Rincon 650 fuel tune help spark plug condition check

[roughriderenegade]

I just pulled the spark plug from my 2003 Rincon 650 after giving the fuel system a good clean and swapping out the filter.

The bike fires up just fine, but I noticed it stumbles a little when it's warming up, like it might be running a bit lean. On the bright side, there's no hesitation when cruising at low speeds, so that's a relief!

What do you guys think about the condition of the plug? Does it sound normal to you, or should I be looking into adjusting the jetting?

 

[Brooklyn99]

Do you have any pictures just so I can be sure? Well if the plug is looking light gray and not crusty at all, you're probably just a bit lean on startup. You can try nudging the fuel screw out, see if that helps. Good luck!

 

[Buckles]

A slight stumble on warm-up is normal after cleaning, especially if the plug looks okay and cruising is smooth. If the plug shows a lean condition or it worsens, then consider adjusting the jetting

 

[horsep0wer]

A little stumble during warm-up can be normal,

A slight stumble on warm-up is normal after cleaning, especially if the plug looks okay and cruising is smooth. If the plug shows a lean condition or it worsens, then consider adjusting the jetting

Right, also especially after cleaning the fuel system, as the engine may run slightly lean until everything heats up and fuel flow stabilizes. If its smooth once cruising and theres no hesitation, the spark plug condition is likely fine and you probably dont need to adjust the jetting just yet, just keep an eye on it and check the plug color after a few rides to confirm it's burning properly.