The Jelcz M11 was a Polish high-floor city bus built by the Jelczańskie Zakłady Samochodowe in Jelcz-Laskowice. It combined the modified body of the Jelcz PR110 with the Csepel chassis and drivetrain of the Hungarian Ikarus 260 and was produced from 1984 to 1990.
Jelcz M11 at a glance
| Maker | Jelczańskie Zakłady Samochodowe, Jelcz |
|---|---|
| Type | high-floor city bus |
| Production | 1984-1990, usually dated 1985-1990 |
| First prototype | 1983 |
| Body | modified Jelcz PR110 |
| Chassis | Csepel 260.88 or 260.98 |
| Engine | RABA-MAN D2156HM6U, 10,350 cm³, 192 hp |
| Top speed | 82 km/h |
| Gearbox | Csepel ASH 75.2, five-speed |
| Rear axle | Raba 118 |
| Suspension | air, two front and four rear air springs |
| Built | about 2,600 |
The English Wikipedia gives 1985-1990 for the model, while the Polish article states that series production began in 1984; this page uses the Polish dates and notes the difference.
History of the Jelcz M11
The M11 was born of a currency crisis. In the early 1980s the Polish People’s Republic lacked foreign currency for the parts of the PR110, and by early 1984 the imported components for one bus cost 2,000 US dollars, while the WSK Mielec engine plant could build no more than 1,000 engines a year. A trade agreement signed in Warsaw on 24 October 1983 brought Hungarian Ikarus 260 buses and Csepel 260.88 chassis to Poland in exchange for Polish Fiat 125p and 126p cars and Star trucks, with about 1,500 complete chassis to be delivered between 1986 and 1990. The Jelcz M11, initially named M110, was meant as a stopgap that would end with the arrival of the all-Polish Jelcz M120, and the reliability problems of the M11 only accelerated work on that model.
The first prototype was completed in 1983, and during tests in Budapest engineers of the local polytechnic carried out computer-based endurance tests of the structural elements. Series production started in 1984 and ran alongside the PR110 and, until 1986, the Jelcz 043, ending in 1990 with about 2,600 buses built. The M11 went to most Polish operators except Warsaw, and could also be found with PKS regional operators such as those in Kłodzko and Kamienna Góra; it reached Warsaw in the 1990s, mainly with private operators, and used examples were exported to Russia in the same decade.
The Csepel chassis gave the bus a high, flat floor, and although it was responsible for most of the M11’s defects it also allowed engine parts to be shared with the Ikarus 260 and 280. The engine was the six-cylinder RABA-MAN D2156HM6U of 10,350 cm³ and 192 hp, mounted horizontally in the middle of the floor and giving a top speed of 82 km/h, below that of the Ikarus 260. A five-speed Csepel ASH 75.2 gearbox drove the rear axle through a propshaft made at Gewes in East Germany, and the Raba 118 rear axle was an upgrade on the unit used in the Ikarus 260. Steering came from a Csepel-Bendiberica column and a LiAZ A4 front axle, suspension was pneumatic with two air springs at the front and four at the rear, fed by a Csonka or Knorr compressor, and the drum brakes of 420 mm diameter worked in a Knorr air system. Apart from body details, including front and rear walls from the 120M fitted at Solec Kujawski and Kapena, and rare swaps to Raba D10UTS engines, the design changed little in six years.
Design and features
- Mixed design: a modified PR110 body on a Csepel 260.88 chassis shared with the Ikarus 260.
- Horizontal engine: the RABA-MAN D2156HM6U of 10,350 cm³ and 192 hp under the floor.
- Air suspension: two air springs at the front and four at the rear, with Knorr brakes.
- Stopgap that lasted: about 2,600 buses built between 1984 and 1990.
Jelcz M11 versions
- Jelcz M11: the standard city bus with the Csepel 260.88 or 260.98 chassis.
- Modernised buses: examples rebuilt with the front and rear walls of the Jelcz 120M and, rarely, Raba D10UTS engines.
The M11 used the body of the Jelcz PR110 and was meant to be replaced by the Jelcz 120M. More buses are in the Jelcz collection.
Video: Jelcz M11 #2608 [LS Socha Transport] 31.07.14 linia 103 + PRZEJAŻDŻKA
Video by david123lost on YouTube.
Sources
- Jelcz M11, English Wikipedia: origins, production, construction and drivetrain
- Jelcz M11, Polish Wikipedia: Hungarian agreement, service, modernisation and chassis details
