4-100 Wheel Option Thread

[McFred]

This thread is to list/document Atom wheel options for the 4-100 bolt pattern. To contribute, please post your experiences and details on your setup. I started this thread in the US Ariel forum because the other versions of the Atom use a different bolt pattern. I have been researching this subject for a while and there are a variety of 4-100 wheel options out there but not a lot of info on what will fit the atom. There are also some conflicting reports on what will fit, and the central issue seems to be which brake package is installed. The lotus elise, older hondas, and miatas share the same bolt pattern so searching there has been the most productive. I was looking for an extra wheel package for track use, so I was mostly looking for 15" or a 15/16" combination and the hardest part is finding a wide wheel for the rear. It's also pretty hard to find details on combinations that other Atom owners are running. From what I've found good Atom wheel candidates include:

Team Dynamics
Rota slipstream
Volk TE37
Volk CE28N
SSR Type-C (spacers?)
949Racing 6UL (spacers on front)
ETHOS from Sector111
custom Keizer 3-peice

For bigger wheels like 17" and up there are a whole bunch of additional options. I really wanted to try the Hoosier 275/35R15 rear tire because I was consistently wearing out rears about twice as fast as fronts. The only wheels I could find wide enough for this were the 949 and the Keizer. The 949 wheels are cheaper than tires so I ended up buying a set to try. I was most worried about the rears fitting, but it ended up that the fronts needed a spacer so the spokes would clear the Wilwood 4-piston calipers. I have the camero calipers in the rear and they have plenty of room. 949 also makes a 15x10 wheel, but I think they might come close to hitting the lower A-arm on the back side (anyone tried them?). So here are 949 15x7 +4mm spacer and 15x9 with 205/50R15 and 275/35R15 Hoosier A6 on my Brammo Atom2:



(I posted a few more pics here: http://arielatomchat.com/forums/thread1162.html )

I *really* like this setup. It was worth at least 4 seconds back-to-back at motorsports ranch vs. R888 on Team Dynamics. Much lighter, tons of grip, less tail happy, shorter gearing, more even wear, etc. I think the next best setup would be 15x7 front and 16x8 rear which you can do with the Volk, Rota, or ETHOS wheels. Besides the Keizer/949 options, 16x8 is the widest wheel I could find without going custom or 17"+ on the rear. It does give you more tire options also, including the Dunlop Radical slicks which some atom owners have tried with success. I'm guessing the sizes used are 200/580R15 and 235/605R16 from looking here:

Tire Specs :: SascoSports

I think the car really should've come with the 15x7 16x8 combo, so I'm currently looking for a set of Volk CE28N to try.

I've noticed a distinct drop in collaboration on the forums, particularly in the more technical areas. I remember RandyLamp used to contribute all the time with his experiences, so this is my attempt to keep the ball rolling. If we can collect info here on what wheels work I think it would be pretty useful for other owners...

[Terry Kennedy]

This thread is to list/document Atom wheel options for the 4-100 bolt pattern. To contribute, please post your experiences and details on your setup. I started this thread in the US Ariel forum because the other versions of the Atom use a different bolt pattern.

To expand on this, this is for the Brammo Atom 2's, as I'm almost positive that the TMI Atoms use the UK pattern.

I have been researching this subject for a while and there are a variety of 4-100 wheel options out there but not a lot of info on what will fit the atom. There are also some conflicting reports on what will fit, and the central issue seems to be which brake package is installed.

There's also the "no 2 the same" issue with the Brammo cars. My car was built with 4-pot Alcons on the front and 2-pot Alcons on the rear (which was the top brake package at the time of my order) and the Team Dynamics Pro Race 1.2 wheels. Despite those wheels being used on later Brammo cars with 4-pot Alcons all around, I need spacers on my rear wheels to keep the wheels from hitting the calipers. This, despite several sets of uprights from Brammo, help and parts from TMI, and (finally) new uprights from Tom Smurzynski.

Team Dynamics

A brand, not a wheel model. Pro Race 1.2 in the Ariel-specified offset (F: +35/R: +38) should work. These are built-to-order with whatever offset is ordered. Neither the Pro Race 2.0 nor the Dymag wheels fit the Brammo cars with 4-pot Alcons without spacers.

Note that companies that make custom-size wheels for Atoms may decline your order, saying you have to go through the factory. It may be better to just give them the specs.

All of this assumes that you're running without fenders, or with wide adjustable fenders. If you need to make sure that things will fit inside the fender, something like a Percy's WheelRite may help. Don't rely on it completely - it won't tell you everything you need to know about caliper clearance, and can't match the profile of some tires you'd want to mount.

[Scuderia VA]

McFred,

Nice post. I have been looking for another set of wheels to use on the road.

Ideally, a set of DYMAGS... Anyone know of a set 15x7 / 16x8 for sale?

If not, I will purchase a set of TD Pro Race 1.2. Now that I've seen you post, a set of the Volk TE-37 would also be sweet. Has anyone had any luck with them on a Brammo with Alcon 4-piston on all four corners?

Terry,

While I'm certainly a newbie and have more to learn about these Atomic beasts ... I agree with your comment on "no 2 the same".

My late build Brammo is fitted with Dymags and no spacers on all four corners fitted with Alcon 4-piston brakes. Tires are Yokohama A048, 205/50/15(F)--- 225/45/16 (R).

For others reference, here's the page from the 2007 Owner's Manual.
Brammo Manual P24.jpg
Hope this helps.

Richard

[bolus]

Dymag went out of business if I remember correctly. Plus the cast magnesium is a bit more fragile. if you hit a curb you really should be getting them xray'd

[Scuderia VA]

Dymag went out of business if I remember correctly. Plus the cast magnesium is a bit more fragile. if you hit a curb you really should be getting them xray'd

Bolus,

I do remember seeing where they did go out of business but then also saw a few Dymag Carbon Fiber wheels for Porsches...

However... Yes. I'm familiar with the magnesium and its fragile state. That's actually why I want another set of wheels to use. This way I can keep the original Gold ones from the factory in MadMaxAtom ziplocs.

.

RP

[McFred]

Thanks for posting guys. The wide rears are the main part of the problem in my opinion, and you're right about the fenders. I have a pair of the wide fenders Bolus made, but I haven't made the brackets yet. The easy solution for now is to take them off. Anyway, I like the 15x7 16x8 combo because this basically sets you up for 205/50R15 245/45R16 tires, and there are a bunch of affordable sticky options out there in these sizes:

Toyo R888
Toyo RA1
BFGoodrich g-Force R1 (and R1-S compound)
Hankook Ventus Z214 (C51 and C71 compounds)
Kumho V710
Kumho V700
Hoosier A6
Hoosier R6
Dunlop Radical slicks

I don't have the alcon brakes or the TE37 wheels, but in my searches I've found:

fishkiller reported that 15x8 Volk TE37 wheels fit without spacers on his GiroDisc brake package on all 4 corners.

Mr. Woolery reported that a 16x7 +33 TE37 wheel fit on the front of the Atom with Alcons with about 3mm of clearance. He was going to test a 15" wheel but didn't say if it fit.

Kempo reported that 15x7 +28mm Volk CE28N fits over the Alcons, but I think he posted somewhere else that he had a spacer.

[McFred]

Bought some Volk CE28N wheels for the street and figured I'd post up results of the test-fit.
15x7 4x100 +28 ~9 lbs
16x8 4x100 +35 ~12 lbs

front

rear


Lots of room on the rear, still a bit up front for the 4-pot wilwoods.

[Dbwy]

Bought some Volk CE28N wheels for the street and figured I'd post up results of the test-fit.
15x7 4x100 +28 ~9 lbs
16x8 4x100 +35 ~12 lbs

front

rear


Lots of room on the rear, still a bit up front for the 4-pot wilwoods.

They look great! Can you post pics of the finished product when you get the tires installed?

[rijowysock]

Bought some Volk CE28N wheels for the street and figured I'd post up results of the test-fit.
15x7 4x100 +28 ~9 lbs
16x8 4x100 +35 ~12 lbs

front

rear


Lots of room on the rear, still a bit up front for the 4-pot wilwoods.

i had 2 sets 15/16 for my lotus exige and sold them SOOO cheap cause nobody wanted 15/16... wish i knew about the atom then.. would have kept.

debating ordering wheels now that i can share between atom and exige i might buy here soon.. there is no way the US atom's are UK spec hubs... would not make any sense and would be impossible to source parts.. ill ask monday but just common sense says they are 4x100... would just be silly otherwise... hubs, rotors, wheels,... just too laborious to drill otherwise.

[McFred]

I'll post up pictures when I get some tires.

Between 15s and 16 there seems to be a very large selection of tires both DOT and R-compounds. I think right now the 16x8's in the 8-spoke wheels are pretty hard to get a hold of. Huge lead-time if you buy them straight from Ray's.

I'm afraid Ariel does not feel compelled to abide by common sense... $5 says the AA3s are 95.25mm PCD and will remain that way. Personally, it seems very easy to fit the 4x95.25, 4x100 and 4x114.3 all on the same hub flange. But hey, that'd be common sense... :P