Free Magnesium Wheels

[Shazaam!]

How about a free front magnesium wheel with your next tire purchase?

Consider this:

3.5 x 17 Wheel Weights:

Ducati OEM aluminum 5-spoke .... 9.25 lbs
Marchesini magnesium 5-spoke ... 6.80 lbs
Weight Savings ................. 2.45 lbs


120/70ZR17 Tire Weights (Sport Rider Magazine June 2002)

Dunlop D207RR ............... 10.44 lbs
Pirelli Supercorsa............. 8.38 lbs
Weight Savings ................. 2.06 lbs

Dunlop D207RR ............... 10.44 lbs
Bridgestone BT-010 .......... 8.81 lbs
Weight Savings ................. 1.63 lbs

This seemingly small weight difference between the heaviest Dunlops and the lightest Pirellis or Bridgestones is even more important than a larger weight savings at the wheel.

Simply stated, the rotational inertia of a wheel or tire is proportional to the square of the distance the weight is placed from the axle. Because of this square-effect, the tire weight has more effect on the rotational inertia of the wheel-tire combination mainly because of its somewhat greater distance from the axle.

A 1.6 - 2 lbs. lighter front tire will give you the same handling improvement that you get by switching from an aluminum to a magnesium wheel.

Looking at it another way, you can negate the handling benefits of expensive light weight wheels by switching to a heavier tire.

This is also the best argument for choosing aftermarket wheels that have carbon fiber rims. When compared to all-magnesium wheels with the same weight, a carbon fiber rimmed wheel will have significantly lower rotational inertia that results in improved acceleration and handling.

(The similar construction of rear tires results in weight savings of less than a pound so you'll see a lesser improvement effect there.)

I'm not saying that tires should be chosen based on weight alone but given the very similar performance of high performance street tires, why not take the free mag wheel?

[Nigel Booker]

I'll still be sticking with the dunlops!

[psychlist]

Cant afford to just bin the "dry use only" Pilots fitted as original on my new toy but will be reverting to my fave Battlax's as soon as these wear out! From my experience of Michelins it wont be long!

:ninja:

[Rattler]

What about 208Gps?
Should I consider these to weigh the same as the 207RRs?

Or just go out to the garage and weigh them myself?;);););)

Tim

[Jon]

What about the air at 36 psi, :lol:

[thrustercat]

What tyres do we have to buy to get a free (real) magnesium wheel, or are
you just saying that buying a new lighter tyre will effectively give us the
same performance benefit as buying a magnesium wheel instead?
why not get both a new tyre (light weight), and also a set of carbon rimmed
wheels to go with them? then, braking, quickness of cornering /
flickability, and accelerating will all be much improved.

In addition to the inertial benefits of reducing tyre and wheel values,
there are additional improvements that can be made to the bike (works on
cars too) of reducing the unsprung mass, that is the mass that is on the
road side of the suspension.

This mass, if reduced, will also gain significant benefits for the
performance and handling (primarily handling) of the vehicle, as there will
be less mass that is not compensated for by the suspension. this will help
in holding the desired line through corners, with less slipping and sliding,
and less deflection off the chosen line due to bumps and deficiencies in the
road surface, it will also mean that there is less mass that is being
allowed to affect the vehicles handling, as the suspension works very hard
to not let the bikes mass affect these aspects. this is also why a stiff
setting on your suspension will actually have a detrimental effect on
handling, if it is set too stiff for your bike, the rider, and the types of
road the bike is being used on, as it is not able to absorb the bumps, so
gets thrown off the 'perfect' line.

[jodycraw]

what about the weight of other tyres then, like Pirelli Diablo, Dunlop 208's or BT 012's...
Are they more or less the same as the other models from same manufacturer?

[Jasper]

Stop being a tight scouser and buy some mags!That's as in wheels,not as in the toolbar options you put on my PC!!!:D

[Road Runner]

I have been happy with my Michelin Pilot sports so far never thought about the weight. I work in F1 and the Magnesium rims used in F1 have a life span of three years max if not damaged dose any no if that applies to our wheels. ?

Mark.. :sing:

[Jasper]

I had a really good chat with the guys at Dymag(even though i've got Marchis),and they said that basically if you look after them,they are no worse than alloy wheels.No bouncing up and down kerbs,watch the paint(as it seals against corrosion) etc.They have wheels that come back to them that are 25 years old!

[Edited on 27-9-2003 by Jasper]

[Triple Nine]

Originally posted by Jon
What about the air at 36 psi, :lol:

What about Helium:lol::roll:

[jodycraw]

i remember from school that compressed helium weighs more than compressed air anyway....

[Totto]

Originally posted by jodycraw
i remember from school that compressed helium weighs more than compressed air anyway....
Is it not something to do with Helium being less heat sensitive !

[DJ Tera]

why do balloons filled with helium rise then?

[Shazaam!]

The air in a tyre will weigh about seven times more than helium in the same tyre at the same pressure and temperature.

[Rob B]

It look like you have access to some data and I was wondering if yoy knew how much the 3 spoke Brembos weighed in at.

When you list the weight of the OEM 5 spokes I assume these are the as delivered items (as opposed to the forged items) that first appeared on the 2000 SPS and now grace everything including Monsters and STs?

Thanks,

Rob

[Shazaam!]

Marchesini magnesium 5-spoke ... 6.8 lbs ... 8.7 lbs. rear
Ducati OEM aluminum 5-spoke ... 9.3 lbs ... 12.0 lbs. rear
Ducati OEM aluminum 3-spoke ... 11.5 lbs ... 13.3 lbs. rear

Ducati lightened the wheels in 1999 compared to prior years. I don't know how much, but they said so in their '99 brochures. Could be just a few grams.

[Rob B]

Wow, so if I had the dosh, changing the Ally 3 spokes (with Dunlops) on my 888 for the new Marchesini Mag 10 spokes (with Bridgestones) would be like halving the current wheel mass. Wow.

Thanks.

[Duncan Disorderly]

Hi

When you talk about the Marchesini 5 spoke are you referring to the new Y shaped in light alloy that come on the 999/749s?

If not does any one know the weight of these to work out if its worth changing for magnesiums?

Thanks
Peter

[Mike Davis]

TOTTO NO

Your thinking of Nitrogen mate.

[Ned]

I intend to sort out some of my sprung weight first - ie the spare tyre I carry with me at all times around my waist.

Weight saving = 1stone
Cost saving = 100 pints = 300 quid

;)