Pictures: M5 E60 with Hartge wheels and spoiler in Interlagos Blue - Page 4 - The Unofficial BMW M5 Messageboard (m5board.com)

absent · 24th September 2005, 04:30

Quote:

Originally Posted by Mvious

Wow! I am jealous! What a beautiful machine!

I would not go so far as calling it "beautiful" or "pretty".
"Mean and masculine" sounds more like it ......
Would probably add "intimidating" also.....
It's got that look of :"don't f##k with me "

Gustav · 25th September 2005, 16:24

Is this correct calculations?

I am assuming that the 21 and 19 inches are exactly on the inch in diameter, and that profile of the tyre is the percentage of the width. 1 inch = 25,4 mm.

Quote:

Originally Posted by Gustav

Speaking of 21 inch Hartge, I realise even though they are 21 inch, the diameter (important for acceleration) is smaller than the standard M5 E60! So it is only that added weight of the wheels tht hampers performance.

My calculations:

Hartge wheels:

Front: 686, 4 mm
Rear: 680,9 mm

BMW M5 standard wheels:

Front: 686,6 mm
Rear: 682,1 mm

Formula: (width [mm] * profile [%]* 2) + (diameter[inch] * 25,4 [mm])

Units: mm = metric millimeter and inches

Could this be correct?

Wolverine · 25th September 2005, 22:49

Quote:

Originally Posted by Gustav

Is this correct calculations?

I am assuming that the 21 and 19 inches are exactly on the inch in diameter, and that profile of the tyre is the percentage of the width. 1 inch = 25,4 mm.

Yes, these are the correct calculations. The 1.2mm difference in diameter of the rear tires is insignificant. It amounts to a few thousand miles of treadwear on the OEM tires.

More importantly, I'd like to know how much those wheels weigh. I'm assuming they are cast, not forged. If so, they could be fairly heavy.

Gustav · 25th September 2005, 22:53

Thanks Wolverine for confirming my calculations.

Yup, we can be all sure that they are heavier than standard. Also, it is important to see where the majority of the mass is: near the rotational centre or more "radially out" which is worse.

But nice to hear that the diameter of the 21 wheels wont be a negative factor towards perfromance.

citystar · 26th September 2005, 00:18

Another factor to consider is the fact that having larger rims pushes more mass farther out from the center of the wheel which will hinder performance. Like the spinning balerina that spins faster as she brings her arms closer to her center, smaller diameter rims will give better performance because it will contain more of the mass towards the axis of which it rotates on. Just something to think about, but I absolutely love the look of 21's on the E60 dropped and inch.

Gustav · 26th September 2005, 00:20

citystar, that was a very good analogy you did there with the ballerina.

citystar · 26th September 2005, 07:25

Quote:

Originally Posted by Gustav

citystar, that was a very good analogy you did there with the ballerina.

Haha thank you very much.

Gustav · 28th September 2005, 00:32

Three x Silverstone II outside Hartge Headquarters in Beckingen, Germany.

Gustav · 14th December 2005, 18:11

And one in black:

With the full Hartge kit

Shipping worldwide incl. USA. Installation manual is included and the parts can be installed at any dealer.

If you choose to install the kit at Hartge's facilities in Germany (Beckingen) Hartge can arrange a Hotel for you the night before and will provide you with a car during the time of conversion to see the nice countryside as they have nice wine in the region.

If you are lucky you might even can meet the founder, Mr Herbert Hartge.

Please contact Mr Jörg Wey at verkauf@hartge.de or call Jörg at Hartge in Germany (speaks English).

Tel.+49 6835/506-11 * Fax +49 6835/506-17

EBuyuk · 14th December 2005, 18:57

I wonder how those wheels would look like on a white M5....