Marvics installed, with pics

[grabntwist]

I just put on my magnesium Marvic Penta II's a couple days ago. I must say Damn!! what a difference!! Total weight savings was 16.2 lbs over stock. The bike stops better, flicks side to side transitions with ease, and also accelerates way quicker. You probably wouldn't believe it but the bike feels like a moto gp bike. Almost everytime you're on the throttle it'll float the front wheel up a few inches, if not all the way up towards the sky. My friend was amazed when he noticed my back wheel a few inches off the road and not spinnin' while I was braking for a turn.

 

[grabntwist]

rear wheel

 

[grabntwist]

sprocket/rearset.



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[grabntwist]

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[grabntwist]

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[BigBSBusa]

All that from a different set of wheels?

 

[MET]

They look great!!

 

[1127 TO 1299]

NICE!
wheels make a difference since every pound needs to accelerate twice: linearly and centrifugaly.
At what price?

 

[Haywood]

Nice!! Those look great! Are you running the M1 tires? Looks like you're leaning that bad boy over pretty far.. good grip?

 

[grabntwist]

All that from a different set of wheels?

Hope this helps.

Lighter wheels can improve the performance of your Race Bike in three ways;

1. Lighter wheels can make your bike faster

Think of it this way - imagine the amount of energy you need to spin the front tire of your car/truck when it's jacked up and off the ground. Now think about the energy it takes to spin the tire on your ten speed bicycle. Big difference right? The ten speed wheel spins easier because it weighs less! -Yes, there are variances - friction in the bearings, etc., but the biggest reason for the difference is the mass (weight) of the wheel/tire itself. It's the engine that spins the wheels/tires of your race bike. If it takes less energy to turn those wheels that horsepower can be used for other things - like greater top speed or increased acceleration.

2. Lighter wheels make your bike easier to turn

We'll delve into a little physics here to explain this, but we'll make it painless - When you turn, the bike goes from straight up and down to some degree of lean - some angle from vertical. Because of the gyroscopic effect of your wheels the bike tends to resist this change.That's right - those wheels turn into big gyroscopes when they spin! The "gyro effect" is what tends stand the bike up when you ride. When the wheels spin they make the bike want to stay up. You can demonstrate this on your bike - find a safe place and ride your bike at about 30 mph and take your hands off the bars. The bike stays up because of the gyroscopic effect of the wheels. As the bike slows the gyro effect lessens and if you keep your hands off - the bike tips. The amount of "gyroscoping" is dependent on two things - how fast your wheel/tires spin and - that's right - how much they weigh! One ounce of weight on the rim of a 17 inch rim turns into 25 lbs at 100 mph (here's where the physics guys would go into the "mass and acceleration" discussion, but we're going to skip it...) If your on a Harley the "gyro effect" is a good thing. But for us racers - we want the bike to tip - to change from vertical to lean - and the faster we can go from vertical to leaning the better. That's what is meant by a bike's "turn in" ability. The easier it is to lean into that corner the easier it is to take it faster. We're not about to reduce the speed of the wheel, so to lessen the gyro effect we reduce the weight of the "spinning mass".This is usually the most noticeable difference after changing to lighter wheels. Racers say the bike feels lighter when it weighs virtually the same - it just fights you less....

3.Lighter wheels help your suspension work better

You may think that the springs in your front/rear suspension hold your bike off the ground - it does seem logical doesn't it? They don't - solid bars could do that. Try to visualize it this way - the springs try to hold the tire in contact with the road - they push the tires down. But - the road has imperfections, some big (bumps/ripples), some small (imperfections in the surface) that try to "bounce" your wheel/tire off. When your tire bounces, even a teeny tiny bit, your traction goes to zero! All of this bouncing is really just up and down motion that is starting and stopping. Again physics tells us that the energy required for all this starting and stopping is a function of (of course) weight. This what all that talk about unsprung weight is about when you read it in the magazines. When your springs have to handle less weight they will naturally do a better job of holding the tire against the road. To us road racers that means greater traction - the rubber is in contact with the surface more of the time. That means better grip in the turns which translates to increased corner speed and lower lap times. Better traction also means less wheelspin and that means better drive out of the turns - an additional bonus.

 

[grabntwist]

NICE!
wheels make a difference since every pound needs to accelerate twice: linearly and centrifugaly.
At what price?

my set-up goes for about 2,300 hundred without tires. I got them for alot less.

 

[grabntwist]

Nice!!  Those look great!  Are you running the M1 tires?  Looks like you're leaning that bad boy over pretty far.. good grip?

The tires got great grip, but they don't seem like they're gonna last too long. They're Rennsports.

 

[BigBSBusa]

All that from a different set of wheels?

Hope this helps.

Lighter wheels can improve the performance of your Race Bike in  three ways;

   1. Lighter wheels can make your bike faster

Think of it this way - imagine the amount of energy you need to spin the front tire of your car/truck when it's jacked up and off the ground. Now think about the energy it takes to spin the tire on your ten speed bicycle. Big difference right? The ten speed wheel spins easier because it weighs less! -Yes, there are variances - friction in the bearings, etc., but the biggest reason for the difference is the mass (weight) of the wheel/tire itself. It's the engine that spins the wheels/tires of your race bike. If it takes less energy to turn those wheels that horsepower can be used for other things - like greater top speed or increased acceleration.

   2. Lighter wheels make your bike easier to turn
 
We'll delve into a little physics here to explain this, but we'll make it painless - When you turn, the bike goes from straight up and down to some degree of lean - some angle from vertical. Because of the gyroscopic effect of your wheels the bike tends to resist this change.That's right - those wheels turn into big gyroscopes when they spin! The "gyro effect" is what tends stand the bike up when you ride. When the wheels spin they make the bike want to stay up. You can demonstrate this on your bike - find a safe place and ride your bike at about 30 mph and take your hands off the bars. The bike stays up because of the gyroscopic effect of the wheels. As the bike slows the gyro effect lessens and if you keep your hands off - the bike tips. The amount of "gyroscoping" is dependent on two things - how fast your wheel/tires spin and - that's right - how much they weigh! One ounce of weight on the rim of a 17 inch rim turns into 25 lbs at 100 mph (here's where the physics guys would go into the "mass and acceleration" discussion, but we're going to skip it...) If your on a Harley the "gyro effect" is a good thing. But for us racers - we want  the bike to tip - to change from vertical to lean - and the faster we can go from vertical to leaning the better. That's what is meant by a bike's "turn in" ability. The easier it is to lean into that corner the easier it is to take it faster. We're not about to reduce the speed of the wheel, so to lessen the gyro effect we reduce the weight of the "spinning mass".This is usually the most noticeable difference after changing to lighter wheels. Racers say the bike feels lighter when it weighs virtually the same - it just fights you less....

   3.Lighter wheels help your suspension work better

You may think that the springs in your front/rear suspension hold your bike off the ground - it does seem logical doesn't it? They don't - solid bars could do that. Try to visualize it this way - the springs try to hold the tire in contact with the road - they push the tires down. But -  the road has imperfections, some big (bumps/ripples), some small (imperfections in the surface) that try to "bounce" your wheel/tire off. When your tire bounces, even a teeny tiny bit, your traction goes to zero! All of this bouncing is really just up and down motion that is starting and stopping. Again physics tells us that the energy required for all this starting and stopping is a function of (of course) weight. This what all that talk about unsprung weight is about when you read it in the magazines. When your springs have to handle less weight they will naturally do a better job of holding the tire against the road.  To us road racers that means greater traction - the rubber is in contact with the surface more of the time. That means better grip in the turns which translates to increased corner speed and lower lap times. Better traction also means less wheelspin and that means better drive out of the turns - an additional bonus.

Thanks for the run down, 'bro! My physics and mechanical engineering days were starting to come back to me and I will be dreaming of those crazy equations plus the coefficient of drag! Hope it doesn't keep me up too late!!!

 

[MeltDownZ]

The bike stays up because of the gyroscopic effect of the wheels. As the bike slows the gyro effect lessens and if you keep your hands off - the bike tips.

Just nit-picking here but the gyroscope effect does not make the bike want to stand up. The gyroscope effect makes the bike resist leaning or other change in direction but it will not straighten it back up. It's the drag of the front wheel contact patch that stands the bike up. The contact patch which is dragging behind axis of the front forks steers back and forth continually straightening the bike. As proof, if you reversed the rake of the front forks so the contact patch were in front on the axis, the bike would fall right over no matter how fast the wheels were spinning.

Todd

 

[phatjoe]

SICK rims they cost more than the set of 4 18"s on my jetta

 

[fstbusa]

yeah no kidding I would save up slightly more and go boost for that much.

 

[monsterspeedfreak]

Pricey, but if they perform that well, it was worth it!!!!

Bike looks good dude!!!!

 

[grabntwist]

yeah no kidding I would save up slightly more and go boost for that much.

Boost is not the answer my fellow Busa brother. Rideability is... with all I have in my bike I could have easily added a turbo. I chose to go all motor. Just a choice, nothing more. Boosted Busa's seem to be a bit finicky for me. They also seem really hard to ride agressivly. They run like stock bikes and all of a sudden the boost builds and wham!!! you got 300hp to the wheel and don't know what to do with it.

 

[busa1300nut]

I think for $2300.00, they should look a lot better than that.

 

[streaker00]

Looks great!!!!! My offer still stands. We really should race for them. You've got more HP but I'll still give you the hit. I'll see you at the track one of these days.