| Author | Message | ||
     Mikej |
That would have been interesting if at the 100th if Hal's could have rounded up an XB9 and an XB12 and run them head-to-head on the Ter....si (sp?) drag dyno. They did get a guy with a 'busa to run, hit a 7.2something at 140something for the quarter with 125 or so hp, and a top in the half mile of 178.something. They also had a couple of BossHogs run. The 500hp small block did way better than the 'busa but I forget the speeds and times, the 1000hp big block busted his belt when he whacked the throttle, and the 350hp small block ran a low 7's. This probably has little to do with the discussion, but it was fun to watch. Sometimes it's hard to know what to take literally and what to ignore. Back to my own corner of the world. | ||
| Elvis |
Well, the 12 doesn't spin as fast as the 9, and yet it has more power, right? Everything isn't equal. They have different gearing. That was the point of the statement. If the gearing and everything else is equal, the more powerful engine has to, absolutely, no questions asked, write this down in stone, spin faster. As I said, if it doesn't, it's not more powerful. edited by elvis on September 03, 2003 | ||
| Aaron |
"If the gearing and everything else is equal, the more powerful engine has to, absolutely, no questions asked, write this down in stone, spin faster." XB12: 103hp@6800rpm XB9: 92hp@7500rpm Which engine is spinning faster? Which engine is making the most power? Are you saying that this is only possible because the gearing is different? So if we stuck the 9's primary drive onto the 12, somehow the 12's power would drop below the 9's? Or somehow the 12's engine would be able to turn more rpm than the 9? | ||
| Uwgriz |
Actually, it can spin slower with more torque and be more powerful. This is in fact the case. Otherwise you wouldn't need a dyno, a tachometer would do the trick. Give both bikes the same gearing and the 9 is theoretically a faster (not quicker) motorcyle. | ||
| Aaron |
Uw is right ... Power is torque x rpm. It's entirely possible for a motor to have less rpm, more torque, and be more powerful. That's exactly the case when comparing the 12 and the 9 ... the 12 turns less rpm and yet makes enough more torque that it's power comes out greater anyway. The gearing has nothing to do with it, it's all downstream. You cannot simply ignore torque in the power equation and draw a straight line between power and rpm, torque is half the answer. | ||
| Elvis |
Aaaaaaaaaaaaaaahhhhhhhhhhh!!!!!!! Let me say it again: Everything isn't equal. If the gearing and everything else is equal, the more powerful engine has to, absolutely, no questions asked, write this down in stone, spin faster. That's a simple fact. Forget about XB9S, XB12S, gearing, flywheels etc. if EVERYTHING is equal, a more powerful engine (and I don't care if it's an internal combustion engine, hamster powered, or a rocket engine) will have to spin faster than a less powerful engine under the same load conditions. Work equals power times time. If an engine has more power, it has to do more work or it has to do it quicker. Since we are keeping EVERYTHING but the speed constant, the more powerful engine has to do the work quicker or it is not more powerful. | ||
| Steve_a |
Aaron, it gets interesting when you really try to model acceleration in a computer program. You have to account for all the energy sinks, which are, in descending order of importance, vehicle bulk inertia (weight, in other words), aerodynamic drag, crank inertia, clutch inertia, wheel inertias, and rolling drag. For racing, you try to minimize all of these -- build the lightest vehicle, with the lowest frontal area and best drag coefficient, with the lightest crank, clutch and wheels. Rolling drag you don't worry about because most of that is from the tires, and traction is so much more important that you don't even consider optimizing tires for drag. Crank inertia may or may not be minimized because it becomes a rider control issue. For road-racing, with gumball tires, you don't want any flywheel to speak of, though four-strokes will need back-torque limiting clutches to prevent rear wheel chatter under braking resulting from the engine braking you get with a very light crank. It's almost the same for MX, because you steer the vehicle by breaking traction, and you ram it into a berm under g-loads to accelerate. But for dirt track, where you need to balance the amount of wheel spin you're getting very precisely to steer, you don't want an engine that instantly zooms up when traction goes away -- so you trade-off a theoretical acceleration advantage that lighter flywheels might give for some controllability that actually gets you around the race track quicker. Similarly, streetbikes are easier to ride with a little bit of flywheel smoothing out the driveline, but sportbike riders have been trained to expect quick revving engines by the Japanese. Take someone off a 600 and put them on an XB12, it's initially going to feel strange and slow-revving to them -- which has a lot to do with the commentary of the English journalists. | ||
| Reepicheep |
Elvis,
I think this is the root of the confusion (well, one of the confusions, Aaron and Steve are discussing a different tangent). If they are at the same load conditions, they are at exactly the same power. Power == load. I think that what you are saying is that, at steady state, if two engines are producing equal torque, but one is producing more power, that one is spinning faster. Which is exactly correct (obviously). But don't confuse torque (a theoretical non moving force measured at a fixed distance on a virtual lever arm attached to the crank) with power (force being moved *through* a distance over time accomplishing real world measurable work). I could trivially produce an engine that costs $50, weighs 20 pounds and develops 1000 foot pounds of torque. It would generate virtually no power however. The Aaron / Steve discussion is the effect of transient energy stores on transient activities, not a steady state power analysis. | ||
| Gonen60 |
So would it be fair to say, the XB9 has some advantages over the XB12...And the XB12 has some advantages over the XB9. The XB12 has More HP and torque, But Because of the XB9s higher reving engine and Gearing, it in away compensates for the 12s power advantage? | ||
| Darthane |
How about this for compensating? You have a 9 and are happy with it, so screw the 12s. | ||
| Glitch |
Yeah what Darthane said if you have an S and happy with it screw the Rs! just kidding Why would someone that would buy a GSXR, buy a 600 instead of a 750? Why would Suzuki build a 750 if the 600 would spank it?  | ||
| Bud |
quote But I know something from a little birdie....yes on a dragstrip the 12 is faster than the nine. By how much I am not aloud to speak raising the bet, $50 on the 12 to win  gr,m | ||
| Gonen60 |
Darthanne, got nothing to do with Me being Happy with My current Bike. I am just trying to find out how the 9s and 12s stack up against each other. I think this has been a great thread. One of the best I have seen... | ||
| Aaron |
Elvis, do this. Put the XB9 primary on an XB12 (or vice-versa). Run them down the road side by side, same gear, same speed, same rpm, same rider weight. Whack the throttles open and watch what happens. | ||
| Dynarider |
The XB12 will kick the 9's ass. End of story. | ||
| Mookie |
darth, I guess I should have gotten the 12. the reason being is that while everyone sits around the campfire and talks about how fast they think it is... we could have gone and found out for ourselves... er. uh.. anyways. | ||
| Cyclonecharlie |
Hey,lets keep it fair.How about a XB9R with the 1200 kit (short stroke with same displacement) to line up against the XB12. Wheres your money now?......Later Charlie | ||
| Bads1 |
But then a stage three kit to the heads some cams,a Force pipe and cylinder's and piston's my money would be where ever you wanted it to be.Now there sound's like a beast of a 12. | ||
| Buelliedan |
Charlie posed the question I want to know. A 9 stroked to 1200 vs a off the floor 12. Which would have more power?? | ||
| Gonen60 |
The XB12 will kick the 9's ass. End of story. I think you would be surprised | ||
| Prof_stack |
Surprised? Not at all. My test-ride of the XB12S left me VERY impressed by the surge of acceleration from the low 2,000's on up. Yes, in a straight line the 12's will "shut down" the 9's. Prof xb9s | ||
| Dynarider |
Gonen60, dont be so disappointed that you bought a 9 when you coulda waited & had a 12. Sour grapes do not taste very good. The 12 is a beast compared to the 9. Nothing wrong with loving your bike, but be realistic about it at least. | ||
| Gonen60 |
Not sour at all, and not concerned with drag racing ETs (The 12 would win, not by much)...If I wanted a 12 I would go out and buy one tomorrow. I look forward to running against one when the time presents itself. I don't know why this has turned into ME being mad, or sour or upset, I am not in the least bit. If I was worried about having the fastest bike, I would have bought another Suzuki GSX-R 1000, or a Honda 600RR, KAW 636, Yam R1, etc.... I like being the underdog, I let my riding ability speak for itself... Just thought the whole idea of XB9 vs XB12 is thought provoking..I think other here also think so. A lot of great points of view on this thread..I thought this was what the board was about. If it's to heavy or tiresome for some, go start a thread about Buell T shirts or something else mundane | ||
| Darthane |
darth, I guess I should have gotten the 12. the reason being is that while everyone sits around the campfire and talks about how fast they think it is... we could have gone and found out for ourselves... <~~Mookie Blah. I love my 9R, hands down. I bought it before there was even a 9S, let alone a XB12, and not one regret. Even if I had the money I wouldn't buy a 12 now - it's the same bike, just a bit more powerful. I want something different, not more of the same! | ||
| Court |
Go ride your 9's and enjoy...they are fabulous motorcycles. You know...I almost balked on the 1991 and caved into the rumor that Buell would introduce the single rotor, new forks and loose the A.C.T. system for 1991. Looking back.....I've never looked back. Court | ||
| Glitch |
If it's to heavy or tiresome for some, go start a thread about Buell T shirts or something else mundane          | ||
| Misato |
well, the nallin/force kit I put on my 9 REALLY brought it to life. I cant wait to get stageIII heads.. I'd be more than happy to run any 12's around seattle  | ||
| Dynarider |
Saw an XB12 rider wearing one of these as he was smoking a 9 You did ask for a t-shirt topic right? | ||
| Misato |
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| Prof_stack |
Misato, get your stinkin' 9-now-12 and meet me at Interlaken boulevard in Seattle. We'll see who can handle their Buells. Oh yeah, I'm 168 lbs. ![:]](http://www.badweatherbikers.com/buell/clipart/proud.gif) Seriously, I love my 9s and have no desire to trade up. Its paid for, too... |
