The Peugeot SX is a motorcycle that Peugeot produced in the 1970s and 1980s. It was made in two engine sizes, the SX5 of 50 cc and the SX8 of 80 cc, and in both road and trail form.
Peugeot SX at a glance
| Type | motorcycle / moped |
|---|---|
| Period | 1970s and 1980s |
| Models | SX5 (50 cc) and SX8 (80 cc) |
| Versions | road, trail and cross or military |
| SX5 launched | 1975 |
| SX5 engine | 49.9 cc two-stroke, 38 × 44 mm, 2 hp at 5,300 rpm |
| SX5 gearbox | five-speed foot change with inverted controls |
| SX5 top speed | 45 km/h by construction |
| SX8 launched | 1978 |
| SX8 engine | 79.6 cc, 48 mm bore, 6 hp at 6,500 rpm |
| SX8 top speed | 75 km/h |
based on one source; no free photographs of the model were found, the existing thumbnail stays
History of the Peugeot SX
SX5
The SX5 of 50 cc went on sale in 1975 as the successor to the Peugeot Rallye. It had a five-speed foot gearbox with inverted controls and was fitted with pedals to comply with the moped law in France of the time; models without pedals were made for export only. The engine was a 49.9 cc two-stroke with piston-skirt admission, 38 by 44 mm, producing 2 hp at 5,300 rpm, and the top speed was limited by construction to 45 km/h so that it could be ridden from the age of 14 without a licence.
Kits from Autisa and Gilardoni took the capacity to 77 cc by fitting a 47 mm piston instead of the original 38 mm, and with a 19 or 21 mm carburettor and an expansion chamber the machine could reach speeds similar to its bigger sister, the SX8. It was not a success, because of its high price and a design already out of date: its piston-skirt admission was old-fashioned at a time when most mopeds, including the 103 that had been built since 1971, used reed valves. The SX5 was finally killed off in 1980 when manual gearboxes were banned on mopeds, which makes it rare and popular with collectors.
SX8
The SX8 of 80 cc went on sale in 1978 and used much of the mechanical layout and frame of the SX5. It kept the lower crankcase with the same 44 mm stroke but had a 48 mm bore and larger crankcases to take the new top end. The contact-breaker ignition, known to be fragile because of its internal high-tension coil, gave way to a Morel CDI electronic system, the transmission was lengthened and the number of clutch plates rose from three to five. The two-stroke engine, still with piston-skirt admission and 79.6 cc, produced 6 hp at 6,500 rpm and gave a top speed of 75 km/h, the limit that allowed riding from 16 with an A1 licence under the rules of the time.
The SX8 was not a great success with the general public, but it served with the French armed forces until it was replaced by the Cagiva A8 of 125 cc in the mid-1990s. There were road and trail versions of both models, and for the SX5 a cross version, the SX5 C.
Design and features
- Manual gearbox on a moped: five foot-operated speeds with inverted controls.
- Pedals: fitted to satisfy the French moped law of the time.
- Tuning kits: Autisa and Gilardoni took the 50 to 77 cc.
- SX8 improvements: CDI ignition and five clutch plates.
- Military service: the SX8 served with the French armed forces.
Peugeot SX versions
- SX5 (1975): road version of the 50 cc.
- SX5 T and SX5 C: trail and cross versions.
- SX8 (1978): road version of the 80 cc.
- SX8 T and SX8 AR: trail and military versions.
The SX5 followed the Peugeot Rallye and sat alongside the 103 in the range, although the two used very different engines. More in the Peugeot collection.
Sources
- Peugeot SX, French Wikipedia: SX5 and SX8 history, engines, gearbox, ban, military use
