We have developed a list of jetting specifications that we believe will help your bike run its very best. Please remember that sometimes the stock OEM jetting will work just fine, other times you may have to make an adjustment, so use our suggestions below as a guide to help with your jetting problem.
For two-stroke bikes, our jetting specs are for VP Racing C12 Racing Fuel at 0-1500 ft altitude, 70-85°F temperature, 32:1 pre-mix oil ratio. We recommend Maxima Castor 927 High Performance 2-Cycle Oil.
For four-stroke bikes, our jetting specs are for premium pump gas at 0-1500 ft altitude at 70-85°F temperature.
Please Note: The stock OEM jetting for your specific model is listed first, followed by our recommended jetting underneath that model.
| 1989 | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| Model | Main | Pilot | Needle | Pos | Screw | Power | Slide | Nozzle | Leak | Other |
| Honda | ||||||||||
| CR80R | ||||||||||
| Pro Circuit | 128 | 52 | STD | 2nd | 1.5 | |||||
| CR125R | ||||||||||
| Pro Circuit | 168 | 62 | STD | 2nd | 1 | |||||
| CR250R | ||||||||||
| Pro Circuit | 172 | STD | STD | 3rd | 1.5 | |||||
| CR500R | ||||||||||
| Pro Circuit | 172 | 52 | STD | 3rd | 1.5 | |||||
| Kawasaki | ||||||||||
| KX60 | ||||||||||
| Pro Circuit | 200 | 30 | STD | 2nd | 1.5 | |||||
| KX80 | ||||||||||
| Pro Circuit | 140 | 58 | STD | 2nd | 1 | |||||
| KX125 | ||||||||||
| Pro Circuit | 155 | 58 | STD | 3rd | 1.5 | |||||
| KX250 | ||||||||||
| Pro Circuit | 172 | 55 | STD | 2nd | 1.5 | |||||
| KX500 | ||||||||||
| Pro Circuit | 170 | 60 | STD | 3rd | 1.5 | |||||
| Yamaha | ||||||||||
| YZ125 | ||||||||||
| Pro Circuit | 290 | 22.5 | STD | 2nd | 1.25 | |||||
| Suzuki | ||||||||||
| RM125 | ||||||||||
| Pro Circuit | 360 | 60 | STD | 2nd | 1 | |||||
| 1988 | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| Model | Main | Pilot | Needle | Pos | Screw | Power | Slide | Nozzle | Leak | Other |
| Honda | ||||||||||
| CR125R | ||||||||||
| Pro Circuit | 165 | 60 | 1469 | 3rd | 1.5 | |||||
| CR250R | ||||||||||
| Pro Circuit | 175 | 62 | 1347 | 2nd | 1.5 | |||||
| CR500R | ||||||||||
| Pro Circuit | 168 | 58 | 1370 | 2nd | 1.75 | |||||
| Kawasaki | ||||||||||
| KX125 | ||||||||||
| Pro Circuit | 172 | 68 | 1368 | 3rd | 1.5 | |||||
| Suzuki | ||||||||||
| RM250 | ||||||||||
| Pro Circuit | 170 | 68 | 1368 | 3rd | 1.5 | |||||
| 1987 | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| Model | Main | Pilot | Needle | Pos | Screw | Power | Slide | Nozzle | Leak | Other |
| Honda | ||||||||||
| CR125R | ||||||||||
| Pro Circuit | 165 | 62 | 1468 | 3rd | 1 | |||||
| CR250R | ||||||||||
| Pro Circuit | 170 | 60 | 1368 | 2nd | 1.75 | |||||
| CR500R | ||||||||||
| Pro Circuit | 168 | 58 | 1370 | 2nd | 1.75 | |||||
| Suzuki | ||||||||||
| RM250 | ||||||||||
| Pro Circuit | 170 | 68 | 1368 | 3rd | 1.5 | |||||
| 1986 | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| Model | Main | Pilot | Needle | Pos | Screw | Power | Slide | Nozzle | Leak | Other |
| Honda | ||||||||||
| CR125R | ||||||||||
| Pro Circuit | 158 | 65 | 1470 | 3rd | 1 | |||||
| CR250R | ||||||||||
| Pro Circuit | 170 | 60 | 1368 | 3rd | 1.75 | |||||
| CR500R | ||||||||||
| Pro Circuit | 168 | 60 | 1372 | 3rd | 1.75 | |||||
| 1985 | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| Model | Main | Pilot | Needle | Pos | Screw | Power | Slide | Nozzle | Leak | Other |
| Honda | ||||||||||
| CR125R | ||||||||||
| Pro Circuit | 152 | 62 | 1472 | 3rd | 1 | |||||
| CR250R | ||||||||||
| Pro Circuit | 158 | 65 | 1368 | 3rd | 1.5 | |||||
| CR500R | ||||||||||
| Pro Circuit | 168 | 65 | 1370 | 3rd | 1.75 | |||||
| 1984 | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| Model | Main | Pilot | Needle | Pos | Screw | Power | Slide | Nozzle | Leak | Other |
| Honda | ||||||||||
| CR500R | ||||||||||
| Pro Circuit | 162 | 68 | 314 | 3rd | 1.5 | |||||
| ATV | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| Model | Year | Main | 2nd Main | Pilot | Needle | Pos | Screw | |||
| Honda | ||||||||||
| TRX250EX | 2001 | 122 | 38 | Stock | N/A | N/A | ||||
| Pro Circuit | 2001 | N/A | ||||||||
| TRX300EX | 1993-2007 | 122 | 38 | Stock | N/A | N/A | ||||
| Pro Circuit | 1993-2001 | N/A | N/A | N/A | N/A | N/A | ||||
| TRX400EX | 148 | 38 | Stock | |||||||
| Pro Circuit | 158 | 58 | Stock | Stock | ||||||
| Yamaha | ||||||||||
| 200 Blaster | 1988-2002 | 230 | 32.5 | Stock | ||||||
| Pro Circuit | 1988-2002 | 240 | 32.5 | Stock | Stock | |||||
| 350 Banshee | 1987-2002 | 200 | 25 | Stock | Stock | |||||
| Pro Circuit | 1987-2002 | 260 | 25 | Stock | Stock | |||||
| Mod Motor | 1987-2002 | Dyno Jet Kit | ||||||||
| Raptor 660 | 2001 | 140 | 145 | 22.5 | Stock | 1.5 | ||||
| Pro Circuit | 2001 | 145 | 150 | 22.5 | Stock | 2 | ||||
| Grizzly 650 | ||||||||||
| Pro Circuit | ||||||||||
| Suzuki | ||||||||||
| LTZ400 | N/A | |||||||||
| Pro Circuit | 160 | |||||||||
| Kawasaki | ||||||||||
| KFX400 | N/A | |||||||||
| Pro Circuit | 160 | |||||||||