KTM 85 Jetting
Since the KTM 85 SX, Husqvarna TC 85, and GasGas MC 85 share the same engine and Keihin PWK 28 carburetor (for models 2018–2025), the jetting recommendations are identical across all three brands.
Jetting is highly dependent on your altitude and air temperature. Below are the baseline "Factory" settings and the most common "Performance" tweaks used by race teams like Pro Circuit.
1. Baseline Factory Settings (Sea Level, 60°F–80°F)
These are the standard settings for a stock bike running a 40:1 or 50:1 fuel-to-oil ratio.
Main Jet: 142 or 145 (142 is most common for standard conditions)
Pilot Jet: 45 or 48
Needle: NRKC
Clip Position: 2nd or 3rd from the top
Air Screw: 1.5 to 2.0 turns out
Slide: 3.0
2. Pro Circuit "Race" Recommendations
For riders looking for crisper throttle response and better mid-range pull, Pro Circuit often recommends leaning out the bike slightly compared to the rich "safety" margin provided by the factory.
Main Jet: 142
Pilot Jet: 45
Needle: NRKC
Clip Position: 2nd from top
Air Screw: 1.75 turns out
3. Jetting Adjustment Guide (Weather & Altitude)
If your bike is "bogging" (too rich) or "pinging" (too lean), use this quick-reference guide to adjust:
| Condition | Adjustment Needed | Effect |
| Hot Weather / High Altitude | Go Leaner (Smaller Jets) | Air is less dense; you need less fuel. |
| Cold Weather / Sea Level | Go Richer (Larger Jets) | Air is dense; you need more fuel to prevent seizing. |
| Deep Sand / High Load | Go Richer | Keeps the engine cooler under extreme stress. |
Pro Tips for 85cc Jetting:
The "Bog" Test: If the bike bogs when you crack the throttle quickly, your Pilot Jet or Air Screw is likely too rich. Try turning the air screw out 0.25 turns at a time.
Fuel Quality: These high-performance 85s are sensitive to fuel. Always use 98 octane (or highest pump available) mixed with a high-quality synthetic oil like Motorex or Maxima.
JD Jetting Kit: If you want to take the guesswork out, many riders install a JD Jetting Kit. They provide custom multi-taper needles that drastically improve the "flat spots" in the stock 85cc powerband.