The Single Ports (pre 1975)


1964, CZ 250 ISDT

Just as CZ mx twin pipe's were developed from ISDT bikes, so were the mx single ports. Above is the CZ ridden by Joel Robert in the 1964 ISDT. The bike is basically his twin pipe moto-cross bike with a single exhaust port cylinder, a high pipe ran up the right side of the bike. This bike might be considered one of the first side-pipe CZ’s.

1966, Paul Friedrichs on CZ works side pipe

In 1966 East German Paul Friedrichs became the first CZ factory rider to campaign the single port CZ in the 500cc world championships. The side pipe was reportedly harder to ride than the twin pipe, but Friedrichs managed OK, winning the first GP of the season and going on to win the 1966 500cc world moto-cross championship. He won the title in 67 & 68 also.

Works 360 side pipe 1966

Works 250 single port 1967

1967, Joel Robert on the works CZ single port

Joel Robert waited until 1967 before racing a CZ single port in the GP’s. Unlike the 360 that Friedrichs raced, Robert’s 250 featured a low pipe. The frame was different also. The front down tube did not curve under the engine, making more room for the low pipe. Robert's factory bike also featured a red tank with chrome knee pads, strangely reminiscent of a Husqvarna tank. Robert and his CZ won the 250 World Championship in 1968 & 1969. He then switched to Suzuki in 1970.

1967, CZ 360 side pipe

It would seem that the 360 side pipe went into production while the 250 twin pipe was still being built. The 1967 brochure that the above picture came from still shows the 250 twin pipe, but the 360 is shown as a side pipe model with a chrome sided tank. It is not known if this chrome sided tank ever came on a production bike, but the tank is very similar to the tank used by Roger DeCoster in 1967 when the CZ team toured America racing the Inter-am series.

CZ 360 side-pipe

CZ 360 side pipe

1968-1970, CZ 360 side pipe

The above 1969 360 side pipe (type 969/01) is owned by Less Packer, of Wiltshire, England. 250 & 360 side pipes are hard to tell apart, most of the bikes produced had the orange paint scheme, but some yellow bikes did come off the assembly line. The CZ works bikes of this time period featured innovations like Femsa electronic ignitions and double cone expansion chambers like the one tried on Fredrichs bike in 1969.

1971-1972, CZ 380 yellow tank

Owner John Homan, Bend, Oregon. This yellow tanker was on display at the AHRMA national moto-cross at Eugene, Oregon in 1994. I think this is a 380, like the side pipes, the yellow tankers were hard to tell apart. The open class CZ’s went to 380cc with the introduction this model. In 1970, works CZ rider Paul Friedrichs started racing the yellow tank model, his bike featured a radial fin cylinder head and double stinger low pipe.

CZ 380 Yellow tank

CZ coffin tank

1973, CZ 250 coffin tank

Owner Clyde Williams, San Deigo. In 1973 CZ went to the steel version of the aluminum coffin tank that had been used on the works bikes in 1972. The 250’s had red tanks with the 380’s coming in blue. The 250’s also now had 5-speed transmissions. The 73 works CZ’s featured magnesium case, center port engines. The front down tube of these bikes split above the exhaust port to accommodate the center port engine.

1973, CZ 125 Moto-cross

Another one of Less Packer’s immaculate CZ’s. This is an excellent example of the 73 125 moto-cross. The 125 had actually been introduced in 71 with the yellow tank. The prototype 125 moto-cross had been developed in 1970, first using a CZ road bike based frame, wheels, and suspension units.

CZ 125 Moto-cross

CZ 250/380 Red Frame

1974, CZ 250 red frame

Owner Giorgio Invernizzi (Italy). The 74 CZ’s came with a redesigned red frame but did not feature the center port engine that the works CZ's had been using since 73. These bike were lighter and more powerful than the 73’s. Their suspensions had slightly longer travel front & rear. These CZ’s were less common on the US tracks in 74, as the Japanese moto-cross bikes were dominating the market.

1974, CZ 250cc works bike

CZ joined the long travel bandwagon in 1974. The works bikes featured forward mounted air shocks giving about 7 inches of rear wheel travel. The front forks had external preload adjusters and were extended to 8 inches of movement. These CZ’s looked cobby but were right at the FIM weight limit of 88 kg (194 lb.) These bikes were competitive with any other factory motocrosser being produced at the time.

CZ works bikes 1974

Jaroslav Falta

1974, Jaroslav Falta the true 250cc world moto-cross champion

Czech rider Jaroslav Falta, (shown in a 1973 photo) dominated the 1974 250cc world championships on his factory CZ. His crown was robbed at the final GP of the year in Switzerland by the FIM jury. Falta is the true 74 250cc world moto-cross champion!

Click here for a list of English language CZ Moto-cross tests