function of the flywheel weight

[tschisi]

Hi!

Although it isn?t recommended for the 250 with stock exhaust i?m thinking about a selfmade flywheel weight.
It seems the StealthyOffroad weights are just an extended nut with a disc on the outer end.
Could simply be tightened with two oilfilter wrenches.
But: What does the weight prevent from tearing loose when stalling the engine at high revs?
Would you make the weight of alloy so it doesn?t affect the magnets?

thx

[Hillclimb#42]

The weights do turn on the threads, but also have allen set-screws around the perimeter to keep it from turning. I think their main pupose is prevent stalling in rough conditions. It would also slow the rev down, which can make it less snappy and therefore easier to ride.

[ThrottleJunky]

A post on this site has a brass ring shrunk onto the O.D. of the flywheel.   Pretty crafty and easy to do.
Maybe Friar Tuck or someone that can jockey around this site better than me pull that thread up for us?? 

[DoldGuy]

A post on this site has a brass ring shrunk onto the O.D. of the flywheel.   Pretty crafty and easy to do.
Maybe Friar Tuck or someone that can jockey around this site better than me pull that thread up for us?? 

http://www.kxriders.com/forums/index.php/topic,4918.0.html

Reply 25 shows a good picture

DoldGuy

[Friar-Tuck]

 
 Thanks Gold Guy!  I was just gonna' start searching... I have been trying to gather up a bunch of posts and put together a folder for myself so if /when someone needed something I could find it.  Now I have a bunch of info that is need of a catalog system of some sort... and I'm still not through all the 500 posts...and every time I start going through them I find more nuggets I missed the first time....
   The only flywheel weights I remember seeing Somewhat unconventional were the thread in the 500 engine mod with the Mitch Payton cylinder that Don Found from the Jeff Ward Bike.

  I'm sure Danger would love to hear any suggestions on improving the site.  I am really just a member who has random blocks of time to search the web account I have so little money to actually DO anything, and with my skeleton melting with arthritis It's harder and harder to even get up in the morning  

 Now back to your question!  Here's an artical copied from MXA :
http://www.thumperfaq.com/mxa_flywheel.htm


And one from A great auto rescource:
http://victorylibrary.com/tech/inertia-c.htm


  Tuck\o/

   This member explains his steahly on a 250:
http://www.kxriders.com/forums/index.php/topic,3154.0.html


 And a tidbit from the Books of BDI :

"Another option is to change your aluminum clutch plates out for steel ones. I'm Just assuming your bike has aluminum clutch plates. If they are you can add 65% more weight over the aluminum plates."

And Danger :

"I have a flywheel weight and my experience is no power loss.  The extra weight on the flywheel stops the rpm from spinning up so fast.  There is a point at low rpm, so low the weight of the stock flywheel can't push the piston over top dead center because of the gasoline combustion.
   You know, killing the engine and it jerks to a stop and almost puts you over the bars?  With the extra mass of a flywheel weight the flywheel can push past top dead center at lower rpm's." 

[Motorrad]

If anyone needs measurments off my flywheel weight. Let me know.
-Dave

[The Flyin Hawaiian]

Hi!

Although it isn?t recommended for the 250 with stock exhaust i?m thinking about a selfmade flywheel weight.
It seems the StealthyOffroad weights are just an extended nut with a disc on the outer end.
Could simply be tightened with two oilfilter wrenches.
But: What does the weight prevent from tearing loose when stalling the engine at high revs?
Would you make the weight of alloy so it doesn?t affect the magnets?

thx

Im running a 11oz Steahly on my 04 KX250 with stock exhaust. Not sure where you would have heard that from. It runs fine, no ill effects. It hasnt loosened up in 4 years, although I have had it off and on many times. I switch to a 9oz when the races are in more sandier, wide open conditions. The 04 KX250 already has steel clutch plates.

[tschisi]

Motorrad, how heavy is your weight?
Is it selfmade? Made of what?
How does it connect, i see no screws?

[Danger4u2]

The Steahly flywheel weights have crimped holes the set screws are in.  The outside edge of the hole is crimped so the set screw won't vibrate out if it becomes loose.  If you ever need to remove the set screws completely, after removing the weight you screw the set screws toward the center of the weight.

[snoopjonnyjon]

My 500 has stock flywheel, but I have ridden a YZ250 with stock, and heavy flywheel. The heavy flywheel definately allowed for a lower idle speed, and smoother running at low rpm. I would think for all but the most aggressive rider, the flywheel weight pros outweigh the cons.

[coalpilot]

I would think for all but the most aggressive rider, the flywheel weight pros outweigh the cons.

I agree.

[RICHK]

I also here that they suck some of the vibrations out of the 500's