Provisional Thursday Morning AMA Superbike Practice Times:
Tommy Hayden (Kaw ZX-10R), 1:40.045
Provisional Thursday Morning AMA Supersport Practice Times:
Tommy Hayden (Kaw ZX-6RR), 1:41.590
closer comparision would be sport to fx or stock to bike or sport to stock or fx to bike
bike to sport is not real close comparision different level of modification allowed and displacement difference.
I think Dave's point is that you have a bike that makes 125-135 hp and one that makes 200+ and the difference in lap times at a horsepower track like Daytona is only 1.5 seconds...
Eric's point is that the comparison is more than power. To compare what difference power makes, you should compare two bikes that are identical other than their power output. Comparing a supersport bike to a superstock bike is much more than a power difference.
I guess you are right. I have heard that the ZX-10's do handle like crap...
QuoteEric's point is that the comparison is more than power. To compare what difference power makes, you should compare two bikes that are identical other than their power output. Comparing a supersport bike to a superstock bike is much more than a power difference.
+1000 !
I've seen this raging debate and it makes me chuckle. All other things equal, HP wins races. If you take identical bikes in every respect except one makes 20 HP more than the other, the higher HP one wins every time (with the same rider).
I understand that there are MORE important things if you're starting from scratch, but with the bike straight up and down to say that HP isn't a huge advantage is silly.
The ZX6-RR is a developed motorcycle, moreover one that both Haydens are very familiar with. The ZX10 is not. The ZX10 also has a lot of new pieces this year.
I think a better comparison is Mladin's / Spies GSXR superbike vs. an average superstock bike.
Mladin GSXRK6 sb 1:37.075 (Good GOD!)
May GSXRK6 ssk 1:39.712
2.7 seconds a lap is an enternity, even at DIS. I agree you should start from the pavement and work your way up when doing mods, but power does matter
QuoteEric's point is that the comparison is more than power. To compare what difference power makes, you should compare two bikes that are identical other than their power output. Comparing a supersport bike to a superstock bike is much more than a power difference.
And my point is further...
If you read my original post...
It's a Superbike vs Supersport bike.
So, not only are we dealing with HP, the superbike probably has 40% more than the supersport bike, it has lighter wheels, aftermarket brakes, slicks, aftermarket forks, etc.
Controling with the rider, the difference is not big. 1.5 seconds can be big, but with a bike that is spinning on the banking for such a long time...HP can make up a whole lot in that "straightaway" area.
Not developed? Spare me. No bike ever reaches a final stage of development in the production world. You're always making changes. How much money has Kaw put at the ZX10R? Are they there to parade around or actually try and win the championship? Businesses are not out for fun.
QuoteAnd my point is further...
If you read my original post...
It's a Superbike vs Supersport bike.
Yes I read the original post, you listed the lap time for 2 different bikes under the heading 'hp vs lap times' with no furthur text.
QuoteSo, not only are we dealing with HP, the superbike probably has 40% more than the supersport bike, it has lighter wheels, aftermarket brakes, slicks, aftermarket forks, etc.
Controling with the rider, the difference is not big. 1.5 seconds can be big, but with a bike that is spinning on the banking for such a long time...HP can make up a whole lot in that "straightaway" area.
Not developed? Spare me. No bike ever reaches a final stage of development in the production world. You're always making changes. How much money has Kaw put at the ZX10R? Are they there to parade around or actually try and win the championship? Businesses are not out for fun.
Why not compare to Mladin's time then. What was that, in the low 37s. That would be more like 4 seconds faster. Really doesn't matter because it is still apples to oranges.
If you want to make a definitive statement about the affect of hp on lap times, you still need to compare 2 bikes, same rider with the only difference between the bikes being power.
a better way to approach this issue is to look at segment times:
tommy hayden best segment times
SB qualifying:
11.991
48.132
12.854
25.382
SS qualifying
12.134
48.518
13.609
27.539
So segment 1 and 2 are infield sections so the HP just barely passes the handling of the 600, but look at the run down the back straight and from the chicane to turn 1, HP rules.
you want to see what HP means on the straight?
My best seg 4 time is 29.0 and my bike dyno'ed 106 at the track thur. so apparently the 25+ hp equals to 1.5 seconds from the chicane to turn 1.
which actually makes sense because the superbike have what 60+ hp and it is over 2 seconds faster than the SS bike. Of course the drag efficiency of the bikes and the fact the SB tires spin on the banking still have to be figured in but it seems just about right.
QuoteI've seen this raging debate and it makes me chuckle. All other things equal, HP wins races. If you take identical bikes in every respect except one makes 20 HP more than the other, the higher HP one wins every time (with the same rider).
All things can't be equal though. Horsepower has side effects. I went from an 99 R6 to a 03 GSX-R1000. The 1000 is lighter, makes tons more power and stops better, but I went slower on it. It's just hard to ride with all the motor.
If we raced at elkhart five times a year I'd love it, but at blackhawk or gingerman, I'll take a 600 any time.
QuoteAll things can't be equal though. Horsepower has side effects. I went from an 99 R6 to a 03 GSX-R1000. The 1000 is lighter, makes tons more power and stops better, but I went slower on it. It's just hard to ride with all the motor.
If we raced at elkhart five times a year I'd love it, but at blackhawk or gingerman, I'll take a 600 any time.
You make a point, I suffered through the same exact thing but I'm now much quicker on the R1 than I was on the 600rr. I guess "all things equal" would include a rider that is comfortable with both bikes.
OK, but a bike with 50 HP less than the 600 will have a much bigger difference in lap times. An SV at Daytona would be farther behind a 130 HP 600 than a 600 would be behind a 200+ HP 1000.
But point is still made. HP isn't always as big a diff as most people make it to be. It's just that the 600 is a lot closer to the tire limits of accel. So a 1000 can't add a whole lot more. An SV doesn't have that power.
I guess I could just say that it's not linear.
One more thing to note on your remark there Nate. I am not sure exactly why, but you can have a 95 hp SV and a 95 hp F3 and the F3 will be faster on the straights. I think it has to do with how fast a 4 cylinder bike spools up compared to a twin. I know this from our team running SV's at Brainerd. The inline 4's would come flying by you once the drive out of the corner was nullified.
Now that's interesting. TZracer, or anyone else have any input as to why? Torque curve? Regardless, the I4 can do the same amount of work as the Twin if they're both 95 HP. Is there a reason for this other than gearing?
Inertia (rotational) - crank, transmission, clutch, sprockets, rear wheel/tire. Less energy tied up in rotation, more energy for translation.
There is a trade off (as with most everything) having less inertia in the system. When the tire breaks loose, a bike with less inertia will spin up faster making it more difficult to control - even worse in the rain. Eddie Lawson had Cagiva add mass to the crank of its GP bikes to make them easier to ride.
But if more energy is tied up in the twin, then how can they do the same amount of work? How do you measure this difference? Don't they have the same amount of HP available at the crank?
Let me put it this way: If you remove some weight from the crank, doesn't the bike then make more power on the dyno?
QuoteBut if more energy is tied up in the twin, then how can they do the same amount of work? How do you measure this difference? Don't they have the same amount of HP available at the crank?
Power is the rate at which work is done. 2 engines, same power, same rate of work. Work is converted to energy. For a given amount of time, both engines will do the same work, and hence the same TOTAL energy. The energy (kinetic) is divided up between rotating parts and moving the entire motorcycle from a to b. If you have less rotational inertia, less energy is tied up in rotating parts, which leaves more for translational kinetic energy, then the motorcycle will accelerate at a higher rate.
QuoteLet me put it this way: If you remove some weight from the crank, doesn't the bike then make more power on the dyno?
Lighter crank should make no more power, but the engine will spin up (accelerate) faster. If your dyno is using the rate at which the engine accelerates (inertial dyno) to calculate power, the dyno can read an increase. But is it really an increase in power or a poor way of measuring power?
If you lighten the drum of an inertial dyno, will your power reading change? Did your power really change?
But we're talking about power available at the crank. (as in, measured on a dyno) Sure the power didn't change at the piston head, but the available power is AFTER those rotating parts. The power made at the piston head doesn't mean much if the losses between the piston and crank output are different between 2 engines.
I guess it must come down more to the area under the torque curve. Sure they both make 95 HP at X rpm, but the 600s torque curve may have a lot more area under it, meaning you spend more time closer to that peak while accelerating than the SV would.
QuoteBut we're talking about power available at the crank. (as in, measured on a dyno) Sure the power didn't change at the piston head, but the available power is AFTER those rotating parts. The power made at the piston head doesn't mean much if the losses between the piston and crank output are different between 2 engines.
It depends upon the dyno. An inertial dyno will show more power from a lighter crank, but it will also show more power from lighter wheels.
A brake dyno (one type is an eddie current dyno such as a Factory Dyno) will show no power increase due to a lighter crank.
Power is measured differently on the 2 types of dynos.
Neither type will show a power increase for making your bike lighter (non rotating parts).
So the question is what is the best definition of power? A lighter crank will increase acceleration, but not top speed - no increase in peak power. So does a lighter crank really increase power?
The way I view it, if it does not show up on a steady state dyno run (brake dyno), but shows a change on a inertial dyno, your power was not increased, but your mod will help acceleration. Neither dyno replicates the load placed on the bike while actually accelerating. I do not consider one type better than the other, they (can) tell you different information - you just have to know how to listen.
Perhaps for racing an inertial dyno is better. You can indirectly regulate modifications to the driveline besides power modifications. A smart tuner would know that some mods will not increase the dyno output on a brake dyno, but would on an inetial dyno. One could make these mods without going over the hp limit, yet have a faster bike.
I look at engine/driveline mods in 2 categories, ones that increase power (brake dyno) and ones that increase acceleration (inertial dyno).
???
tzracer you're hurting my head again.
QuoteThe way I view it, if it does not show up on a steady state dyno run (brake dyno), but shows a change on a inertial dyno, your power was not increased, but your mod will help acceleration.
This statement reads that increase in available torque will increase acceleration but not power. One of these days I will find a satisfactory connection between HP, torque and acceleration.
Now where did I put that tylenol........
think of it this way,
on an inertia dyno before the lighter wheels/tires/flywheel/crank etc it took 5 seconds to accelerate from 3,000rpm to 13,00rpm, with the lighter rotating parts the same run takes 4 seconds.
now if you think about the inertia dyno measuring distance over time you can also compare that to coming out of a corner and accelerating down a straight. before if it took you 10 seconds to accelerate down the straight (changing gears as you go) now with the lighter components it may only take you 8-9 seconds.
but like it was mentioned there is no direct comparison between the dyno and on the track.
there are other things that come into play as well, like the bigger 190/55 (or 190/60) tires are a lot heavier than the 180 tires and on the dyno the 190 tires show a hp loss, but if you can get on the gas a lot quicker and have more grip on the 190 tire the acceleration you lost with the heavier tire, is offset but the fact that you accelerated earlier in the corner
Quote??? tzracer you're hurting my head again.
Not me!!
PLEASE keep it up!
I'm just lovin' and learning from threads like this and the "Pounds and Horsepower" a while ago. 8)
I never learned physics in HS nor college. Looking back, I've regreted not having had the practical, intellectual exercise.
Though I wonder whether I would have felt that way back then when a grade would have been on the line. ;D
Quote???
tzracer you're hurting my head again.
That is my job, according to my students I am pretty good at it.
QuoteThat is my job, according to my students I am pretty good at it.
I'll say, Point tzracer.... ;D