing that all the time he's accelerating, his torque will be decreasing. The first bike accelerates at a pretty constant .2g's to .16g's while the second bike accelerates at first at .3g's slowing to .2 g's as it reaches the top speed available in 3rd gear. This second bike accelerates at a much higher rate even though it’s torque is going down while the torque of the first bike is going up! What's going on? Well, the people that say that Engine Torque is what accelerates a bike forgot about the gear ratios. Rear Tire Force, not Engine Torque, is what accelerates the bike and Rear Tire Force is Engine Torque times all the gear ratios and then modified for the rear tire diameter. Engine Torque only determines the load on the Primary Drive's drive gear, that's all. It's the most misused property of an engine ever. Knowing the torque that an engine produces only tells you it's displacement and nothing about the bike's acceleration unless you know the gear ratios and rear tire diameter. Oh, by the way, in the truck passing example the second bike was able to pass the truck and pull in front of it about 100 feet before it's competition on the first bike, who, unfortunately didn't have an extra 100 feet to spare and became a splat on the front of the 18 wheeler that was coming the other way.


Magazine articles that you've read that say they measured the torque at the rear wheel and got 45 to 120 ft lbs are not telling you the truth. Rear Wheel Torque is 200 ft lbs to well over 1,000 ft lbs depending on what gear the bike was tested in and can not even be measured on a rear wheel dyno. Rear wheel dynos measure Horsepower not Torque, the Engine Torque is calculated from the equation: Horsepower = Torque x RPM / 5252 or Torque = Horsepower x 5252 / RPM. People that claim that horsepower is just the result of a calculation are wrong, the equation just relates different aspects of the engine: Torque, RPM and Horsepower. If you know any 2 of the aspect you can calculate the 3rd. For example if you know the Horsepower and the Torque you can calculate the RPMs, that doesn't make the RPMs just some calculated item. The math is just used to calculate what ever you don't know, with an inertia dyno (rear wheel dyno) you know the RPMs and the Horsepower and you calculate the Engine Torque, NOT the REAR WHEEL Torque.


Engine Torque is about as useless an attribute of a bike as can be. Two equal weight bikes, both make a maximum of 70 ft lbs of torque, which one accelerates faster? Why, the one with the most Horsepower! 70 ft lbs of torque at 5,000 rpms can't beat 70 ft lbs of torque at 10,000 rpms! Why? Because torque times rpms equals horsepower and it is horsepower that moves your bike down the road. You can gear a 10,000 rpm engine twice as low as a 5,000 rpm engine thus doubling the Rear Wheel Torque and therefor the force at the tire contact patch.

 

ok i understand now. thanks.

 

I did find one more example. It takes a while to read, but it really DOES make a lot of sense.

It's one article written (mostly incorrectly) and then countered by a person who understands the concepts

http://www.vettenet.org/torquehp.html