"There are known knowns. These are things we know that we know. There are known unknowns. That is to say, there are things that we know we don't know. But there are also unknown unknowns. There are things we don't know we don't know."

 

Brian, i know you know your stuff but come on, that is my point.
In theory perpetual motion exists.

You can't move mass without loss.
If you do no more than increase the mass, you will increase the loss.

 

Friction is unchanged whether the flywheel is heavy or light. So that a red herring in this argument. How is frictional loss greater for one case over the other? Unless you changed the bearings, too.

 

I think that was me that said that, not Finger, but I think he would agree on the point of the flywheel.

 

Ha, this is crazyness.. Even iffff the flywheel somehow did free up horsepower.. it would be so absolutely minimal that it wouldnt be noticed in the slightest..
Like said a bunch of times.. It creates momentum, stores energy, smooths out the power. IMO this HP debate is blown out of proportion.. haha
maby more discussion about characteristics the flywheel creates for the bike on different terrain's.
Why is a light flywheel seem to be better in sand? Is it better for a 1/4 mile kind of racing?
Heavy flywheel good for trail riding? Do trials bikes have heavier or lighter flywheels?

 

Not true.
Heavier flywheel means more load on the bearings.

Brian, you don't really believe that increasing the weight of a bike doesn't effect top speed do you?
"Simple theory" says it shouldn't, but it does.

 

[quote=green242;337110]Ha, this is crazyness.. Even iffff the flywheel somehow did free up horsepower.. it would be so absolutely minimal that it wouldnt be noticed in the slightest..
Like said a bunch of times.. It creates momentum, stores energy, smooths out the power. IMO this HP debate is blown out of proportion.. haha
maby more discussion about characteristics the flywheel creates for the bike on different terrain's.
Why is a light flywheel seem to be better in sand? Is it better for a 1/4 mile kind of racing?
Heavy flywheel good for trail riding? Do trials bikes have heavier or lighter flywheels?[/quote


Agreed, we are getting a bit carried away here.
The increase, if any, will be minimal.

But heh!
It's better than debating mufflers or sprokets?

 

LOL You guys got jobs right. funny stuff

Yup I would agree.

For fun.....you never addressed the dyno results for the heavy tire vs light tire and different hp results. Now assuming the dyno is 100% accurate and reproduce-able....lol.

Why did the dyno report a lower hp for the heavier tire. Well the funny part is that hp or power measures force times distance divided by time not time squared (acceleration) ..... BUT assumes a steady state...ie constant rpm. Now we all know that dyno's measure hp under acceleration....even thou the computer makes a calculation every half a second or less for example...but there is a time interval involved while under acceleration thus the discrepency (sp).

But the really funny part is that we are talking about 10oz or so on a flywheel....how much energy does it take to spin up 10oz to 9k rpms....not much to say the least, but that little bit of inertia really can effect the characteristics of the motor.

Overall my original opine was correct that a dyno would read a lower hp with a heavier tire or flywheel....because of the time interval the dyno takes to make the calculation while the motor is accelerating, if it was steady state the hp would be the same or if the dyno could get the time interval infinitely small during the measurement, then hp should not change, according to math. But that is not reality.

I just caught two beer phish, so I hope that post made sense.

Btw for my riding, any increase in acceleration rate is good, inertia is not a concern 90% of the time because I am wot. lol

My buddies ktm 300xc-w really needs the flywheel weight he put on, even for our riding....it still stalls easier than a stocker klx.

 

On the flywheel vs HP debate:

http://thumperfaq.com/mxa_flywheel.htm

See "QUESTION SEVEN". This is what I've been saying. I said changing the flywheel weight will change the character of the power delivery. See? I'm not nuts. Ok, well maybe I am, but that doesn't mean I'm wrong about this.

 

I don't need to check the link, flywheel weights dramatically effect the performance of a bike.....we both agree on that.....shoot I got the Steahly Off Road Catalog in front of me right now..... one of my buddies is a Physics major and needs help picking and installing a flywheel weight for his new smoker....