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I've always known Spoked wheels to be better on dirt bikes because they hold up better over jumps and such. This is important because many times a street ridden SM will jump curbs and such. Spoked wheels are also said to have better flex characteristics for certain types of riding.

All modern sport bikes of course use a cast aluminum wheel. They are light, tubeless, and of course look cool pretty cool as well. But I've personally experienced them failing and it's not good. Here is a pic of my SV1000S wheel that broke on me at around 70 mph on completely flat ground. It was not pretty and I'm pretty sure I lost a few IQ in that one when I flew over the handlebars.



I understand the aftermarket Forged Aluminum Marchesini's are built to withstand SM forces but I don't know if that includes the random curb jumping.

Also, I guess Alpina builds a lightweight, tubeless spoked wheel that approaches the weight of the lightweight Forged Aluminum wheels?

Anyone know the advantages and disadvantages to both? What do the pro racers run?

Thanks!
 

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a spoked wheel survives massive impacts because it flexes.

for a cast wheel to survive similar massive impacts, it has to be strong enough to absorb the full impact without permanently deforming... the only wheels that even seem to have the possibility of taking hte same impacts are the Marchesini.. and i only say that because theres not alot of gaps between the several "spokes" of the rim and they are forged.
still, if i PLANNED on jumping it, bashing things, etc.. i would go with spoked rims... if for no other reason....if you hit a square edge curb dead on wrong, its easier to fix.






besides... spoke wheels look cooler.
 

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Skeletor!

I'm thinking about putting those rims on my 510 as well. Do you have any pictures that I can look at? Did you get them at a good price?

Thanks!
 

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besides... spoke wheels look cooler.
And they make a better noise when you let a playing card click off them! :Funny: :Funny: :lol: :lol: :Funny: :Funny:
 

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Forged Aluminum wheels are 10 times stronger then a cast wheel

a Forged Aluminum wheel can take hits better too,yes any thing can bend
but its cheaper to repair a spoked rim them a Forged Aluminum rim.
only one place in the usa repairs Forged Aluminum wheels with no heat, just presses-

its comes down to money evey time-my carrozzeria's cost twice as much
as a spoke set up

funny thing is carrozzeria's are 8.8 lbs lighter then the Marchesini's
Marchesini has been around alot longer but have had more problems with a bad design,but they fixed it-Marchesini's also cost more then carrozzeria's

when your bike cost around 6 to 7grand- most guys cant afford another 2grand for new forged wheels

i have had carrozzeria's for almost two years and im on my second set only due to the upgrade of the new 5.0 rear rim

if you can afford them they are the best thing out there,your bike will turn in much better the spoke rims-less unsprung weight
 

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people tend to forget that there is a difference between cast and forged aluminium...

practically all oem fitted sportsmotorcycle wheels are cast... castings are high in silicium and therefor are very stiff but brittle.

Forgings(sp?) are tougher, but again, there are cold and hot forgings, wherein a cold forge is usually lots stronger than a hot forge.

In the end, as consumer, you never know what you got... i mean go figure... marchinesi is not going to tell us how they made the wheels.

But anyways, a construction is as strong as its weakest component. a spoked wheel has an aluminium (rolled/forged) outter edge too, which, if being of the same properties, will bend just as quick as a forged wheel's outter edge.

Basic rule is that most stainless steels usually are a lot tougher than aluminium (in whatever alloy) so a good spoked wheel will be tougher than a forged one, but denting the edges will happen just as quick; they are not meant to handle those pointed-forces (dunno how to translate)
 

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people tend to forget that there is a difference between cast and forged aluminium...

practically all oem fitted sportsmotorcycle wheels are cast... castings are high in silicium and therefor are very stiff but brittle.

Forgings(sp?) are tougher, but again, there are cold and hot forgings, wherein a cold forge is usually lots stronger than a hot forge.

In the end, as consumer, you never know what you got... i mean go figure... marchinesi is not going to tell us how they made the wheels.

But anyways, a construction is as strong as its weakest component. a spoked wheel has an aluminium (rolled/forged) outter edge too, which, if being of the same properties, will bend just as quick as a forged wheel's outter edge.

Basic rule is that most stainless steels usually are a lot tougher than aluminium (in whatever alloy) so a good spoked wheel will be tougher than a forged one, but denting the edges will happen just as quick; they are not meant to handle those pointed-forces (dunno how to translate)

your dead on the money, did better then me
 

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what does that mean? my english is limited and i dont understand those em... well... 'sentences' that you use to say something else
 

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... i mean go figure... marchinesi is not going to tell us how they made the wheels.
Here is a look into the process.... The biggest difference is the 15,000 ton multi directional press.... They are working on some extremely new and advanced tech stuff that should be out in about 2 more years...

Forging: Another way of forming aluminum and magnesium into a wheel is to use high pressure forging techniques which aligns the fiber of the material into the direction needed for maximum strength.. By compressing the material in a 15,000 ton press a lighter and stronger product can be produced because less material is needed to make the wheel.

Unique advantage of the Marchesini Three Dimensional Forging Process: When you forge a piece you normally come straight down and cut the part out like you would make a cookie from a cookie mould.

This process is called "open die" forging and is the simplest and lowest cost way of forging. You then have to machine out the well and bead area which interferes with the fiber structure of the material causing a loss of strength.

The forging process used to make the Marchesini wheels uses a precision three piece mould, "closed" die process which is "more expensive and complex," to not only form both sides but also to form the well and bead seat of the wheel. This process makes a superior wheel with higher mechanical properties.

However, you can understand the complexity of making a three piece mould that must have side sliders operating under 15,000 ton pressures. The Marchesini forging three piece closed dies are precision, complex, and very expensive.

The other advantage of the forged wheels is that all surfaces are "machined" which creates a precision wheel. The trueness of a forged wheel adds to the overall performance of the wheel.

Jeff

:thumbup:
 

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However, you can understand the complexity of making a three piece mould that must have side sliders operating under 15,000 ton pressures.
oh boy i have been doing that for a year... designing moulds, for plastics but also for aluminium/magnesium injection moulding... it is HORRIBLE.... offcourse the forging process is a lot different, but only more demanding for the moulds... imagine what a work and research.


I wonder if they dont roll the main part of the wheels?
 

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We have TONS of info on all wheels and Mfg processes used. We have sat in some very high level meetings with all kinds of wheel mfgs.

If anyone saw us at the Indy show, I'm sure I handed you the MotoGP marchesini wheel.... It's absolutely sick how light it is....

How do the different processes compare in the areas of weight and mechanical properties (stiffness) under different riding conditions?

Type Wheel Weight Result*
Weight:
Cast 6.00 lbs. 0
Forged Magnesium 4.74 lbs. -20%
Carbon Fiber 3.86 lbs. -35%

Radial Stiffnes:
Cast 6.00 lbs. 0
Forged Magnesium 4.74 lbs 0
Carbon Fiber 3.86 lbs. -3%

Moment of Inertia:
Cast 6.00 lbs. 0
Forged Magnesium 4.74 lbs. +20%
Carbon Fiber 3.86 lbs. +29%

Torisional Stiffness (bending):
Cast 6.00 lbs. 0
Forged Magnesium 4.74 lbs. +5%
Carbon Fiber 3.86 lbs. 0

Moment of Inertia:
Cast 6.00 lbs. 0
Forged Magnesium 4.74 lbs. +3%
Carbon Fiber 3.86 lbs. -7%

*Stiffness means the amount of movement of the material in the wheel under different riding conditions. We are using the cast wheel as the "O" benchmark and computing the amount of stiffness of the forged and carbon wheels. A + means that the wheel type is better, a - means that it is less stiff.

Cast: As you can see the cast wheel offers a lot of performance and value in the areas of weight and mechanical performance.

Forged: The forged magnesium wheel is lighter and offers more stiffness. The rim is also a little lighter which reduces dynamic weight and adds to the overall performance. The forged wheel because it is completely machined also runs very true which improves the performance of the wheel.

Carbon Fiber (unavailable): The carbon fiber is the lightest of the three and is stiffer in most areas. It is also the most expensive and can only be used in certain race classes. It is also difficult to test carbon fiber after an accident has been experienced to make sure the wheel is safe to reuse. Carbon Fiber should be used in specific applications by experienced riders who will take the extra care that is necessary.However, carbon fiber offers high performance and will appeal to the rider who wants the maximum performance in a wheel technology and is not concerned about cost or extra maintenance.

TRACK RESULTS:
The Factory teams have been using and testing the Marchesini forged magnesium and carbon fiber wheels since last August. The results are as follows with each type of wheel. Again, the 5 spoke Marchesini cast wheel is the benchmark.

Forged Magnesium: 1 Second less time. per lap.
Carbon Fiber: 2 Seconds less time per lap.

Type of Track: The more curves in the track the more time will be reduced by the forged magnesium and carbon fiber wheels.
 

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I wonder if they dont roll the main part of the wheels?
The 15,000 ton (15,000 TON) press is huge - like 2 1/2 stories high... It actually shakes the ground when it comes down... I thought we were good because we have a 210 ton press...

The forged wheels are not rolled at all...

Also, another way a spoke wheel vs. a mag type wheel differs is that "any" impact at the bottom of the wheel (like a pot hole hit) is directly transfered throughout the entire mag type wheel... since it's basically solid, it's up to the air in the tire (low pressure is leading cause of bent rims) then the suspension, then the riders hands/arms to absorb any "hit". With a spoke wheel it's the same but you have added, spoke "flex" at the top of the wheel (not the bottom) when you take a "hit"...
 

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Wouldn't the added flex of the spoked rims allow some suspension slop for turning?

Or does that contribute to this notion of "tuned flex" for mid corner bumps.

I only run on road corses, no jumping at all. I'm wondering if going forged vs. spoke would allow a bit more precison for the really long, fast, sweeping turns that I run (top gear, about 100 MPH??? on the side of the tire).
 

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Type Wheel Weight Result*
Weight:
Cast 6.00 lbs. 0
Forged Magnesium 4.74 lbs. -20%
Carbon Fiber 3.86 lbs. -35%

Radial Stiffnes:
Cast 6.00 lbs. 0
Forged Magnesium 4.74 lbs 0
Carbon Fiber 3.86 lbs. -3%

Moment of Inertia:
Cast 6.00 lbs. 0
Forged Magnesium 4.74 lbs. +20%
Carbon Fiber 3.86 lbs. +29%

Torisional Stiffness (bending):
Cast 6.00 lbs. 0
Forged Magnesium 4.74 lbs. +5%
Carbon Fiber 3.86 lbs. 0

Moment of Inertia:
Cast 6.00 lbs. 0
Forged Magnesium 4.74 lbs. +3%
Carbon Fiber 3.86 lbs. -7%

Jeff,

Do you have comparison info for spoked wheels?

Are not spoked wheels lighter than cast yet heavier than the other two?
 

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people tend to forget that there is a difference between cast and forged aluminium...

practically all oem fitted sportsmotorcycle wheels are cast... castings are high in silicium and therefor are very stiff but brittle.

Forgings(sp?) are tougher, but again, there are cold and hot forgings, wherein a cold forge is usually lots stronger than a hot forge.

In the end, as consumer, you never know what you got... i mean go figure... marchinesi is not going to tell us how they made the wheels.

But anyways, a construction is as strong as its weakest component. a spoked wheel has an aluminium (rolled/forged) outter edge too, which, if being of the same properties, will bend just as quick as a forged wheel's outter edge.

Basic rule is that most stainless steels usually are a lot tougher than aluminium (in whatever alloy) so a good spoked wheel will be tougher than a forged one, but denting the edges will happen just as quick; they are not meant to handle those pointed-forces (dunno how to translate)
 
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