Ignition Condenser for vintage Honda CT90 - "Trail 90" motorcycles.
Ignition condensers are among the most failure-prone components of the ignition system. Even if your vintage Honda CT90 / Trail 90 appears to be in excellent condition, condensers degrade over time. Unlike most parts that wear out through movement, condensers don't physically move, but they endure heavy use as an essential part of the ignition system. The condenser helps prevent the contact points from wearing out and ensures that the ignition coil remains charged at high speeds. This, in turn, allows the spark plug to deliver a strong, consistent spark, igniting the air-fuel mixture efficiently.
A failing condenser may allow the motorcycle to idle properly but prevent it from revving high. Other signs of a faulty condenser include contact points that burn out too quickly, often requiring replacement after just a few hundred miles.
To diagnose a condenser issue, remove the points cover in a dark area and check for a bright spark or arc each time the points open. A small spark every few seconds is normal and acceptable. If your vintage Honda Trail 90 has been rewired by a previous owner, you may need to re-route the wires connected to the ignition coil. The condenser requires a solid ground contact with the frame, so be sure to clean the surface where the condenser is bolted on.
