Light weight wheels, interesting findings.

[rtbiscuit]

icame across this else where, its an extract from a recent fast ford magazine that had some interesting information and tests done on light weight wheels. Anyway, I thought a few of you may be interested in this...

 

They have a very good test in this month's edition. They have a tuned Fiesta ST that is running 215bhp. They changed the standard ST wheels for Team Dynamic Pro Race 1.2s which are altogether 12kg lighter. They mention that 12kg unsprung weight is equivalent to around 48kg weight saving from the chassis. They undertook 4 tests -

 

Test 1 - Braking. 60-0mph and 100-0mph

Test 2 - Handing. A timed lap around a circuit

Test 3 - Standing start acceleration to 60mph

Test 4 - In gear acceleration. 30-80mph

 

Results - All tests were performed 3 or 4 times and the times were then averaged. Results were gained using a Racelogic Performance Box.

 

Test 1 - Before 60-0 = 3.2s Before 100-0 = 5.3s G = 0.97

After 60-0 = 3.0s After 100-0 = 4.8s G = 1.07

 

Test 2 - Before = 1:28.6 After 1:24.3

 

Test 3 - Before 0-60 = 6.9s Before 0-100 = 17.8s Quarter mile = 15.7 @ 94mph

After 0-60 = 7.4s After 0-100 = 18.0s Quarter mile = 15.9 @ 94mph

 

Test 4 - Before 30-80 = 8.8s After 30-80 = 8.3s

 

 

I'm sure you'll agree there is some intersting results there. Quite a difference on the timed circuit. They said they thought the 0-60 times were down on the standard wheels as there was less mass for the engine to turn, therefore the wheels tended to spin more when applying the accelerator.

 

Hope this is of some use to some people!

[docwra]

Was this the Redline test? Stav mentioned there were some pretty impressive results. Light wheels are the way forward unless you are a 0-60 legend then.

[CaptainSensible]

That's really interesting, makes me glad I've never changed my rays!

 

I've also wondered if having bigger wheels affects speed/handling as you have more rubber down but more weight where you don't really want it.

[ug45cwb]

Interesting they make the 0-60 time significantly worse but improve all the other numbers

[Husky]

interested on how the tyres were matched?

[andlid]

interested on how the tyres were matched?

me too, they'd need to have swapped the rubber there and then to something they wanted to test it with. either way weight saving is the way to go, kinda goes without saying really. therefore not replacing current setup with anything else for the moement then rays.

[rtbiscuit]

interested on how the tyres were matched?

 

my guess is that if it was to be an accurate test then they must have run the same tyres on both wheels i.e. brand and model of tyre. without the original article i don't know.

 

Interesting they make the 0-60 time significantly worse but improve all the other numbers

 

yep less weight to move so the car lights them up easier

 

That's really interesting, makes me glad I've never changed my rays!

 

I've also wondered if having bigger wheels affects speed/handling as you have more rubber down but more weight where you don't really want it.

 

there are lighter wheels than the rays out there. all have an effect and change the characterisitcs.

 

Was this the Redline test? Stav mentioned there were some pretty impressive results. Light wheels are the way forward unless you are a 0-60 legend then.

 

i think it was a fast ford issue from this month. must admit i'm not a fan of 0-60 drag racing, wheres the fun in going fast in a straight line, any moron can do that. going fast round a corner now thats a whole different ball game.

[rob63]

I recently put a set of BST carbon fibre wheels on my motorcycle...you'll really notice all of the benefits above and some! I wouldn't have got the same performance gain if I'd have spent the same money on engine tuning.

[ATTAK Z]

I recently put a set of BST carbon fibre wheels on my motorcycle...you'll really notice all of the benefits above and some! I wouldn't have got the same performance gain if I'd have spent the same money on engine tuning.

 

on a bike you'll feel the difference due to the gyroscopic effect of the rotating wheel as well ........ a lighter front wheel will need less effort (force) to turn in the plane normal to the rotating plane of the wheel .... so the bike will feel more agile

[Ekona]

Great post Rich, thanks for sharing

 

 

I'm going to edit the title too, hope you don't mind.

[ATTAK Z]

Great post Rich, thanks for sharing

 

 

I'm going to edit the title too, hope you don't mind.

thanks it was doinme'edin

[andlid]

I recently put a set of BST carbon fibre wheels on my motorcycle...you'll really notice all of the benefits above and some! I wouldn't have got the same performance gain if I'd have spent the same money on engine tuning.

 

had to check that out... and yeah still bleeding expensive! whats the weight difference on your bike on the tyres?

 

Price: £2,586.00 Including VAT at 17.5%

 

can get a turbo setup on the R6 for that mate!

[marzman]

When i went from my JDM 17" wheels to my cheapo 19" wheels, the difference was horrendous! I soon sold them and returned to the 17's. I'll never be buying 19's again, unless they're super lightweight.

[rtbiscuit]

Great post Rich, thanks for sharing

 

 

I'm going to edit the title too, hope you don't mind.

 

yeah no worries, i'm guessing it was a keying error; thats the problem with homer simpson hands

 

 

on a bike you'll feel the difference due to the gyroscopic effect of the rotating wheel as well ........ a lighter front wheel will need less effort (force) to turn in the plane normal to the rotating plane of the wheel .... so the bike will feel more agile

 

very true gyroscopic effect plays a big part like rotational mass, almost more so than unsprung and sprung weight

 

Unsprung weight is one thing, rotational mass is quite another.

 

Reducing rotational mass is the key one here because not only do you have to drag the mass of the component upto the speed of the car (as in it is part of the car), but you also have to spin it up to its rotational speed.

 

Hence you have to perform two sets of acceleration on it!

 

Of course, what we actually need to know is the angular momentum.

 

This will give you the energy used to spin up the component.

 

the higher your angular momentum, the more your gyroscopic effect.

 

Hence, the faster your heavy large diameter wheels spin, the more resistance they have to having their direction altered.

 

This can cause allsorts of issues with handling.

 

The Powerball works on gyroscopic forces and if you have ever had a go, you know how difficult it can be to manipulate when spinning.

 

If your an IT techie, pick up a hard drive when it's on, gently move it about and you can feel the gyro resisting/magnifying your movements (I AM NOT RESPONSIBLE FOR YOUR DATA LOSS IF YOU DO THIS AND DROP THE DRIVE smile.gif )

 

In addition, the engine, clutch, flywheel spinning will cause a yawing effect. Granted, not mega, but it's present and it's something to be minimised (can be quite a serious problem on motorbikes, not to mention Helicopters and radial engined aircraft!).

 

So when people go on about 19" wheels wrecking the handling, you now know why

 

I recently put a set of BST carbon fibre wheels on my motorcycle...you'll really notice all of the benefits above and some! I wouldn't have got the same performance gain if I'd have spent the same money on engine tuning.

 

one of the heaviest parts of the wheel is actually the tyre, i'm sure those of you who have light weight wheels will tell you, you could probably pick one alloy up with 1 finger, but add a tyre and its a whole different matter.

[ATTAK Z]

 

In addition, the engine, clutch, flywheel spinning will cause a yawing effect. Granted, not mega, but it's present and it's something to be minimised (can be quite a serious problem on motorbikes, not to mention Helicopters and radial engined aircraft!).

Hence why outboards are set off centreline on boats and why high powered dragsters twist the chassis on take off

 

 

[andlid]

dont forget the air too

[ATTAK Z]

dont forget the air too

sorry ?

[rtbiscuit]

i'm guessing in the weight of the wheel andlind is addin gthe air as well.

 

from another site i got this list of wheel and tyre weights,

 

Tyre weights of AD08s from here http://www.yokohamatire.com/tires/spec. ... OVA%20AD08

 

Tyres

Fronts

16" 21lb

17" 22lb

 

Rears

16" 22.9lb

17" 25.5lb

 

Wheels

Front

16" Cast 17.5lb

16" BBS 13.3lb

17" '04 17.6lb

 

Rear

16" Cast 18.6lb

16" BBS 14.3lb

17" '04 20.5lb

 

Total

Front

16" Cast 38.5lb (17.5kg)

16" BBS 34.3lb (15.6kg)

17" '04 39.6lb (18.0kg)

 

Rear

16" Cast 41.5lb (18.8kg)

16" BBS 37.2lb (16.9kg)

17" '04 46.0lb (20.9kg)

 

someone elses research, but goes to show how much the tyres weigh

[andlid]

dont forget the air too

sorry ?

fill her up with hydrogen

[andlid]

i'm guessing in the weight of the wheel andlind is addin gthe air as well.

 

from another site i got this list of wheel and tyre weights,

 

Tyre weights of AD08s from here http://www.yokohamatire.com/tires/spec. ... OVA%20AD08

 

Tyres

Fronts

16" 21lb

17" 22lb

 

Rears

16" 22.9lb

17" 25.5lb

 

Wheels

Front

16" Cast 17.5lb

16" BBS 13.3lb

17" '04 17.6lb

 

Rear

16" Cast 18.6lb

16" BBS 14.3lb

17" '04 20.5lb

 

Total

Front

16" Cast 38.5lb (17.5kg)

16" BBS 34.3lb (15.6kg)

17" '04 39.6lb (18.0kg)

 

Rear

16" Cast 41.5lb (18.8kg)

16" BBS 37.2lb (16.9kg)

17" '04 46.0lb (20.9kg)

 

someone elses research, but goes to show how much the tyres weigh

low profile so

[rtbiscuit]

you have to keep the rolling radius the same, so to run lower profile you have to fit bigger wheels.

 

what is taken away with one hand; is given back with the other hand.

[ATTAK Z]

dont forget the air too

sorry ?

fill her up with hydrogen

did you see the Hindenburg crash ?

[rtbiscuit]

best to put nitrogen in your tyres. wont make them lighter, but they won't be as reactive to heat. and so the pressures won't change as the heat does.

[andlid]

best to put nitrogen in your tyres. wont make them lighter, but they won't be as reactive to heat. and so the pressures won't change as the heat does.

great for tracking

 

why keep the radius the same?

[rtbiscuit]

best to put nitrogen in your tyres. wont make them lighter, but they won't be as reactive to heat. and so the pressures won't change as the heat does.

great for tracking

 

why keep the radius the same?

 

if your rolling radius is way out, so your speedo will be as well. you'll be travelling a further distance per revolution compared to what the speedo will be reading.

 

or it works in reverse if you go smaller.