I think everyone kind of has the right idea. The honda doesn't start making it's power until about 8,000 rpm. (My S1000RR feels asleep until 6000) You have to be riding like you stole it, and it takes more than the 2 seconds that the race lasted to get up to those revs. The honda rider seemed rather timid / inexperienced, and hildo really seemed to know his stuff. Also, those big v-twins make loads of power off the line.

I'm not sure how much credence I can give the wiki page...I note it claims things that are obviously wrong, like "the design does not have a long lifespan when compared to other engine designs due to large numbers of moving parts" while in fact this motor has far fewer moving parts than normal motors. It did make some good points, like the first one that occurred to me about friction, but also made some bad points such as claiming 'mechanical complexity' as a drawback, while in fact it seems far more simple than normal motors.
"extra complicated machined parts" also exist in normal motors, and can be made fairly cheaply and easily in bulk.
Excess use of oil is an issue, but one they should be able to solve with proper machining and materials. Low RPM is fine for many applications, like a generator, so long as it's efficient it's fine and might even be better. Since you get high torque at low RPM with this design, low RPM seems to be ideal.
They claimed it had comparable horsepower to the same displacement normal motors in the prototype...if true, that point is moot.
Actually, there seems to be less moving mass in this motor, consider the mass of the crank shaft and counterbalances, connecting rods and pistons, the camshaft, rods, lifters, rockers, and valves. This motor only had a compact 'crank' and the connecting rods and pistons, and the output shaft. That's less actually moving to my eye.
The 'potential for explosion' was claimed on Wiki to be a design flaw of the case thickness around the 'crank', which could easily be thickened if it doesn't have to fit inside a torpedo....potential removed.
I'm not saying it's perfect, or necessarily even feasible, but it does seem to have more going for it than you give it credit for and is worth following it's progress to me.

http://en.wikipedia.org/wiki/Revolving_cylinder_engine

Read the last few paragraphs to see that this is basically another "Solar Roadways" situation. E.g. too much hype, not enough practical purpose.

Let's breakdown the problems here: extra complicated machined parts, excess usage of oil (to lube everything up), low rpm and horsepower due to the amount of material needed to move (sure a standard engine might weigh more, but less of it actually moves), additional wear over time, and the potential for explosion with extended use.

Basically, these things are only used in torpedoes, where a massive explosion is the whole point.

As far as wood lathes go Mordhaus, this one shown here is one you'd find in an enthusiast's home shop or a light industrial shop-Had one in 8th grade wood shop that was a bit more formidable that this one that you could have mounted a larger round of wood upon with a much larger electric motor with way higher RPM's.
Love to try a couple of solid wood or other spheres for some speaker enclosures-Always coveting an industrial lathe.

Check this one for scale:
http://www.woodfast.com.au/index.php?p=1_5

I had this on 45 rpm as a kid and played it on a plastic turntable.

Or a certain amount of time where they constantly go from say 2k-4k rpm gradually up and down without any of them touching.

Don't feel bad, if you listen you'll hear the crash car's RPMs go up. Sounds like he wanted to hit the brakes on this guy but missed the right pedal.

He went through the entire vid without mentioning Williams Hybrid Power, the spin-off from the flywheel storage developed for the Williams F1 car in 2008/2009:



Unfortunately it couldn't be scaled up to the increased KERS output required for the 2011 season, at least not in a way that fit in an F1 car, so Williams now run the same electric KERS as everybody else. The flywheels are used in other racing series and in road cars though, as mentioned in their vid.

One very obvious difference between the prototype bicycle system in this vid and the WHP version is that they are using relatively lightweight composite flywheels and then spinning them to speeds that would tear apart the car flywheel from this vid, typically 20,000 to 50,000 rpm. This greatly increases the amount of energy storage available which increases linearly with mass, but with the square of rotational velocity.

http://rpm2.8k.com/basics.htm

For a bicycle, the gyroscopic effect would actually help maintain balance. The added weight isn't a big deal if the place you ride is mostly flat. There are some safety concerns of any appendages contacting the flywheel.

Even with awesome bearings, that flywheel probably loses most of its stored energy overnight. ("serious" energy storage flywheels are floating magnetically in a vacuum at 50,000 rpm)

For cars, batteries can store *many* more joules of energy per kg, so using flywheels instead of batteries would make the vehicle less efficient- since it's heavier.

Would be neat to make a pedal-car with flywheels, rider(s) would pedal constantly to add energy to the flywheels, even when at a red-light. Sell it as exercise equipment for short commutes.

Out of curiosity, how does a 15-pound high-rpm gyroscope affect turning on a bike?

Ok ant, that was a joke! So, I am gonna up vote this viddy on-accounta I learned a new word (HOON- gotta love it as an onomatopoeia) and I have never seen a POV viddy of a car being driven into a pond before, not-counting Hollywood renditions...

My own hoon stories could fill a small journal. One of my favs was the assassination of a Datsun B-210 with RPM, then shotguns-The poor car lurched struggling to a stop, belching oil and smoke as we double-tapped the engine block with slugs Fun-time, victimless country hooliganism-

My understanding is that a correct autorotation is NOT accompanied by a hard landing. However, it IS very difficult to pull off (hard---what a pun!), the closest personally analogy I can think of, being docking a boat by chopping the throttle while still tens of yards away from the dock, casting it up alongside just So---with all the kinetic energy elegantly spent before kissing the dock side.

The helicopter analogy, again, to my knowledge, is that once engine failure is clearly happening, you flatten the pitch, give up the lift the blades were generating, start falling and preserve main rotor RPM as much as possible---and you get exactly one chance and one chance only to pull pitch (make the rotor blades bite the air) at just the right distance above the ground to decelerate the helicopter just as all the rotational energy of the blades finishes spending itself in generating that last, final iota of lift--and then you kiss the ground.
Or not.

YouTube description:

According to the pilot-in-command (PIC), he was performing autorotations at the lower part of the main rotor rpm green arc in part due to weight considerations. Upon entering the accident autorotation, he maintained an airspeed between 85-90 knots in the hope that extra speed would allow a more aggressive deceleration flare prior to touchdown, which should in turn further slow the rate of descent and forward speed. The helicopter's rate of descent was high, and as the PIC turned the helicopter onto the runway heading it was apparent to him that the rate of descent was excessive and that he was too low to execute either a proper deceleration flare or perform a power recovery. He attempted to level the helicopter as much as possible prior to impact to minimize the damage to the helicopter and prevent injury. The helicopter landed hard with the left skid contacting the runway first. The left skid collapsed, damaging the outboard landing gear damper attachment structure. The helicopter slid about 100 yards before coming to a stop. According to the manufacturer, the main rotor rpm range is 90 percent to 106.4 percent. At the helicopter's weight and the density altitude on the day of the accident, the main rotor rpm during the autorotation should have been above the 106.4 percent limit (red line), requiring the pilot to increase collective pitch to maintain the rotor rpm within limits. Performing autorotations at the lower part of the green arc provides less availability of rotor energy to perform an autorotation landing. The pilot should have recognized that he was not achieving the required main rotor rpm for the autorotations and terminated the maneuvers. The helicopter was within weight and balance limits.

The National Transportation Safety Board determines the probable cause(s) of this accident as follows:

The pilot's failure to maintain adequate main rotor rpm during an autorotation, which resulted in a hard landing.

Yes, exactly. It seems strange that they were seeing failures from springs at such low engine rpm's, but in any case I have heard that you just can't achieve more than 18,000rpm with springs no matter what.

I have found a web page with some nice diagrams and explanations of the electro hydraulic system used by Renault... they have indeed done away with the cam entirely (at least in testing, not sure if it has raced since that article was published). Since the engine management system would have to manage this, and it is a control unit supplied by McLaren, we can be fairly sure that all the engine manufacturers have a common system.

http://scarbsf1.com/valves.html

"For the first 3,500 miles keep it under 7,000 RPM" - well there goes that warranty