Why does the motorcycle's RPM not increase when accelerating?
2 Answers
Motorcycle's RPM not increasing when accelerating may be caused by blocked fuel line, throttle obstruction by foreign objects, wiring issues, or dirty throttle body. Blocked fuel line: Check if the fuel line is unobstructed, whether the fuel filter is clogged, the spark plug gap and carbon deposits, and the intensity of the high voltage from the ignition coil. If the voltage is weak, it may be due to a blocked fuel line. Throttle obstruction by foreign objects: After ignition, the idle speed may be higher when the engine is cold and normalize after warming up. If it's excessively high, first check if there's an issue with the throttle, such as obstruction by foreign objects. Wiring issues: If the speed doesn't increase when the throttle is fully pressed and the engine feels weak or sluggish, it might be due to engine damage. Dirty throttle body: It could be that the throttle body is dirty and needs cleaning.
My old motorcycle has recently experienced the issue of throttle sticking as well. From experience, clutch slippage is the most common culprit. Last time I opened it up and saw the clutch plates were worn shiny—when I pulled the clutch, the engine revved but the bike wouldn’t move. Another possibility is a clogged air filter or fuel pump not delivering enough fuel, making it feel like the throttle is being choked. A blocked exhaust is even worse—you can twist the throttle wide open and it still feels sluggish. If you’re DIY-inclined, check if the air filter box has water ingress or if the fuel lines are kinked. Replacing clutch plates isn’t expensive either; a roadside repair shop can do it for around 200 bucks. Whatever you do, don’t force it—breaking down mid-ride is way more troublesome.
