# Rotax MAX Jetting — Carburetor Mainjet Setup

> Calculates optimal carburetor main jet size for Rotax kart engines based on ambient conditions. (iPhone/iPad app by BRP-Rotax GmbH & Co KG.)

- Source: https://appshunter.io/ios/app/rotax-max-jetting/id1152315347 (this page in markdown: same URL + `.md`)
- Developer: [BRP-Rotax GmbH & Co KG](https://appshunter.io/developer/1152315346)
- Category: Sports, Utilities
- Price: Free
- Rating: 1.90/5 from 8 App Store ratings · 5 written reviews indexed
- Age rating: 4+
- Requires: iOS 17.0 · 13 MB
- Languages: American English, German (Germany)
- Released: 2016-09-17
- Data updated: 2026-08-31
- Monetization: free
- User reviews in markdown: https://appshunter.io/ios/app/rotax-max-jetting/id1152315347/reviews.md

## What is Rotax MAX Jetting?

The Rotax MAX Jetting App enables the user to calculate the optimal carburetor main jet size for Rotax kart engines of the MAX series:

- 125 Micro MAX evo
- 125 Mini MAX evo
- 125 Junior MAX evo
- 125 Senior MAX evo
- 125 MAX DD2

based on the current ambient conditions

- Temperature
- Altitude
- Air pressure 
- Humidity

This can be done either automatically using GPS and a functioning internet connection or manually by entering the ambient parameters.

*Automatically*

Click on Use GPS position for weather data, select the desired engine type from the scroll menu and start the calculation tabbing the Calculate button.

*Manually*

Enter all ambient parameters, select the desired engine type from the scroll menu and start the calculation tabbing the Calculate button.

Important: Since the calculation is based on the "relative air pressure" (air pressure at 0m above sea level), your own barometer must be calibrated to the current altitude before you can actually use the value. Online weather services provide this value by default.

To toggle between Celsius and Fahrenheit, press °C/°F and to choose between meters and feet press m/ft next to the entry of the value.

To start a new calculation, click Reset.

## Key features

- Optimal main jet calculation
- Supports multiple Rotax MAX engines
- Automatic GPS weather data
- Manual ambient parameter entry
- Celsius/Fahrenheit toggle
- Meters/Feet toggle

## Recent user reviews (5 of 5)

All indexed reviews: https://appshunter.io/ios/app/rotax-max-jetting/id1152315347/reviews.md

### 2/5 — What an app

*2023-01-09*

This is a fantastic app

But I have got one problem I keep 4 stroking and piling up at start of races. I’ve asked around the paddock and I’ve said I se the app (they told me I was to Rich)

So what I found out after a long expensive day of four stroking I was to Rich so what ever you do the best part of the app don’t press calculate

### 1/5 — Worked once….

*2022-07-21*

Got app to work once, now it doesn’t even display a jet size for Senior max. Just says 1…. Each time I try to use. Will display jet size for micro, mini and junior. DD2 is same, just 1…. You’d think Rotax would do a little better.

### 1/5 — Ne fonctionne pas

*2021-01-05*

App qui ne fonctionne pas sur mon iPhone SE première génération iOS 14.3

### 1/5 — Whoops

*2020-10-08*

All well and good until you press calculate and nothing !!!!!

Yet again a developer ‘improves ‘ without testing.

### 1/5 — Way too rich!

*2019-09-06*

This app recommends jet sizes much larger than my engine/carb. requires.

## Frequently asked questions about Rotax MAX Jetting

### What Rotax MAX engines does Rotax MAX Jetting support?

Rotax MAX Jetting supports the 125 Micro MAX evo, 125 Mini MAX evo, 125 Junior MAX evo, 125 Senior MAX evo, and 125 MAX DD2 engines.

### How does Rotax MAX Jetting calculate jetting settings?

It calculates settings based on ambient conditions such as temperature, altitude, air pressure, and humidity. This can be done automatically using GPS or manually by inputting the parameters.

### Can I use Rotax MAX Jetting without an internet connection?

Yes, you can manually enter ambient parameters if you do not have a functioning internet connection or GPS. The automatic calculation requires GPS and an internet connection for weather data.

### Does Rotax MAX Jetting have ads?

No, Rotax MAX Jetting does not contain advertisements.

### What is the rating for Rotax MAX Jetting?

Rotax MAX Jetting has a rating of 1.9 stars based on 8 user ratings.

### How often is Rotax MAX Jetting updated?

The latest version, 2.1.2, was last updated on February 16, 2026. The app was initially released on September 17, 2016.

### What devices is Rotax MAX Jetting available on?

Rotax MAX Jetting is available for iPhones and iPads.

### What is the age rating for Rotax MAX Jetting?

Rotax MAX Jetting has an age rating of 4+.

## Version history (last 5 releases)

### 2.1.4 — 2026-06-29

Improvements and bug fixes

### 2.1.3 — 2026-03-31

Improvements and bug fixes

### 2.1.2 — 2026-02-16

Improvements and bug fixes

### 2.1.1 — 2026-02-02

Improvements and bug fixes

### 2.1.0 — 2026-01-12

Never lose that perfect setup again!
You can now log in with your Rotax Connect account to save, track, and review all your past engine calculations.

## Apps similar to Rotax MAX Jetting

| App | Rating | Price | Category |
| --- | --- | --- | --- |
| [Jetting Rotax Max Kart](https://appshunter.io/ios/app/jetting-rotax-max-kart/id1453317954) | 4.9 (9) | $7.99 | Sports |
| [Jetting for TM KZ / ICC Kart](https://appshunter.io/ios/app/jetting-for-tm-kz-icc-kart/id1450856766) | 4.9 (11) | $14.99 | Sports |
| [Jetting Max Kart for Rotax Max](https://appshunter.io/ios/app/jetting-max-kart-for-rotax-max/id811255761) | — | $7.99 | Sports |
| [Jetting for IAME kart engines](https://appshunter.io/ios/app/jetting-for-iame-kart-engines/id1052571489) | — | $7.99 | Sports |
| [Jetting Rotax Max EVO Kart](https://appshunter.io/ios/app/jetting-rotax-max-evo-kart/id1451969138) | 4.9 (11) | $7.99 | Sports |
| [Jetting for DellOrto VHSB PRO](https://appshunter.io/ios/app/jetting-for-dellorto-vhsb-pro/id6477762438) | — | $9.99 | Sports |

## More apps by BRP-Rotax GmbH & Co KG

- [Rotax Global](https://appshunter.io/ios/app/rotax-global/id1298634783)
- [Rotax MAX Dome](https://appshunter.io/ios/app/rotax-max-dome/id1466602145)
- [Rotax 100+](https://appshunter.io/ios/app/rotax-100-plus/id1489298345)
- [Rotax TRAX: Kart & Race Coach](https://appshunter.io/ios/app/rotax-trax-kart-and-race-coach/id6444654157)
- [BRP-Rotax Now](https://appshunter.io/ios/app/brp-rotax-now/id6450586012)

All apps by BRP-Rotax GmbH & Co KG: https://appshunter.io/developer/1152315346

---

*Data collected daily from the US App Store and indexed by [AppsHunter](https://appshunter.io/). User reviews are verbatim App Store reviews. Ratings, prices and chart positions refresh continuously; this snapshot is from 2026-08-31.*