Biker jailed for 157mph ride in U.K.

Re: Bikers responsible for anti-moto laws.

"When will the motorcycle industry realize that the future depends on the public's perception of us???"

They realize that now, and the public's perception of us is the highest it's ever been. I solated incidents like this will not change that.

"Why is it that the only time we see motorcycles in the news is when IDIOTS do stupid things on them?"

Because it's the NEWS- when was the last time you saw a positive news report about anything?

"When will the manufacturers realize that they are putting themselves out of business by catering to the Ultra Fast latest greatest crowd? "

Will Never Happen- this same argument has been used for the last 20 years for both motorcycles and high-performance cars and it keeps not happening.

"They keep making fewer bikes for entry level riders and more bikes for experienced riders."

Wrong. Look at the number of entry-level cruisers, dirtbikes, standards, naked sportbikes, etc. available today. This number has seen huge increases recently. The only thing that has changed has been the performance levels of pure sportbikes.

"Have you ever noticed all the high-performance bikes for sale by owner with less than 3000 miles on them?"

Yes, and it's usually because they grow tired of them and move on to cruisers or sport touring bikes. Talk to some of these people and they will tell you this.

Re: Bikers responsible for anti-moto laws.

Uh Captain, sir, I looked up the websites and there are indeed very few entry level road bikes. Honda has the 250 Nighthawk and Rebel. Buell has the Blast. Yamaha has the 250 Virago. Suzuki dropped the GS500 (which is pushing the envelope for a beginner bike). The 70HP SV650 is hardly a beginners bike.

I guess the question is "What qualifies as an entry level bike?" Probably a bike under 30 HP is what would be considered a traditional entry level bike. Like the old CB350. Enough power to drone on the freeway, enough power so you can avoid being run over, but not enough power to get you into serious trouble at the flick of the wrist.

There simply aren't many of those types of bikes. Dual Purposes are a consideration, but with the extremely high seating positions on most of them they are hardly friendly to a new user either, or a 5'6" 16 year old.

I guess these days "entry level" is an 883 or a Shadow 750. However these are capable of 100mph and hardly classify as a beginner's bike one would want to put a 16 year old on. A friend of mine recently went out of state to pick up an old 450 Nighthawk for his 16 year old. Still this is a bit of a lot for a neophyte.

There are loads of neat 300-400cc bikes outside of the US, but the manufacturers have given up trying to sell them here. I don't blame them. All I see around here are squidlies and big cruisers. I guess the macho image trumps all.

Gen(whatever) Extreme lines up to attempt suicide on CBRYZKZGSRRRRRRs one after the other, T-shirts and sandals flapping.

Mr Physics just called me

And he wants me to introduce all of you to the difference between momentum and kinetic energy. As any high school physics text will tell you, momentum is mass * velocity ("mv"), and kinetic energy is one-half mass * velocity squared ("1/2mv^2").

Wakked1's "35%" figure is roughly accurate with respect to momentum, not kinetic energy; and while momentum is not irrelevant, if we're talking about which one you'd rather get broadsided by driving home from work tonite, kinetic energy is what we're really looking for.

Having said that, both Mr Physics and I are stunned to report that the relative order of Wakked1's examples hold true with respect to kinetic energy as well.

We calculated the kinetic energy of Wakked1's 750lb bike to be 8,437,500 (don't ask for units, the relative comparison is what really matters) and the KE of the 4500lb SUV to be 11,025,000.

All three of us (Mr P, my high school physics text, and myself) are flat out amazed that despite the relative significance of these variables (the speed is *SQUARED* for cryin' out loud!), even when traveling less than half as fast, the SUV packs a greater wallop than the bike.

Sure is gonna make me give the SUVs a little wider berth driving home tonite.

I'll save the textbook stuff for the professors, but I was thinking momentum as that is generally conserved in a collision, and then your body has to deal with the energy introduced by the corresponding and rather abrupt change in velocity.



i.e. energy is the problem for the vehicle/body to absorb (esp when hitting a stationary/immovable object), but momentum is how you figure out the effect of a collision with another vehicle upon your own... hence the fast bike vs slow SUV discrepency.. you will slow down lots, SUV will slow down relatively less (hence 35% vs 77% relative ratios).



The delta in velocity is key as that is what your body has to absorb in the form of your_mass/2*your_speed^2. So the speed you should be looking in your energy equation is not the velocity of a given vehicle, but the relatively change in velocity upon its occupants caused by change in momentum.



You're right that I shoulda said momentum vs energy, didn't think there were any physicists lurking nearby.



Hopefully I've confused the issue further.