The 400 GTS is the bike with very similar to the 350 GTS aesthetics. The main novelties are the displacement, which is from 350 cc to 400 cc, and a front brake double standard disc, which allowed a greater stability and especially to be in step with the times.
The 1974 Moto Guzzi 350 GTS appearance was only the same as the Honda CB 350. Bore and stroke were 50 x 44 mm (Honda 47 x 50 mm). The design was completely new and there was to discover nothing that recalled the older models of Moto Guzzi. In 1974, the machine still had an old drum brake in the front wheel, but in 1974 it was replaced by a disc . The 350 GTS was produced in 1974 and 1975 and followed by the 400 GTS.