Jetting CR125 Shifter Kart

Jetting CR125 Shifter Kart

Stock & Mod Moto, PWK/PWM 38

23 ratings
7 reviews
$7.99

Details

Released
March 9, 2014
Updated
October 12, 2026

Features

Jetting CR125 Shifter Kart screenshot #1 for iPhone
Jetting CR125 Shifter Kart screenshot #2 for iPhone
Jetting CR125 Shifter Kart screenshot #3 for iPhone
Jetting CR125 Shifter Kart screenshot #4 for iPhone
Jetting CR125 Shifter Kart screenshot #5 for iPhone
Jetting CR125 Shifter Kart screenshot #6 for iPhone
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About

Get precise jetting recommendations for shifter karts with Honda CR125 engines. The app uses local weather data or manual input to calculate optimal settings for main jet, needle, and pilot jet. Fine-tune adjustments are stored for future use.

✓Jetting recommendations for Honda CR125 engines
✓Automatic weather data retrieval
✓Manual weather data input
✓Engine and track configuration settings
✓Fine-tuning adjustments for circuits
✓Support for multiple measurement units
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What's New in Jetting CR125 Shifter Kart

2.1

October 12, 2026

Version 2.1 • Apple Watch, widgets and Live Activity: your main jet for right now on your wrist, on the lock screen and in the Dynamic Island throughout your track day. • Track mode: your jetting large and high contrast, to read it in full sun with your helmet on. And dark mode throughout. • Alerts when the weather changes enough to change the main jet: "Air density has dropped by 1.8% since your last calculation". • Fuel: 98 E5, E10, E15, ethanol-free, CIK-FIA or race fuel, and the jetting is corrected for it. • Carburetor icing warning, using the criterion of civil aviation. • Fuel and oil mix calculator. • When you fetch the weather, the app detects the track you are at. 144 tracks in 22 countries. • Logbook synced through iCloud, and your jetting shared with your mechanic as a link or a QR code. • Fine tuning changes the jetting again, and the pilot jet is chosen from the sizes Keihin sells. • Location also works on iPad without GPS and indoors. • Report a problem and rate the app, from Results and from Help. IN EARLIER VERSIONS • 2.0: run logbook with ratings for low, mid and high, laps and RPM; tracks with the altitude of the track itself, the US ones first; the weather station and the values you type in on a single screen; the app full screen on modern iPhones.

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User reviews

Modified in Colorado

It seems to be a bit conservative but Great ap to have for a safe starting point.

Response from developer

Sorry for the very late reply, and thank you. A safe starting point is exactly the idea. Version 2.0, released in August 2026, adds a logbook where you note what you actually fitted and how it went, separately in low, mid and high, so you can see where your own engine ends up. We've changed how we look after reviews and emails, and from now on every one gets a reply.

Shifter racer

Good basis app for starting points on jetting. All jetting is unique to conditions engines and areas but this app is very useful.

Response from developer

Sorry it took us so long to reply, and thanks. Agreed: every engine and track is different. Version 2.0, released in August 2026, brings 143 preloaded tracks that set the track's own altitude, the weather station and manual values on a single Conditions screen, and a logbook for what you fitted. We've changed how we handle feedback, so every review and email now gets an answer.

Very Good Pp

Gives good directional information. My motors run leaner than the recommendations in the app, but the changes driven by atmospheric conditions are very good.

Response from developer

Sorry for the late reply, and thank you for the detail. We can't tell you that version 2.0, released in August 2026, changes this: its improvements are elsewhere. One of them is a logbook to record what you actually fitted and how it went in low, mid and high, with CSV export, which makes your own offset easy to keep. We've noted it; if you send your engine and setup to mobile@isenet.es, we'll look into it. We've changed how we handle emails and reviews, and all of them now get an answer.

Ignore my previous negative review

Ignore the negative review. I see what he's doing. It's the corrected altitude which is what is used for jettting anyway. Will test and see how it works.

Response from developer

Sorry for taking so long to reply, and thanks for giving it a second look. You're right: it's the corrected altitude that matters for jetting. Version 2.0, released in August 2026, adds 143 preloaded tracks, and choosing yours fills in the altitude of the track, not the town. We've changed how we deal with reviews and emails, and every one now gets a reply.

Best jetting app

I've been using this app for a couple of months now. I tested it out at Phoenix and El Paso, TX. So far, the jetting parameters are spot on. They tend to run on the rich side, which is always ideal for these expensive engines. I do run them at 1.5 richer just to be on the safe side as competition is more about the driver not the engine out here in El Paso with the Border Karting Association
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Response from developer

Thank you, and sorry for replying so late. Glad it's working in Phoenix and El Paso. Version 2.0, released in August 2026, adds a logbook where you can note the richer setup you actually run and how it went, plus 143 preloaded tracks with their altitude, US tracks first. We've changed how we handle reviews and emails, so every one now gets an answer.

Developer apps

FAQ

What is Jetting CR125 Shifter Kart used for?

Jetting CR125 Shifter Kart provides jetting recommendations for Stock Moto / Mod Moto shifter karts with Honda CR125 engines. It calculates optimal main jet, needle, and pilot jet settings based on current weather conditions and engine configuration.

How does Jetting CR125 Shifter Kart get weather data?

The app can automatically obtain weather data (temperature, pressure, humidity) from the nearest weather station using your device's location services and internet connection. Alternatively, you can manually input these values.

Can I customize jetting settings in Jetting CR125 Shifter Kart?

Yes, the app allows for fine-tuning adjustments to the main, needle, and pilot circuits. These customized values are stored for future sessions, helping you adapt to your specific engine and track.

What engine and track configurations can Jetting CR125 Shifter Kart handle?

Jetting CR125 Shifter Kart supports Stock Moto and Mod Moto classes, various air filter types, fuel feed systems, oil mix ratios, and circuit types (spring or road racing, short or long).

Does Jetting CR125 Shifter Kart support different measurement units?

Yes, the application supports multiple measurement units for temperature (°C, °F), altitude (meters, feet), and pressure (mb, hPa, mmHg, inHg, atm) to accommodate users worldwide.

What is the price of Jetting CR125 Shifter Kart?

Jetting CR125 Shifter Kart is a paid application priced at $7.99.

How often is Jetting CR125 Shifter Kart updated?

The app was last updated on October 17, 2023, with version 1.5. This indicates a history of maintenance and potential improvements.

What devices is Jetting CR125 Shifter Kart compatible with?

Jetting CR125 Shifter Kart is available for iPhone, iPad, and iPod devices, and has an age rating of 4+.