Yamaha VMAX-Venture 600 Idle Speed Adjustment
Idle speed adjustment alters engine speed to run slowly or faster while out of gear or disconnected from a load. To alter idle speed, turn the throttle stop screw, located on the carburetor, in or out to achieve the desired result.
A Yamaha 600 Venture or VMAX snowmobile engine only runs as well as it is tuned. A good carburetor tune can improve engine performance and fuel economy. A mistuned carburetor can literally damage an engine.
We all know a carburetor is a device on an internal combustion engine for mixing a fine spray of fuel with air. But do you know how to adjust idle speed on your sled? Use these engine idle speed adjustment procedures if you plan on adjust idle speed on your Yamaha VMAX/Venture 600.
Engine idle speed adjustment
Adjustment steps:
- Start up the engine and allow it to reach normal operating temperature (3 min.)
Throttle stop screw - Turn the throttle stop screw [1] in to increase idle speed or out to decrease idle speed until the factory specified engine idle speed is obtained.
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Factory recommended engine idle speed: |
NOTE: When you make minor changes to the motor idle speed, the throttle cable free play should also be adjusted.
Carburetor specifications
| Type | TM31 |
| Manufacturer | MIKUNI |
| I.D. Mark | 8DG100 |
| Main jet (M.J.) | #1:136.3, #2, #3 3:133.8 |
| Pilot jet (P.J.) | #42.5 |
| Pilot screw (P.S.) | 2 turns out |
| Float height | 11.3 ~ 15.3 mm (0.44 ~ 0.60 in) |
| Idle speed | 1,600 ± 100 r/min |
Refer to the download Venture 600 repair manual for additional carburetor tuning information. The manual covers mid-range and high-speed tuning, high altitude tuning, low speed tuning and pilot mixture screw adjustment service procedures.
Idle adjustment applies to the following models
| 1999 VT600C Venture 600 | 2000 VT600D Venture 600 | 2001 VT600F Venture 600 |
| 1999 VX600SXBC VMAX 600 SX | 1999 VX600ERC VMAX 600 Deluxe | 2000 VX600DXD VMAX 600 Deluxe |
| 2001 VX600DXF VMAX 600 Deluxe | – | – |
