1971 Red CT-90 K3
These pictures show a good example of the 1971 K3. Most of the differences between this and the K2 are cosmetic, for instance, the stripe logo over the frame cover. This bike also features mudflaps front and rear, which aren't common on any model and which tended to tear off in use. Few existing bikes have them, but there are often scraps left hanging and/or rivet holes for them. Notice the chrome strip around the bottom edge of the seat cushion. If you look carefully, you'll notice rubber plugs for rear turn signals. These were optional until 1973 (when they became standard) and are very rare on these bikes.