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Flywheel Weights
Posted: December 4th, 2008, 9:12 am
by CR500PHIL
I just discovered the engine I bought has a Stealthy flywheel weight on it and I am debating whether or not to remove it. My question is what does it do to the power delivery? Does it kill the hit of the engine? I like extreme hit for roasting on beaches etc. Does it shorten the life of main bearings? Finally how are these removed - it looks like it is screwed onto the flywheel shaft but not sure.
Re: Flywheel Weights
Posted: December 4th, 2008, 9:48 am
by MICK
CR500PHIL wrote:My question is what does it do to the power delivery?
Softens the onset of power, reduces throttle response and stalling...
CR500PHIL wrote:Does it kill the hit of the engine?
Yes...
CR500PHIL wrote:Does it shorten the life of main bearings?
No...
CR500PHIL wrote:Finally how are these removed
If I remember right it uses the reverse threads of the flywheel. There's dozens of methods of locking the engine in place. Pick one and turn the weight clockwise to loosen it. I believe Steahly's came with a device that threads into both sides of the weight for this. You could easily fashion your own if you don't have this tool.
Posted: December 4th, 2008, 9:51 am
by redrocket190
The power delivery is changed, but not the power. Depending on the weight the power will build more smoothly and you will get less "hit". Steahly makes recommendations based on rider ability and type of riding. I just got a 13-oz weight for my bike (because I am a squid that apparently has a magnetic attraction for fences), but MXA recommends 9-oz for motocross applications. The weight screws onto the end of the crankshaft on top of the existing rotor. They provide a bolt-on tool that provides a 1/2" square hole for your torque wrench. You take off the tool after the weight is tight with the stock rotor. Some allen screws then bear down on the edge of the rotor too. You use the existing nut (but not the washer) to lock it all down. FWIW it's worth I think Bob wieighted the Electrosport rotor from Service Honda at 16 oz....
Flywheel Weights
Posted: December 4th, 2008, 10:01 am
by CR500PHIL
It sounds like people who ride flywheel weights should be riding XR 200s instead of CR 500s.

Re: Flywheel Weights
Posted: December 4th, 2008, 11:04 am
by redrocket190
CR500PHIL wrote:It sounds like people who ride flywheel weights should be riding XR 200s instead of CR 500s.

Ouch! And I was about to offer you the removal tool....
Posted: December 4th, 2008, 11:05 am
by britincali
I want to try one on my AF.....
Re: Flywheel Weights
Posted: December 4th, 2008, 11:08 am
by CR500PHIL
redrocket190 wrote:CR500PHIL wrote:It sounds like people who ride flywheel weights should be riding XR 200s instead of CR 500s.

Ouch! And I was about to offer you the removal tool....
Just a joke - actually if so many people run them perhaps I should try before I remove it - I may find it great. Plus removing it does not involve much besides removing the ignition cover anyway. I love the wow factor of power but may find the usability even more enjoyable.
Re: Flywheel Weights
Posted: December 4th, 2008, 11:18 am
by eyesky2002
CR500PHIL wrote:It sounds like people who ride flywheel weights should be riding XR 200s instead of CR 500s.

The 13oz took nothing from my bike power wise, 2nd gear full bore starts and it pulls the front wheel up in every gear, but makes it much more usable in other spots... Before I would break lose and start to spin out under half power in turns and burms, now it seems to track better and I can really dump the gas into the jug!! And yes in the lazy sense you can lug it into corners and do less clutch work, trails are no longer the work out they were!
I like what it did to my bike and I ride hard, but maybe I am an electric fence biting squid too
Just my 2 cents

Re: Flywheel Weights
Posted: December 4th, 2008, 11:22 am
by CR500PHIL
eyesky2002 wrote:CR500PHIL wrote:It sounds like people who ride flywheel weights should be riding XR 200s instead of CR 500s.

The 13oz took nothing from my bike power wise, 2nd gear full bore starts and it pulls the front wheel up in every gear, but makes it much more usable in other spots... Before I would break lose and start to spin out under half power in turns and burms, now it seems to track better and I can really dump the gas into the jug!! And yes in the lazy sense you can lug it into corners and do less clutch work, trails are no longer the work out they were!
I like what it did to my bike and I ride hard, but maybe I am an electric fence biting squid too
Just my 2 cents

Well in a sense then if the bike is pulling rather than spinning you may actually "feel" the power more in some cases I guess.
Posted: December 4th, 2008, 1:56 pm
by AlisoBob
britincali wrote:I want to try one on my AF.....
30hp squeeze,
and a flywheel weight...

Posted: December 4th, 2008, 1:59 pm
by britincali
Posted: December 4th, 2008, 2:00 pm
by AlisoBob
Posted: December 4th, 2008, 3:58 pm
by MICK
redrocket190 wrote: FWIW it's worth I think Bob wieighted the Electrosport rotor from Service Honda at 16 oz....
It weighs 3oz more than the OEM unit. Stock is 20.4oz.
Personally I don't mind what a FWW does when you twist the throttle. What I hate about them is what they do when you let off...
http://au.youtube.com/watch?v=XKRGVPmOwd0
Posted: December 4th, 2008, 4:08 pm
by AlisoBob
MICK wrote:What I hate about them is what they do when you let off...
A seldom discussed fact.... good one Mick!
Posted: December 4th, 2008, 4:08 pm
by britincali
I never even considered that....
Posted: December 4th, 2008, 4:20 pm
by MICK
AlisoBob wrote:A seldom discussed fact....
And why not is beyond me? It's not like splitting hairs for crying out loud...I find that every bit a factor as the change in power delivery.
These are my thoughts why, and no disrespect intended towards anybody.
1. Riders don't compare their bike before and after like they should. Especially to get an idea just how much FWW they need. This is rediculous because testing different FWWs can be done simultaneously back to back within just minutes.
2. Riders who use FWWs just aren't very good. They couldn't obviously regulate throttle control much less notice when their bike handles differently.
I've used FWWs on every single bike of mine until now. I've raced the same bike with them and without. I've come to realize throttle control is a small price to pay for handling prowess.
Posted: December 4th, 2008, 4:33 pm
by JBaze
MICK wrote:redrocket190 wrote: FWIW it's worth I think Bob wieighted the Electrosport rotor from Service Honda at 16 oz....
It weighs 3oz more than the OEM unit. Stock is 20.4oz.
Personally I don't mind what a FWW does when you twist the throttle. What I hate about them is what they do when you let off...
http://au.youtube.com/watch?v=XKRGVPmOwd0
Not to sound dumb, but what do you mean? I have never used one so I have no idea what you mean. I have spent more time on single track bar banging trails than anywhere else and have always just ran 1 gear up and a Barrnet steel clutch and never had a problem, but I have been cosidering putting one of those flywheel weights on.
Flywheel Weights
Posted: December 5th, 2008, 5:32 am
by CR500PHIL
MICK wrote:AlisoBob wrote:A seldom discussed fact....
And why not is beyond me? It's not like splitting hairs for crying out loud...I find that every bit a factor as the change in power delivery.
These are my thoughts why, and no disrespect intended towards anybody.
1. Riders don't compare their bike before and after like they should. Especially to get an idea just how much FWW they need. This is rediculous because testing different FWWs can be done simultaneously back to back within just minutes.
2. Riders who use FWWs just aren't very good. They couldn't obviously regulate throttle control much less notice when their bike handles differently.
I've used FWWs on every single bike of mine until now. I've raced the same bike with them and without. I've come to realize throttle control is a small price to pay for handling prowess.
My first thought about weighting a flywheel was "why buy a bike with a lot of aburpt power and then deaden it when you could buy a bike with the type of power you wanted?". Of course I am new to FW weights but this thought always runs through my head when they are mentioned. I am building a CR 500 for the aburpt, sometimes uncontrollable power I receive from it. I admire this in my YZ 250 and think the CR 500 would be even crazier and hence more fun. I am going to try the weight none-the-less.
Posted: December 5th, 2008, 6:22 am
by AlisoBob
JBaze wrote:[
Not to sound dumb, but what do you mean?
2 strokes ( and CR500's especially) have minimal compression braking as is ..... try one with a pound of steel bolted to it....
You might not spin your tires leaving turn 4, but you may over shoot turn 5 as a result of no C/B.....
Posted: December 5th, 2008, 6:34 am
by JBaze
AlisoBob wrote:JBaze wrote:[
Not to sound dumb, but what do you mean?
2 strokes ( and CR500's especially) have minimal compression braking as is ..... try one with a pound of steel bolted to it....
You might not spin your tires leaving turn 4, but you may over shoot turn 5 as a result of no C/B.....
I see said the blind man. I do that already with it stock!
Posted: December 5th, 2008, 6:53 am
by Exnav
Kinda' like when people mount up some 44's under their newly lifted truck and then wonder why it doesn't stop so well with the stock brakes

Posted: December 5th, 2008, 7:33 am
by AlisoBob
Exnav wrote:Kinda' like when people mount up some 44's under their newly lifted truck and then wonder why it doesn't stop so well with the stock brakes

Same "flywheel" effect....

Posted: December 5th, 2008, 7:35 am
by Roostius_Maximus
its regular thread, back out the 4 small retaining screws from its perimiter, then thread bolts int he 2 large holes to grip the weight and turnit counter clockwise to remove.
FWW
Posted: December 5th, 2008, 7:39 am
by CR500PHIL
Roostius_Maximus wrote:its regular thread, back out the 4 small retaining screws from its perimiter, then thread bolts int he 2 large holes to grip the weight and turnit counter clockwise to remove.
Thanks - more and more I am think I would be happier without it but I am still a little torn. I like quick acceleration, quick braking and the rush of the hit so I am not sure if a FWW would be right for me. I work at a desk all week and on weekends want a machine to blow off steam on with that power rush.
Posted: December 5th, 2008, 9:56 am
by Roostius_Maximus
if you do have one try runnin it without.
I have one on the 91 bike, its really nice on a stock engine, stock swingarm in hillclimbing situations where she gets close to blowing out the wick.
I have a short rod 86 engine thats ported and makes alot of power in my 88 thats extended for climbing and it doesnt have a weight, but for the set up with extention its already unhooking the engine so the inertia doesnt matter and the engine will pickup rev no matter what.
I'm currently building a mild ported 91-01 style engine with a gnarly pipe, a welded moose weight weight on it and probably a 38 pwk to go in my 03 250 af project that will be my main trail, small hill, and general shit-ripper.