Holyman Posted January 31, 2004 Report Share Posted January 31, 2004 My motor doesn't start producing enough power to move it below 7000 RPM. Is that because of the flywheel or because of other factors? Quote Link to comment Share on other sites More sharing options...
Holyman Posted January 31, 2004 Report Share Posted January 31, 2004 While I'm thinking about it, I think one of the reasons the lock up clutch system seems to work so well for hill climbs especially is because of the added weight to the rotating mass. A lightened or even stock flywheel can only provide so much rotational duration. But if you added weight to the rotating mass, the engine would tend to maintain its speed under load. The clutch system has to weigh several ounces since it consists of machined marts and bolts w/ nuts as weights to actuate the clutch lockup theory. So if you add the benefits of less slippage in the clutch {debatable since the clutch tends to slip least when the vehicle is in motion especially at high speeds} to the added rotating mass of the clutch basket {which duplicates a heavier flywheel} you can almost explain why the lock out seems to work so well. I'd be interested to compare a lightened flywheel engine with a lockout equipped engine on a flat drag on several consecutive runs and see how things stack up. I think that the lightened flywheel engine would tend to win the race because it would rev quicker which would compensate for the minor amount of slippage in the clutch. Plus in a flat drag, the loads on both engines would be consistant. Quote Link to comment Share on other sites More sharing options...
909 Posted February 1, 2004 Report Share Posted February 1, 2004 My motor doesn't start producing enough power to move it below 7000 RPM. Is that because of the flywheel or because of other factors? other factors. Like I said, the thing runs just fine with the button flywheel, I just opted for lighting and a charging system. Quote Link to comment Share on other sites More sharing options...
boonman Posted February 2, 2004 Report Share Posted February 2, 2004 While I'm thinking about it, I think one of the reasons the lock up clutch system seems to work so well for hill climbs especially is because of the added weight to the rotating mass. A lightened or even stock flywheel can only provide so much rotational duration. But if you added weight to the rotating mass, the engine would tend to maintain its speed under load. The clutch system has to weigh several ounces since it consists of machined marts and bolts w/ nuts as weights to actuate the clutch lockup theory. So if you add the benefits of less slippage in the clutch {debatable since the clutch tends to slip least when the vehicle is in motion especially at high speeds} to the added rotating mass of the clutch basket {which duplicates a heavier flywheel} you can almost explain why the lock out seems to work so well. I'd be interested to compare a lightened flywheel engine with a lockout equipped engine on a flat drag on several consecutive runs and see how things stack up. I think that the lightened flywheel engine would tend to win the race because it would rev quicker which would compensate for the minor amount of slippage in the clutch. Plus in a flat drag, the loads on both engines would be consistant. Not at all Holyman. You see, a flywheel is attached to the crank. The clutch assembly is not. A lockup clutch works in hill climbs because it provides no slip, which can cost time on the clock. You see, once the bike is in the powerband, and screamin, (like at WOT on a hillclimb) the flywheel becomes much less of a factor. That would be like saying that larger, heavier tires will make more power up the hill because of the rotational mass. BUT, all that mass takes power to move. Example here, the 44" tires on my truck are retardedly heavier than stock, and oddly enough, MUCH larger. SO, with the rotational mass theory, this should help things roll along at speed, once moving. But, it doesn't. Completely opposite is true. It take alot more power to turn the tires efficiently. Thus, it takes more power to turn all this rotational mass. Like has been discussed, a balanced system is the best... I still think the lightened flywheel (when weight is taken form the outside of the wheel) is one of the best throttle response, and quicker rev building mods that one can do... Especially for the $$ involved.... Quote Link to comment Share on other sites More sharing options...
Ducman Posted February 3, 2004 Report Share Posted February 3, 2004 I think along the lines of boonman and 909. You could spend a ton of money on the theoretically perfect fly wheel shape and It would only make a tiny difference over a conventional flywheel in the bikes overall weight and in that once it is spun it might take less energy to keep it going due to not putting as much force on bearings and frictional components. This would only be because the bearings wouldn't have to be as beefy because the PRODUCT of enertia that the lighter hub could generate would potentialy be smaller even though the enertia is the same because nothing is absolutely perfectly balanced and spins perfectly true. At the same time the facor of safety goes down. The moving weights on the flywheel is a super Idea and would probably make a significant difference but there is no way that anyone would be able to develop one that wouldn't fly appart at 10K rpm much less a solid flywheel with a paper thin hub unless you had a multi billion dolar budget like NASSA and needed some exotic super light weight engine component where every gram of weight you shaved would save $10k on the cost to launch the object into obit or something. I think that the forces that the outer rim of the flywheel exert on the hub area just make it completely impractical. What might be more practical would be to somehow connect the flywheel to the crank with some sort of a slipper clutch mechanism so you could more or less turn the effects of the flywheel on or of. (Neglecting the whole stator and timing problem of course) But the problem is that when would you turn it on or off? Sometimes you need the flywheel to smooth out acceleration like when your wheels suddenly slip for a moment and then hook-up again. You dont want the engine to rev to the moon instantly every time the wheels slip in the slightest bit (negleting the flywheel effect of the tires and wheels and kenetic traction). Also when your downshifting you want the motor to resist spinning up too fast so you dont break stuff by accelerating the rods, crank, pistons faster then they can take it. The flywheel always acting on the motor makes it smoother and more consistant weither accelerating or decelerating. So, I say that there isn't any practical way to improve the flywheel other than (1) removing material from the rim; the conventional methods that exists, (2) buying a very expensive aftermarket flywheel that takes advantage of higher quality materials to distibute the weight to a more theoretically efficient shape, or (3) more or less removing the flywheel altogether; each of these steps getting more impractical from 1 to 3. After that unless your NASA, forget it! Quote Link to comment Share on other sites More sharing options...
909 Posted February 3, 2004 Report Share Posted February 3, 2004 hooray for ducman! Even if I was NASA, i'd invest the money in development of tiles and o-rings before looking into such a project. Quote Link to comment Share on other sites More sharing options...
Holyman Posted February 3, 2004 Report Share Posted February 3, 2004 Not at all Holyman. You see, a flywheel is attached to the crank. The clutch assembly is not. A lockup clutch works in hill climbs because it provides no slip, which can cost time on the clock. You see, once the bike is in the powerband, and screamin, (like at WOT on a hillclimb) the flywheel becomes much less of a factor. That would be like saying that larger, heavier tires will make more power up the hill because of the rotational mass. BUT, all that mass takes power to move. Example here, the 44" tires on my truck are retardedly heavier than stock, and oddly enough, MUCH larger. SO, with the rotational mass theory, this should help things roll along at speed, once moving. But, it doesn't. Completely opposite is true. It take alot more power to turn the tires efficiently. Thus, it takes more power to turn all this rotational mass. Like has been discussed, a balanced system is the best... I still think the lightened flywheel (when weight is taken form the outside of the wheel) is one of the best throttle response, and quicker rev building mods that one can do... Especially for the $$ involved.... The flywheel and the clutch basket always rotate at the same rate unless the clutch is disengaged. So the weighted clutch and the weighted flywheel would work the same. It's kind of like having one heavy whell and one light whell on the rear of your banshee. Second the flywheel helps maintain the smoothness of power delivery and duration of the delivery. The faster the flywheel rotates the longer it will run and the more it will resist negative draws on that power. So to use the tire analogy, the heavier tire WILL help keep your truck running in a straight line longer than a smaller tire provided the following is true... A- the weight is at the outermost part of the tire and B- the friction of the larger tire is equal to the friction of the smaller tire. It will take more power to get the tires to turn but once they are in motion, the will run longer. However more can be accomplished by having a heavier flywheel since the engine runs thru the trans and you have the advantage of the gearing to help you up the hill. I guess it does kinda come around to what you were saying... the smaller the flywheel the easier it is to turn and the quicker the revs but less duration. Quote Link to comment Share on other sites More sharing options...
Ducman Posted February 3, 2004 Report Share Posted February 3, 2004 Even if I was NASA, i'd invest the money in development of tiles and o-rings before looking into such a project. Yeah, the cheapist part is usually the weakest link. Those "O" rings cost whole lot more when it gets cold out and they bust ur damb space ship, and the "good stuff" might work wonders for sealing that gap around the window frame of your house that keeps letting in the cold draft in, but when you try to try to make it stick to the outside of your liquid oxygen/hydrogen fuel tank at mach 6, aventually it might bust ur damb space ship! Sometimes you can engineer the piss out of an item but you didn't account for the part that's going to break and muff the whole thing up. Quote Link to comment Share on other sites More sharing options...
boonman Posted February 3, 2004 Report Share Posted February 3, 2004 However Holyman, you are overlooking the fact that the clutch basket does not turn at nearly the same speed as the crank. It is not a 1:1 ratio. I understand what you are driving at here, that it will run longer and what not the faster it spins. And yes, it will. BUT, this only happens when the power is taken out of the equation. With a banshee, you get a power stroke every 180 degreees of crankshaft rotation. So, a heavy flywheel is not needed. THe clutch basket and crank shaft do not turn at the same RPM. There are gear and chain driven counterbalancers, but the shee does not utilize them... Quote Link to comment Share on other sites More sharing options...
Holyman Posted February 4, 2004 Report Share Posted February 4, 2004 Certainly you're not saying the clutch basket isn't bolted to the crank. Quote Link to comment Share on other sites More sharing options...
909 Posted February 4, 2004 Report Share Posted February 4, 2004 Thats precisely what he's saying. Were you under the impression the clutch was directly connected to the crank? Quote Link to comment Share on other sites More sharing options...
Holyman Posted February 4, 2004 Report Share Posted February 4, 2004 The clutch inner hub is attached to the crank, the discs and pressure plate drive the basket, the basket drives the trans. With the clutch in {lever pulled} the hub and steel clutch discs are part of the rotational mass. Once the clutch is engaged {let out} the entire clutch including the discs and basket become rotational mass driven by the engine. A weighted pressure plate would work just like a weighted flywheel. Like having one heavy tire and one light tire on the same banshee rear axle, if you spin one, you spin the other. Quote Link to comment Share on other sites More sharing options...
909 Posted February 4, 2004 Report Share Posted February 4, 2004 You're close. The clutch basket is driven by the gear running around the outside. The crank has a gear that drives it. Quote Link to comment Share on other sites More sharing options...
909 Posted February 4, 2004 Report Share Posted February 4, 2004 Here it is. Quote Link to comment Share on other sites More sharing options...
Holyman Posted February 4, 2004 Report Share Posted February 4, 2004 I stand corrected Is there such a thing as replacement basket ans drive gear with different ratios? Quote Link to comment Share on other sites More sharing options...
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