ConCar Variable Speed Belts 52x16 – 1,400 mm inner length – DIN 7719 / ISO 1604
This ConCar Variable Speed Belts with a 52x16 profile and a 1400 mm inner length, is a toothed variator belt conforming to DIN 7719 and ISO 1604. Variable Speed Belts are the mechanical alternative to frequency converters: they regulate the output speed purely through geometry, without electronics, harmonics, or an additional heat source in the control cabinet. In many woodworking, textile, and agricultural machines, this remains the more robust solution because it operates reliably even in dusty, humid, and vibration-prone environments.
The inner length of 1,400 mm is a standard length in the mid-range for the 52x16 profile. For reference: With two pulleys of the same size, each with an effective diameter of 355 mm, the corresponding center distance is approximately 180 mm. At a belt speed of 20 m/s, the belt rotates around 13.6 times per second. This combination of moderate bending frequency and sufficient wrap is the reason why most series production drives operate within this length range.
For design and comparison with an existing belt, the three length specifications are important because manufacturers use different reference dimensions. The inner length (Li) is 1,400 mm; it is measured at the inner circumference of the belt and is the standard ordering dimension in Germany. The effective length (Ld) of 1,475 mm refers to the neutral axis and is the dimension used in many catalogs and drive calculations. The outer length (La) of 1,501 mm is measured at the back of the belt. With a profile height of 16 mm, the difference between the inner and outer lengths is 101 mm, which corresponds to twice the difference in circumference across the belt height. When replacing an old belt, always compare using the same reference dimension; otherwise, you can easily be off by several centimeters.
Internal length (Li): 1,400 mm
Effective length (Ld): 1,475 mm
External length (La): 1,501 mm
Profile: 52x16 according to DIN 7719 / ISO 1604
Top width: 52 mm
Height: 16 mm
Flank angle: 27°
Construction: open-sided, toothed
Mixture: Chloroprene (CR)
Tensioning material: Polyester cord
Antistatic: yes, according to ISO 9563
Temperature range: -30 °C to +80 °C
Belt speed: up to 30 m/s
Weight: 1.338 kg
Article number: G452161400
EAN: 4059213024194
Manufacturer: ConCar
The belt consists of a chloroprene blend (CR) with an embedded polyester tensile cord. Chloroprene was deliberately chosen here: it is resistant to oil mist, ozone, UV radiation, and weathering, and retains its elasticity in a temperature range of approximately -30 to +80 degrees Celsius. The polyester cord absorbs the tensile forces and keeps elongation low over the belt's lifespan, which is particularly important in a variator because an elongated belt length directly translates into a shift in the control range.
The 27° flank angle is the crucial difference compared to a conventional V-belt, which operates at 34 to 40 degrees. The shallower angle generates less wedging effect per millimeter of radial travel, ensuring smooth belt operation across the entire pulley adjustment range and preventing binding at the end positions. Simultaneously, the large 52 mm upper width provides the necessary contact area to transmit torque solely through friction. The toothed underside reduces bending stiffness to such an extent that the belt can operate even on small effective diameters without the flanks overheating due to internal flexing.
Belts of this size are used in heavy-duty drives: threshing and drum drives on combine harvesters, intake and chopping units on forage harvesters, sawing and chipboard plants, large conveying and crushing plants, as well as compressor and blower drives where the speed must follow the demand without shifting a gearbox.
What these applications have in common is that the rotational speed must be adjusted during operation to suit the material, batch, or demand. A Variable Speed Belts solves this problem purely mechanically, without any electronics in the drive train. This is advantageous wherever dust, moisture, vibration, or temperature would damage a frequency converter, and it remains the only economical solution for existing machines because the variator is an integral part of the machine's design.
Before ordering, check the adjustment range of your drive. The belt must be able to be fitted without force, whether the pulleys are fully closed or open. After fitting, tension the belt to the tension specified by the machine manufacturer and check again after the break-in period. If several belts run in parallel in one drive, they must always be replaced as a complete set, as a new belt, in addition to worn ones, bears the entire load.
Before you classify a belt as worn, it's worth taking a look at the pulley. A worn groove allows the belt to sink deeper, causing it to sit on the bottom of the groove and lose contact with the belt flanks. This manifests as a sudden loss of power, even with a seemingly new belt. This can be checked in a minute using a groove feeler gauge.
Variable Speed Belts are standardized according to DIN 7719 and ISO 1604. A belt with a 52x16 profile and a 1400 mm inner length is therefore dimensionally identical regardless of the manufacturer; no modification of the pulleys is required for replacement. This ConCar belt replaces, among others:
OPTIBELT: VB 52x16 / VARIO POWER 52x16
GATES: Multi-Speed 52x16 / Predator V Variable Speed
CONTITECH: VARIO Speed 52x16 / CONTI-V VARISPEED
MEGADYNE: VARISECT 52x16
MITSUBOSHI: VARI-SPEED 52x16
BANDO: Variable Speed 52x16
PIX: Variable Speed 52x16
The belt is supplied as a single, endless belt. Standard lengths and common profiles are available from stock; custom lengths and widths are available upon request. If you are unsure which length your drive requires, please send us the part number of your old belt or the dimensions of your pulleys, and we will check the compatibility.