The CG125 has an extremely tough engine capable of thousands of trouble free miles. It’s important to keep good oil in the engine and no more. As they have a very simple motor, all you need is a very basic understanding of motorcycle mechanics to keep one on the road.
The most complex job is changing the points. The flywheel must be removed, either using the special tool or a cruder method. Simply slacken the nut, holding the flywheel by placing a strong screwdriver through it and between the coils (ahem - Ed). Wedge two chisels under the flywheel, being careful not to damage the coils. When there’s enough pressure on the flywheel, simply tap the slackened nut firmly and the flywheel jumps free.
Those who indulge in wheelies will find themselves with a wrecked crankshaft because the sudden forces on the transmission do nasty things to the flywheel which is only held on by friction - the soft woodruff key is only there to position the flywheel.
Good oil changed frequently will protect the small end, as there is no small end bearing between it and the gudgeon pin, once the small end wears the conrod is rapidly ruined. If the tappets sound loose but are adjusted correctly it’s probably the small end, as it sounds exactly the same when worn. All CG engines seem to use oil, I don’t know one that doesn’t.
The CG doesn’t handle at all well. All the design effort went into the pushrod single cylinder motor. Once the CG has done a few thousand miles the rear shocks are knackered. But even with decent shocks it’s still not a good handler, it just wasn’t designed for flying round corners well banked over. Treat it with respect and it'll get there eventually.
The CG also has a weak centre stand, never sit on the bike when it’s on this stand or it'll bend. Both the stand and the rear brake pedal rotate on a pin that needs to be removed and greased once a year. Fail to do this and the components will fuse together with rust and grit it'll take you lots of work with a large hammer, much swearing and a long weekend to fix it. By the way, when putting the bike on the stand use the hand rail provided, pulling on the seat will pull it off. The mirror fixes to the right hand throttle/switch assembly and if the bike falls over on this side it'll write off the whole assembly, which costs a mere thirty notes to replace.
Both mudguards like to rust. The front has a bracket under it that traps dirt, whilst the rear has a wire tunnel that does the same - underseal them and hope for the best. The lights are useful for day time riding, just enough to warn off car drivers without irritating them. At night, go faster than 40mph and things become dangerous.
Overall the CG125 is a useful commuter, with a reliable engine and a chassis that lacks a decent build quality.
S McGlinchey