FAQ Gearbox - different top speeds Zetor UR1

[Joachim]

Gearbox - different top speeds Zetor UR1

Introduction
Important! This summary is not intended to be a tuning guide, but merely to document the differences. Anyone who makes the changes listed below to a Zetor tractor used in road traffic is acting with gross negligence and expressly at their own risk and responsibility!

Changes to the gearbox

Known only from Zetor 5211, 6211 and 7211 as well as 7711 - here, different gear pairings were used than in 6011, 7011 gearboxes and their predecessors in order to make the higher engine power bearable for the gearboxes.​

The Zetor 5011 transmission and its direct ancestors 4911, 4712, up to the 3011 had mWn. largely identical gear pairings, the differences in the final speeds result from the following points.​

Changes to the portals

Zetor saw pretty much the simplest but not entirely cheap way to increase the final speed in the portals. Officially there were 3 gear pairings:​

• 62/11 for 25 km/h
• 61/12 for 30 km/h
• 59/14 for 40 km/h

The first number indicates the number of teeth on the large gear and the second number indicates the number of teeth on the small, upper gear. The housings have remained identical, so theoretically this could be converted.​

Changes to tires

Of course, a higher top speed can also be achieved even more easily than with the modified portals with larger tires, although not in such large steps as with the modified portals.​

3-5 km/h more can be achieved with the next larger wheels, depending on the existing wheels/tires and the new wheels.​

This is also a measure that in Germany should at least be presented and approved by TÜV/Dekra!​

Changes to the engine (ESP)

We have to warn you in advance - stay away!! The engines of the Zetor UR1 are all equipped with bearing shells and turning the ESP "high" brings more speed to the gearbox and therefore certainly a little more top speed. But this shortens the life of the engine enormously and increases diesel consumption. Therefore, technically possible but not sensible and certainly not allowed!​

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So what remains to be said in conclusion - Zetor had used quite simple ways to increase the top speeds, most of which can still be carried out later today, but they are usually not immediately legal and it is therefore not advisable to do this.