Wheel knowledge - weights, offsets, tyre choices etc

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Lewy
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Wheel knowledge - weights, offsets, tyre choices etc

Post by Lewy » 13 May 2013, 22:49

Found this whilst searching the net, seems to have a database of loads of wheels, the sizes and weights. Sadly not offset or fitment but given that there's very little out there to show wheel weights it could be quite useful :thumbup:

Wheel weight database

Hope it helps someone :-bd

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Gus247
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Re: Wheel weights database

Post by Gus247 » 14 May 2013, 09:19

apparently mine weigh about 10k's each..... :) Nice find fella.
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neilx6
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Re: Wheel weights database

Post by neilx6 » 14 May 2013, 13:07

Some points to think about when considering wheels,outside of offset etc
1.What effect does the design have on brake cooling(amount of air that flows around caliper etc)
2.Is there enough clearance in design for big brake kits
3.Understand that there is a massive difference between a wheel designed for the track and a road wheel
4.Whilst a wheel needs to be light it also needs torsional strength
and finally
5.TYRES
If performance is your goal then putting on cheap or budget tyres is a NO NO.On larger diameter wheels with larger tyres it may shock you to know
that the tyre can weigh more than the alloy wheel FACT.There is a reason why performance brands are the price they are,they are generally lighter
than their cheaper counterparts,have different sidewall construction and in some brands cases such as Continental actually have different shoulder
profiles for a front to a rear tyre.
I'm afraid to say that whilst it's a good tyre and reasonably priced tyre Falkens don't cut it for performance as an example.They are very heavy and use
old technology for their sidewall construction,so stick these on a light weight wheel and the drive will be awfull....nothing to do with the alloy but the
tyre selection is incorrect for the goal.

Hope this helps :thumbup: :thumbup: :thumbup: :thumbup:

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Lewy
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Re: Wheel weights database

Post by Lewy » 14 May 2013, 13:42

Some great info there Neal, we'll start to turn this thread into a bit of a one stop wheel knowledge thread and make it a sticky :thumbup:

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Lewy
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Re: Wheel knowledge - weights, offsets, tyre choices etc

Post by Lewy » 14 May 2013, 13:48

Taken from the wheel weight database site:

Wheel Technology

Construction Techniques:

Forging (including SSF which is a true forging) results in a much stronger wheel. The wheel can therefore be made lighter than a cast wheel, while still maintaining superior strength. Multi-piece forged whees have forged centers and spun rims. Sometimes the rims are spun from forged metal, sometimes they are not. Be sure to ask the wheel manufacturer which technique they use to make their rims sections.

Casting can be done in a number of ways. The most prevalent are gravity casting (pour the metal into a mold), vacuum/counter-pressure casting (suck the metal into a mold) and low-pressure casting.

Relative wheel strengths are as follows: 1-piece forged, multi-piece forged, die (high-pressure) cast, vacuum cast, low pressure cast and gravity cast. The strengths are only relative because weight (or actual mass) affects a wheels’ strength, as does the actual design. Vacuum (counter-pressure) casting is used almost exclusively by BBS for most of their wheels. Revolution wheels are an example of low-pressure casting designs.

Offsets:

You generally want to stay at the same offset as your stock wheels. Changing offsets can result in a change in scrub radius and torque steer (FWD and AWD only).

1. When changing diameters and offsets, your number one concern is to make sure the wheel will fit with your current suspension and bodywork. Every car is different so check with other people who have your same car to determine what will fit with your brakes, suspension drop, body work, etc.

2. When going to a smaller offset wheel, toe-in must be increased (same as decreasing toe-out) to compensate.

3. Going to a smaller offset wheel will change the scrub radius. The only way to bring it back to stock is to increase the overall diameter of the wheel/tire assembly. This has nothing to do with wheel diameter, but everything to do with the rolling diameter of the tires.

4. Different offsets will cause the same wheel to weigh more or less. The general rule is that the lower the offset (less positive), the higher the weight because the hub face is thicker.



Tire Weights:

Tire weights are just as, if not more, important than wheel weights. Tires are further from the axis of the rotation and therefore have a larger effect on steering feel, suspension movement, acceleration and braking. The lightest tires that are commonly available that I know of are the Toyo T1S. The Pirelli Pzero Neros are also light, but not as light as the Toyos. Tire companies will have their weight information, but you will have to get transferred around a few times before finding someone who knows usually. Some heavier tires are Falken Azenises and Bridgestone S-03s. Also remember that larger diameter tires weigh more than smaller diameter tires. Something to think about when going with plus-sized wheels.



Performance:

The general rule of thumb is that for every pound of weight that you add in wheel/tire combo, it’s equivalent to adding 2x that amount of weight anywhere else in the car. This only applies to straight line accelerating and braking.

Weight also plays a large role in turning (gyroscopic effect) and in handling due to your suspension having to damp all of the road forces. When it comes to wheels and cars, lighter is always better for performance.

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DJ Syxx
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Re: Wheel knowledge - weights, offsets, tyre choices etc

Post by DJ Syxx » 14 May 2013, 14:43

Doesn't have my wheel info, but I already know what they weigh lol.
OZ Racing/CSL styled M3
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Prince
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Re: Wheel knowledge - weights, offsets, tyre choices etc

Post by Prince » 15 May 2013, 20:22

My old D Force LTW5s (17 inch, et40, 8.5J, forged) weighed just 7.5kg each. They were very light. Matched with some Yokohama AD08s made for awesome performance.
Matt
E46 M3
E60 530d

tukangkebun
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Re: Wheel weights database

Post by tukangkebun » 19 Jun 2015, 10:37

neilx6 wrote:Some points to think about when considering wheels,outside of offset etc
1.What effect does the design have on brake cooling(amount of air that flows around caliper etc)
2.Is there enough clearance in design for big brake kits
3.Understand that there is a massive difference between a wheel designed for the track and a road wheel
4.Whilst a wheel needs to be light it also needs torsional strength
and finally
5.TYRES
If performance is your goal then putting on cheap or budget tyres is a NO NO.On larger diameter wheels with larger tyres it may shock you to know
that the tyre can weigh more than the alloy wheel FACT.There is a reason why performance brands are the price they are,they are generally lighter
than their cheaper counterparts,have different sidewall construction and in some brands cases such as Continental actually have different shoulder
profiles for a front to a rear tyre.
I'm afraid to say that whilst it's a good tyre and reasonably priced tyre Falkens don't cut it for performance as an example.They are very heavy and use
old technology for their sidewall construction,so stick these on a light weight wheel and the drive will be awfull....nothing to do with the alloy but the
tyre selection is incorrect for the goal.
Image
Hope this helps :thumbup: :thumbup: :thumbup: :thumbup:
good ,, Thanks you very much for this help

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