Hardware update gained 15% range

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******
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Re: Hardware update gained 15% range

Post by ****** » Tue May 14, 2019 7:14 pm

I don’t think the weight is responsible. I am a very small person (weighing 46 kilos). So theoretically, if it was down to the wheel weight as quoted above, I would get the same range as an 86kg person on 18” wheels.


scm
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Re: Hardware update gained 15% range

Post by scm » Tue May 14, 2019 7:23 pm

You can see why Ian Callum designs cars to have big wheels, can't you? They look so much better.


sciencegeek
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Re: Hardware update gained 15% range

Post by sciencegeek » Tue May 14, 2019 9:59 pm

FENorway wrote:
Tue May 14, 2019 6:57 pm
sciencegeek wrote:
Tue May 14, 2019 6:39 pm
I think the most important parameter is the fact that there is much more mass further away from the axle, so a lot more energy is required to accelerate to the same radial speed. The wheel is probably also heavier overall.
18" 1022 with Mich Lat Tour 235/65 24,7 kilos
20" 5070 with GY Asymmetric 245/50 28,8 kilos
22" 5069 with Conti PC6 255/40 34,4 kilos

The tyres on 18 and 20 weighs the same. The difference is the rims.
Wow that's a huge difference ... and much of that weight is further away from the axle ...


sciencegeek
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Re: Hardware update gained 15% range

Post by sciencegeek » Tue May 14, 2019 10:00 pm

Goshdarnit wrote:
Tue May 14, 2019 7:14 pm
I don’t think the weight is responsible. I am a very small person (weighing 46 kilos). So theoretically, if it was down to the wheel weight as quoted above, I would get the same range as an 86kg person on 18” wheels.
Wheel weight has a much greater impact than 'dead' weight


*****
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Re: Hardware update gained 15% range

Post by ***** » Tue May 14, 2019 10:16 pm

FENorway wrote:
Tue May 14, 2019 3:56 pm
Did a hardware update today which will increase the range by almost 15%.
The update was done by FTTM(ferry to the mainland) and MTOTA(money transfer over the air)
Paid 950 euros for the update. I've only downloaded it to my garage and will install it to the car later. 20190514_161712.jpg
The same wheels I have :-)

I have ordered 20" for mine for the summer as range is so good anyway.

Not sure if I could have gone for 22" as I don't have air suspension.


smithy2167
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Re: Hardware update gained 15% range

Post by smithy2167 » Tue May 14, 2019 11:02 pm

Well FENorway, before you swap the wheels, can you do some controlled tests of consumption in various conditions with the 22's. Then repeat the tests as closely as possible with the 18's.

I'm personally quite skeptical that there'll be anything like 15% difference.


BillCB
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Re: Hardware update gained 15% range

Post by BillCB » Wed May 15, 2019 2:20 am

Skinny tyres have less rolling resistance. 22 inch wheels have fat tyres.
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smithy2167
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Re: Hardware update gained 15% range

Post by smithy2167 » Wed May 15, 2019 3:32 pm

BillCB wrote:
Wed May 15, 2019 2:20 am
Skinny tyres have less rolling resistance. 22 inch wheels have fat tyres.
Do they? The main contributor to rolling resistance seems to be flexing of the sidewall as the tyre rolls along the road. The low profile tyres have much stiffer sidewalls and so flex less - hence the harsher ride. Sure they are wider, but is rolling resistance really greater?

Anyway, rolling resistance only makes up about 20% of the power loss. If the wider tyres add say 20% to the rolling resistance, that's only a 4% increase in overall losses.

And the 40kg weight penalty for the bigger wheels only represents less than 2% of the overall weight of the car.

So that makes 6% ...

That's why i believe some real world testing is needed.


Pcheaven
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Re: Hardware update gained 15% range

Post by Pcheaven » Wed May 15, 2019 4:23 pm

I think the extra weight being at the end of the axel and not as a overall percentage may be the major contributing factor ( force mass and distance from force ) and they require more force to be rotated.

Google will probably explain it better.

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NightFox
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Re: Hardware update gained 15% range

Post by NightFox » Wed May 15, 2019 4:40 pm

It also depends on the distribution of weight across the diameter of the wheel - weight "further out" from the axle takes more force to rotate than the same weight closer to the axle. So you could have two wheels (including tyres) of the same overall diameter and the same weight, but the one with the weight distribution closer to its point of rotation will use less energy (not taking into account other factors such as rolling resistance and tyre wall flex)


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