A Proven Combo: Kosei K1 Racing Wheels and Falken Azenis Tires | Garage Rescue Miata

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David S.
Update by David S. Wallens to the Mazda Miata project car
Jan 19, 2021

We’re putting the band back together. 

BSI Racing worked on our 1992 Miata back in the day, and that’s the shop going through the car as we get it back on the road after an eight-year slumber

Ed Senf tuned the Miata some 20 years ago. Let’s just say that we have been chatting lately. 

We used Moss Motors parts in the original build, and we’ve already placed recent orders with them. 

While our Miata has worn a few sets of wheels over the years, the run started with the Kosei K1 Racing—circa April 1999. This wheel was aimed right at our market.

First, there was the simple, effective profile. Nothing protruded past the lip, meaning rubbing doors wouldn’t send spokes knocking. The wheel also featured lots of room around the lugs—great for flying impact guns on pit road—while the open design promoted brake cooling. It worked without a center cap. 

The Kosei K1 Racing featured heat-treated, shot-peened construction, and a range of sizes and competitive pricing made it a popular sight. You saw this wheel on everything back then, and several GRM project cars wore it: our BMW M3, Honda Civic Si, Toyota Celica and more. 

Tire Rack still imports the model, with today’s K1 Racing available in silver or gloss black in 15- and 17-inch sizes—basically for BMWs as well as cars that use a 4x100 bolt pattern. Pricing starts at around $145 each, including the blue valve stems. 

In the 15x7-inch size, a few different Miata-friendly offsets are offered: 25mm, 30mm and 38mm.

We had to order a set. It was the car’s destiny. This time, though, we went with the gloss black. White, even if still available, would have been just a bit too ’90s for us. We ordered the 15x7-inch wheels with the 30mm offset. That allowed us to get the wheel in a hubcentric fit for the Miata, too. It would also widen the track a tick while still keeping us from needing to roll the fender lips. Bonus points, Tire Rack, for the double-boxing. 

We also ordered some lightweight lugs from Tire Rack. As it did back in the day, the Kosei K1 Racing offers a lotta room for an impact socket. 

Those 15x7-inch Kosei K1 Racing wheels are lighter than promised, too, checking in at 12 pounds, 13.60 ounces.  

But what to wrap around the wheels? Again, we looked to the car’s past. 

Two decades ago, the Miata also introduced us to another name: Falken. The Falken Azenis RT215 was new for 2001, and the Miata was wearing a set by March of that year. 

Our tire world looked different back then, with race-ready R-comps dominating the scene. However, the SCCA had just introduced a new autocross class that favored true street tires: Street Touring. (At the time, there was just a single Street Touring class; its mission was to welcome the day’s sport compact crowd.)

What tires were we to run if the rules forbade R-compounds? Everyone scrambled to find an answer, but these new Falkens quickly found favor thanks to their speed and good price.

The Falken Azenis model line has been part of our scene ever since—with upgrades over the years, of course. The latest iteration is the Azenis RT660, and it’s still a streetable model aimed at competition classes that require true 200-treadwear street tires. You can track it, autocross it, or just drive around on it. Today, though, there are just way more classes and programs that require and welcome true street tires. (Dive deeper with our latest test of the Falken Azenis RT660.)

So we ordered a set of the Falken Azenis RT660 in the ever-popular 205/50R15 size. Tire Rack stocks them at about $122 each, a very competitive price for that size and class. 

Like we said, we’re putting the band back together.


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DeadSkunk  (Warren)
DeadSkunk (Warren) PowerDork
1/15/21 7:45 a.m.

Sorry, but the white ones look better.

captdownshift (Forum Supporter)
captdownshift (Forum Supporter) GRM+ Memberand UltimaDork
1/15/21 7:56 a.m.

In reply to DeadSkunk (Warren) :

Keeping white wheels clean is no fun, Kosei needs to make them in bronze (not gold) 

Colin Wood
Colin Wood Associate Editor
1/15/21 8:08 a.m.

In reply to captdownshift (Forum Supporter) :

When I was younger, I used to be all about black wheels, but now that I'm slightly older, I've realized there is something cool about bronze wheels.

I second that white wheels are a pain to keep clean, but maybe that's where the appeal comes from. You see someone with white wheels, and you'll say to yourself "wow, that person spent a lot of time to keep those clean."

jimbob_racing Dork
1/15/21 8:22 a.m.

I had silver wheels like that on my red 93 miata. I loved how they looked and how easy it was to clean them with such large openings between the spokes.

David S. Wallens
David S. Wallens Editorial Director
1/15/21 8:25 a.m.
DeadSkunk (Warren) said:

Sorry, but the white ones look better.

Warren Martin,'99 Miata,'03 CooperS,'91 GTI 16V,06 Scion Xb ,73 Corolla SR5, 2019 GMC Canyon

It's funny, but there was some debate on color. The photo at the bottom--with the hood up--was taken about 30 seconds after I first saw the Miata on the black wheels. I admit, it took my breath away. The stance, the look, the whole thing. 

Put me down as a big, big fan of bronze/gold as well. 

engiekev HalfDork
1/15/21 11:19 a.m.

Kosei K1 are by far the coolest light wheels out there!  I have one set for my 1G DSM, and looking for another set for my NA Miata.  

If you need a center cap, look into a 3D printed one to save some money over the hard to find Kosei caps.  RaceTruckRon here helped with printing some in resin for me, and I could also print some up on high temp PLA or PETG.  They will need to be removed before track days, as would any center cap, due to the high heat.

David S. Wallens
David S. Wallens Editorial Director
1/15/21 11:26 a.m.

Glad to see another K1 fan out there. I was going through some old photos the the other night and came across this one.

Thanks for the tip re. 3D printed center caps, too. 

Olemiss540 Reader
1/15/21 11:29 a.m.

Why clean wheels when you can just plasti-dip them gunmetal?

Gunmetal/anthracite is just another color code for "brake dust".

David S. Wallens
David S. Wallens Editorial Director
1/15/21 11:37 a.m.

In reply to Olemiss540 :

Someone needs to make a wheel that comes in white, black and brake dust. 

engiekev HalfDork
1/15/21 12:01 p.m.
Olemiss540 said:

Why clean wheels when you can just plasti-dip them gunmetal?

Gunmetal/anthracite is just another color code for "brake dust".

Where can you order anthracite, other than dipyourcar? Actually their prices are pretty good.  We did our pathfinder in anthracite and they hold up excellent.


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