How to Solve the Handlebar Vibration Issue of SYM FNX150?

[ColinFitz]

Troubleshooting tip: Eliminate the gap by adjusting the steering stem bearing nut. If the bearing nut is already tightened to the limit and the gap still persists, disassemble and inspect the ball bearings. Check whether the upper and lower bearing races are damaged. If damaged, replace with new ball bearings or upper/lower bearing races.

[ChloeRose]

Hey, I've been riding this bike for several years and when encountering handlebar wobble, you need to troubleshoot step by step. It's mostly caused by uneven tire pressure or worn wheel hub bearings. Start by checking the tire pressure yourself with a tool—the front and rear wheels should be balanced between 22-30 psi. If the issue persists, inspect the handlebar screws and suspension links for looseness, tighten them, and test again. Wobbling is more likely at high speeds, so gradually accelerating can help identify patterns. For prevention, I recommend checking tire pressure and suspension quarterly and avoiding prolonged high-speed riding to prevent component fatigue. If all else fails, don't force it—take it to a mechanic for a professional wheel balance adjustment, which usually costs a small amount. Don't overlook small details, like uneven roads amplifying wobble; maintaining smooth riding is key.