Originally posted by: JensUK
Overcoming inertia via smaller engine parts and less mass has little to do with the acceleration and traction.

Don't think just because you can use the terms inertia and "F=ma" that it makes you sound any more intelligent.

In drag racing, if your car is to light and your turning to much hp and torque, you will literally sit still while your tires are turning at 9,000 revolutions per second without going anywhere.

This is a big problem even in sport bikes racing.

Could you imagine a 160hp ATV set-up running against a gsxr 1000?

Originally posted by: cctman
Overcoming inertia via smaller engine parts and less mass has little to do with the acceleration and traction. Another words it makes vary little difference when dealing with over all performance. The big factors are contact surface, and hp/torque curves. Don't think just because you can use the terms inertia and "F=ma" that it makes you sound any more intelligent.

Originally posted by: Corpsie
This is great, you say that less mass has little to do with acceleration, then you requote that F=ma

ha ha.

Originally posted by: cctman
Anybody can build a super hp motor. What difference does it make if you can't use it. Again, have you ever seen a 60-80hp pro MX bike? Nope! Have you ever seen a 60-80hp MX ATV? yep! I have one in my garage.

Another point I would like to make...you said "Weight is never counter productive to traction unless you are on a material in which you need to "sink down". "

Although vary vague and I'm not sure what your trying to say here, I have been in the race industry for many years, and there are many factors in racing, but if your trying to say that to little weight can not be counter productive in regards to traction your vary wrong. In drag racing, if your car is to light and your turning to much hp and torque, you will literally sit still while your tires are turning at 9,000 revolutions per second without going anywhere.

This is a big problem even in sport bikes racing. You ever here of counter stearing? This is a fairly new technique involved where your laying into a curve you literally twist the throttle and spin up the back tire until it heats up and spins up and catches traction and you literally get slinged out of a corner. IT used to be pretty uncommon but now almost every AMA SBK racer uses the technique, at least in the full liter bike class.

Now, to much weight obviously can create traction problems too, but so can to little weight.

Thats why I stick to my guns and think other than changing composite materials and tweaking suspenions there is very little to do with dirtbikes, and I don't see any major changes in the near future that are going to completely revolutionize the dirtbike industry. Its pretty much peaked out.

Now ATV's on the other hand, we are light years behind technology and what we can do. Just wait until an ATV version of the sport bike is allowed on the streets. Could you imagine a 160hp ATV set-up running against a gsxr 1000? I'm sure its only a matter of time. The dirtbike days are pretty much numbered.

And don't get me started on ATV's out braking MX bikes because of there larger contact surface...

Originally posted by: cctman

I think you and JensUK need a lesson on how not to pull information out of context and redefine the sentance structure around the words in order to alter the orginal meaning. What I said was .. "Overcoming inertia via smaller engine parts and less mass has little to do with the acceleration and traction. Another words it makes vary little difference when dealing with over all performance." I didn't say that in the realm of science and physics it has little to do with the Netwon's laws, what was meant was the overall "acceleration and traction" of the ATV and I qualified this by saying "Another words it makes vary little difference when dealing with over all performance."" And this is true, of all the variables that influence performance, bringing up inertia into the equation which is the initial force involved in moving an object has little to do with the over all performance. hp/torque and contact patch have alot more to do with overall performance than inertia and saving weight in the engine.

Originally posted by: Corpsie
Lowering mass lowers a body's intertia! F=ma. It's really simple.

Smaller engine parts reduces the mass moment of intertia which allows the engine to produce more torque at the output shaft. Torque = mass moment of intertia * angular acceleration.

You can use an engine that produces less torque in a lighter weight vehicle, because it is a lighter weight vehicle.

Mass have a LOT to do with performance.

Originally posted by: DEMag
Ever heard of the CR500 or KX500? Modded, each will EASILY produce better then 60 HP. My modded YZ250 got over 50HP.

Do you see quad races selling out 60,000 seat stadiums? Nope. Maybe I'm not looking close enough, but I haven't seen a single quad race on tv. I don't see any pro quad racers doing TV commericals, do you? Event money (supercross, moto-x, x-games, gravity games, etc), sponsorship money, tv coverage, and rider salaries have never been this high. Ever! And they keep going up. If quads are so much better then bikes, how come they are not dominating the industry? Funny thing is, they sell more quads then dirtbikes. Yet the bikes are still more popular. Maybe with the "intelligence" you gathered from your years in the racing industry you can fabricate some scientific BS reason for that.

No doubt ATVs have come a long way and are progressing even further every day. But to say bikes are going to be phased out and "their days are pretty much numbered" is beyond ignorant. And how many bikes have you seen banned lately? None! How many quads have been banned recently? Hmmmm, the Banshee comes to mind. Phased out by 2006 IIRC.

Originally posted by: cctman
Demag, if your asking the question, then the answer lies in the obvious fact that ATV's haven't been in the lime light of the media and TV over the last decade. I would blame that largely on not that motorcycles are suppose to be more exciting (which is rediculous), but the fact that law suits, and the demise of the 2 stroke ATV's, and manufacture expensive driven choices have placed dirt bikes in front center. Lets not forget that the success of the dirtbikes has been largely linked to the fact that they have been protected largely under the umbrella of the AMA, if not for the AMA support and collateral big brother super bike support, the dirt bikes and MX/SX wouldn't be half as successful as they are today.

Originally posted by: cctman

You can have a smaller displacment engine with heavier internal parts and it will perform just fine if the output charteristics are well off. ex; if this weren't true then how come pro level drag cars still use big block engines with traditional pistons and cams. Sure you can lighten them up, but take away the larger tires and see where that gets you. The same can be said off ATV's. This will always be the benefit of an ATV over the dirtbike.