Why We Choose Isotropic Superfinishing

In racing, there's no room for "good enough." Every shift, every lap, every component is pushed to the limit. That's why at Kotouč Gearboxes,
Isotropic Superfinishing isn't an upgrade — it's standard. And there's a good reason for that.

LET'S BREAK IT DOWN. 

WHAT IS ISOTROPIC SUPERFINISHING?

Isotropic Superfinishing, also known as REM Superfinishing or ISF, is an advanced surface treatment process that creates an ultra-smooth, mirror-like finish on metal parts — especially gears, dog rings, shafts, and other high-contact components.
The term "isotropic" means uniform in all directions, and that's exactly what this process aims for: a surface finish that has no directional texture (unlike grinding or machining marks), which eliminates tiny peaks and valleys that normally cause friction and wear.

How it works - The process in detail

1. Initial Surface Preparation:

• Parts are first machined and heat-treated as normal.
• The process starts with a rough cut of the surface to expose all asperities (microscopic high points).

2. Chemically Accelerated Polishing:

• Components are then placed in a vibratory or centrifuge-style finishing drum, along with specially designed ceramic or plastic media and a chemical solution.
• The solution reacts with the surface of the metal to soften only the peaks, while the media gently wipes those peaks away.
• This is a non-directional, controlled removal process.

3. Self-Limiting Action:

• Unlike traditional grinding or polishing, this process stops when the high points are gone — leaving behind a smooth, uniform surface.
• It does not change part geometry or compromise tolerances. 

We’ve Been Doing This Longer Than Most

We started using REM Superfinishing long before it became popular in motorsport. While other companies were still figuring out what it was, we were already running it as part of our core production process.

Not as an upsell. Not as a gimmick. But as a way to make our gearboxes last longer, shift smoother, and take more punishment on the track.

That’s still how we do it today. 

Standard on Every Gearbox

For us, Superfinishing isn’t a special treatment. It’s part of the build — just like heat treatment or quality control. If a part needs it, it gets it.

This is one of the reasons our customers keep coming back:

• Less rebuilds mid-season
• Smoother gear engagement
• Less wear and tear on expensive parts
• Confidence lap after lap

WE DO IT IN HOUSE - AND FOR YOU

We don’t send parts out for finishing — we’ve got our own REM finishing drums and dryers right here at the factory. It means we can control every step of the process, and make sure it’s done right.

Better yet, we also offer Superfinishing as a service to our customers. Whether you’ve got a handful of parts or an entire batch, we can help. Especially if you’re working with hardened steel — it’s where this process really shines.

Want To Send Something In? 

Easy. Whether you're down the road or halfway around the world, we’ve got logistics covered.

Send your samples here:

Kotouč Gearboxes
Prerovska 561
75201 Kojetin
Czech Republic

Talk to Neal Mendham: +420 725 790 769
Worldwide pickup & shipping available

Superfinishing isn’t just about better surface finish. It’s about longer-lasting gearboxes, smoother races, and fewer surprises in the pits. And that’s why we build it into every gearbox that leaves our shop.

No upsell. No shortcuts. Just high-performance components — built the way they should be.

Want to learn more or book in your parts? Give us a shout. We’re ready when you are.