Sponsored by The Tire Rack

[BerkTechnology]

Berk Technology has been on a 1 year mission for a wheel manufacturer to step up and produce a 135i specific wheel for the 1er community. We are on our 4th set of wheels for our race car and we have tried about 10 different tire sizes & wheel combos in various permutations. That's my CV when it comes to knowledge in 135i wheel/tire fitments. I think we finally have reached our goal, we just need the backing of the 135i community to make sure these reach us in a timely manner! The more support we get the quicker this project will arrive on our doorsteps.

Enter Apex wheels......

We met up with Eddy of Apex wheels at Bimmerfest 2009. Apex has been producing BMW & Mini wheels for a few years now and we proposed the idea of making a 135i wheel for us. A few emails and phone calls later and Apex is now on board to produce us a 135i specific wheel!

A few manufacturers have attempted to use existing molds and just change the offsets but the unusually high offset that we require in the rear of the 135/128/120 necessitates a new wheel to be created from the ground up. The existing molds out there that are designed for lower offsets (30-45mm) simply don't have enough material built into them to shave the inner face/hub of the wheel to achieve the +60mm offset that the 135i NEEDS to have. Eddy & Apex will be designing this wheel from a clean sheet that will allow the wheels to be built with enough material and strength.

To reiterate, Berk Technology has tried more wheel and tire fitments and taken more measurements on the chassis than even the wheel manufacturers and here is what we've decided upon in conjunction with Apex wheels. This is what I believe would be the perfect setup for 95% of us and is as plug and play as possible for the performance orientated wheel/tire setup.

Front: 18x8.5 +38
Rear: 18x9.5 +62

The front wheel will allow us to use anything from the factory sized 215/40/18, all the way up to a 255/35/18.

The rear wheel will allow us to use anything from a skinny 235/40/18 all the way up to fat 265/35/18 or possibly 275/35/18 sized rubber with tons more grip!

So post your comments and questions here so we can all discuss!

The CAD drawings of the wheels:
Front - 18x8.5 +38


Rear - 18x9.5 +62


The actual GB thread is hereThis thread here is more of an open round table discussion.
http://www.1addicts.com/forums/showthread.php?t=270937

Our car is currently on Dunlop Star Specs 255/35/18 front, 265/35/18 rear. (awesome tire BTW) Enkei 18x8.5 +38 with a 5mm spacer, 18x9.5 +58. With these Apex wheels we would have an additional 4mm of fender clearance and we just MIGHT be able to finally run a 275 in the rear!

[M2BMW]

Originally Posted by Phiberglass

Awesome! Looks like a good design and better offsets. Any word on pricing yet?

Pricing can be found here:
http://www.1addicts.com/forums/showthread.php?t=270937

[BrokenVert]

Nice job with the offsets, but common. Another set of CSL style wheels? Why can't a manufacturer make a nice set of DTM styles in 1 series offsets.

[larryn]

Originally Posted by BrokenVert

Nice job with the offsets, but common. Another set of CSL style wheels? Why can't a manufacturer make a nice set of DTM styles in 1 series offsets.

Kind of agree, but there are a bunch of CSL styles that almost fit, but have tire limitations (rubbing or severely limiting tire width) . These ones are taking into account the entire wheel tub. That makes them totally unique. Nobody is doing offsets like this, especially in a lightweight wheel. You'll be getting much more rubber, and probably losing 10lbs a corner of unsprung weight, by replacing the 29lb stocker wheels.

Also, it's not a curving spoke design, like every other CSL rep out there. The mounting plate is recessing in a cup-like design. It definitely reminds me of the Kosei K1's mounting plate area, where the spokes attach from the tire bead lip area to the rim of a cup, and the bottom of the cup is the mounting plate.

[BrokenVert]

Yeah I guess so. I was just hoping that since they were already spending the money for new equipment that they would come up with a more unique spoke design you know?

Ohh well, I guess thats a pipe dream. Its time to write a bunch of letters to OZ I guess.

Originally Posted by larryn

Kind of agree, but there are a bunch of CSL styles that almost fit, but have tire limitations (rubbing or severely limiting tire width) . These ones are taking into account the entire wheel tub. That makes them totally unique. Nobody is doing offsets like this, especially in a lightweight wheel. You'll be getting much more rubber, and probably losing 10lbs a corner of unsprung weight, by replacing the 29lb stocker wheels.

Also, it's not a curving spoke design, like every other CSL rep out there. The mounting plate is recessing in a cup-like design. It definitely reminds me of the Kosei K1's mounting plate area, where the spokes attach from the tire bead lip area to the rim of a cup, and the bottom of the cup is the mounting plate.

[Eddy@ApexWheels]

Yes they are a mesh design wheel, but they are VERY different from CSL style wheels as Larry pointed out. The center area and the spoke angle are the biggest aesthetic differentiator.

The most important thing to note is that there are NO CSL style wheels out there that are light. They are all cheap cast wheels for show only. These ARC-8 wheels are semi forged so you're cutting about 6lbs. of weight off of even the CSL reps. And most of this weight is from the barrel which effects rotational inertia the most. So even if they were the same weight, they would behave like a lighter wheel under acceleration and braking. Over all for track use these are more practical. CSL wheels don't have an open center area, they have recessed lugs. Besides the metal/weight savings, you have fast easy access to all your lugs with room for a heavy duty impact socket without scraping the paint off your wheels.

Why are they this design? Because this is what we were already producing in 7+ other fitments and only the rear is custom for the 1 series. The fronts already exist, so we don't have to reinvent the wheel there. It's the easiest way of handling the unique fitment. Pricing would double if both front and rear were created from scratch for this fitment.

ARC-8 wheel


CSL wheel

[BrokenVert]

Thanks for the correction...but I still don't like the way they look.

Originally Posted by paintpro21

Yes they are a mesh design wheel, but they are VERY different from CSL style wheels as Larry pointed out. The center area and the spoke angle are the biggest aesthetic differentiator.

The most important thing to note is that there are NO CSL style wheels out there that are light. They are all cheap cast wheels for show only. These ARC-8 wheels are semi forged so you're cutting about 6lbs. of weight off of even the CSL reps. And most of this weight is from the barrel which effects rotational inertia the most. So even if they were the same weight, they would behave like a lighter wheel under acceleration and braking. Over all for track use these are more practical. CSL wheels don't have an open center area, they have recessed lugs. Besides the metal/weight savings, you have fast easy access to all your lugs with room for a heavy duty impact socket without scraping the paint off your wheels.

Why are they this design? Because this is what we were already producing in 7+ other fitments and only the rear is custom for the 1 series. The fronts already exist, so we don't have to reinvent the wheel there. It's the easiest way of handling the unique fitment. Pricing would double if both front and rear were created from scratch for this fitment.

ARC-8 wheel


CSL wheel

[trboboost91]

any plans for a 17"??

sorry to ask but i forgot.
what are the stock offsets again?

[crex]

Originally Posted by trboboost91

any plans for a 17"??

sorry to ask but i forgot.
what are the stock offsets again?

Yes any plans for 17"?

49 and 52 for the 18"

However the front tire has a width of 7.5" and the rear is 8.5"

[larryn]

Originally Posted by crex

Yes any plans for 17"?

49 and 52 for the 18"

However the front tire has a width of 7.5" and the rear is 8.5"

Correct! Here's a little more detail:

18 x 8.5 et52 - rear
18 x 7.5 et49 - front

Tires are:
245/35/18 - rear
215/40/18 - front

[dyong]

Originally Posted by BrokenVert

Thanks for the correction...but I still don't like the way they look.

Agree. The design has no concavity like the CSL. For me too big a wheel = more road friction => less fuel efficiency and poorer performance. Unless you track the car and up the engine performance > 500hp++, otherwise for a street car it serves no purpose.

[larryn]

Originally Posted by dyong

Agree. The design has no concavity like the CSL. For me too big a wheel = more road friction => less fuel efficiency and poorer performance. Unless you track the car and up the engine performance > 500hp++, otherwise for a street car it serves no purpose.

Gonna have to greatly disagree here. Lowering your unsprung weight actually greatly increases performance by a lot, and lowers gas consumption, as there is less weight to get rolling. 19lbs spun forged wheels compared to 24lb cast alu CSL reps.. there will be decent seat-of-the-pants throttle response benefits, and if driven normally, will sip less gas.

Also, finally having the ability to run tires with the only limitation of wheel wheel, instead of the fender is HUGE to a lot of people.

Lastly, lighter weight wheels make more of a noticeable difference on less HP cars, not more HP cars.

I think these wheels serve enormous purpose... There's nothing like them in existence (fitment and weight wise).

Looks are subjective... I like 'em, perfectly fine with others not liking the looks of them.

[crex]

Originally Posted by larryn

Gonna have to greatly disagree here. Lowering your unsprung weight actually greatly increases performance by a lot, and lowers gas consumption, as there is less weight to get rolling. 19lbs spun forged wheels compared to 24lb cast alu CSL reps.. there will be decent seat-of-the-pants throttle response benefits, and if driven normally, will sip less gas.

Also, finally having the ability to run tires with the only limitation of wheel wheel, instead of the fender is HUGE to a lot of people.

Lastly, lighter weight wheels make more of a noticeable difference on less HP cars, not more HP cars.

I think these wheels serve enormous purpose... There's nothing like them in existence (fitment and weight wise).

Looks are subjective... I like 'em, perfectly fine with others not liking the looks of them.

will the front wheel stick out of the fender or rub.. with stock suspension or bmw performance suspension?

[Eddy@ApexWheels]

Originally Posted by dyong

Agree. The design has no concavity like the CSL. For me too big a wheel = more road friction => less fuel efficiency and poorer performance. Unless you track the car and up the engine performance > 500hp++, otherwise for a street car it serves no purpose.

you CAN NOT have a concave wheel on a 1 series if it's produced at the proper offset in a wide wheel design. and these wheels DO have concavity to them. of about 1-1.5". You will never see the same concavity that you do on an 18x10" M3 wheel with a Low offset. Look at the drawings above, and you will see there is no place for the spokes to go. The spokes are straight but very much NOT flat. The narrower CSL wheels are actually CONVEX at first, and then bow in around the hub area.

These ARC-8 wheels are 18". The 18" wheels that come stock with the 1 series are extremely heavy. I'm not sure what you're basing your road friction figures off of. These ARC-8 wheels are significantly lighter then stock. It can be measured in either improved full efficiency, greater acceleration, or shorter braking times depending on how you drive. You need less HP to turn a lighter wheel. This is why people buy lighter wheels. If your car weights less, it takes more HP for it to accelerate. Removing unsprung weight (wheels/tires/brakes) effects the car 6-10 times more then chassis weight.

I believe you are under the assumption that your stock wheel/tire package is lighter then what these wheels with tires would be. Which is incorrect. Even if you have 17" wheels/tire. These are still lighter, and would be a weight saving improvement.

Originally Posted by trboboost91

any plans for a 17"??

The wheels already exist in a 17x9" et42 design. And 17x8.5" et40 are on the way. It's aggressive but a few people are running that 9" setup on the 1 series for autocross and track applications.

[dyong]

I am not saying about weight of the wheels. I totally agree that the lighter the wheel the better obviously. What I am meant was a too wide wheel will make the car stick to the road more and it takes more power to propel the car. Imagine two bicycles, one racing and another mountain bike. One has very thin tires and the other wide ones. It is obvious it is hard to peddle the mountain with the wider tires.

There has to be a balance. An all out wide tire does not necessary mean better performance.

[Eddy@ApexWheels]

Originally Posted by dyong

I am not saying about weight of the wheels. I totally agree that the lighter the wheel the better obviously. What I am meant was a too wide wheel will make the car stick to the road more and it takes more power to propel the car. Imagine two bicycles, one racing and another mountain bike. One has very thin tires and the other wide ones. It is obvious it is hard to peddle the mountain with the wider tires.

There has to be a balance. An all out wide tire does not necessary mean better performance.

This is also incorrect. The contact patch size that makes physical contact with the ground of a 205 width tire is the exact same as a 335. The shape is mearly different, and effects cornering forces. There is ZERO difference in road friction besides aerodynamic drag. You can look this up. There is absolutely no comparison of wide automotive wheels/tire to two very different types of bicycle tires with two very different types of tread shapes. It's funny you bring them up though because the off road tire/wheel is extremely heavy, which has a HUGE factor on how easily it spins. Not to mention the tires pressures are different which is the only factor besides a vehicle weight increase that can change the contact patch size.

Please DO NOT turn this thread into a discussion of wide vs. narrow wheels. Nobody looking for these wheels will agree with the concept of a narrower wheel providing any benefit besides less aerodynamic drag.

This is a technical thread about a specific set of wheels that people have wanted for track/racing reasons for a year now. All of the information you've brought up in this thread has been incorrect. And it is very clear you do not know what you are talking about. This is entirely the wrong place to get educated on this subject. If you would like to start another thread in the general section bringing up these questions, I would be more then happy discuss the topic there.

I found this link which should provide you with all the information you'd need on the subject http://www.carbibles.com/tyre_bible_pg2.html contact patch size is discussed half way down.

[Eddy@ApexWheels]

We're trying to get a feel for what colors people would be interested in. Custom one off colors can't be done, so final color selection would be based on a general consensus. Feel free to post colors you'd like to see.

Hyper Silver, Hyper Black. We're not sure if more people would rather have a gloss black or a matte black. We're open on the other colors.

[fourtailpipes]

is "hyper silver" like oem wheel silver? thats really the color i'd be most interested in.

please ignore the people complaining about the lack of concavity or whining about the looks. they dont understand the relationship between offset and concavity, and likely won't spend the time to learn why this is a conflict. they can buy CSL wheels and put narrow tires on them.

you're on deck to be the first to produce a performance wheel that actually fits well. i dont care if they're 3" conVEX as long as they allow me to put a tire where it belongs, not outside the fender! lets get this show on the road!

[Eddy@ApexWheels]

Hyper Silver is similar to the higher quality oem silvers out there. It's very liquid and bright. You can't see any metallic flake in it.

Thanks for the support.

Originally Posted by fourtailpipes

is "hyper silver" like oem wheel silver? thats really the color i'd be most interested in.

please ignore the people complaining about the lack of concavity or whining about the looks. they dont understand the relationship between offset and concavity, and likely won't spend the time to learn why this is a conflict. they can buy CSL wheels and put narrow tires on them.

you're on deck to be the first to produce a performance wheel that actually fits well. i dont care if they're 3" conVEX as long as they allow me to put a tire where it belongs, not outside the fender! lets get this show on the road!

[WAY]

To be quite honest I will live with whatever colour you end up producing, but if I have my way, bronze/gold would be the colour I go for as they trend is to have those colours. Anthracite is always good also.

[Eddy@ApexWheels]

Here's a really low quality grainy image from the factory of a 4x100 anthracite wheel. I should have the wheel in hand later this week and will take actual photos of the thing, and not these cell phone style pics

[BerkTechnology]

Originally Posted by paintpro21

Here's a really low quality grainy image from the factory of a 4x100 anthracite wheel. I should have the wheel in hand later this week and will take actual photos of the thing, and not these cell phone style pics

Looks GREAT! Can't wait to get these on our car!