Tractor horsepower: choosing 50–260 HP by implement width, soil and PTO

First distinguish three powers: engine, PTO and drawbar

Horsepower on a tractor data sheet is usually engine power. On this site’s TK series, HP are calculated from engine kW—for example, the TK1204 has 88.2 kW and is listed as 120 HP. Engine power passes through the transmission and rear axle to the PTO, then through tires and soil to become drawbar power; each step involves losses. UGA materials state that a diesel tractor's rear PTO generally delivers 75–85% of rated engine power. MSU materials set, by ground condition, the share of PTO HP that can be sustained for drawbar work as 62.5% on firm ground, 55% on worked ground, and 47.5% on freshly plowed soil (after accounting for transmission, rolling resistance, slip and about a 17% overload reserve).

FAO and INTA publications point in the same direction: on a two-wheel-drive tractor, drawbar power is about 60% of PTO power; with front-wheel assist (smaller front wheels than the rear), it is about 65–68%. All 13 TK models are four-wheel drive with smaller front wheels than the rear, that is, front-wheel assist.

ImportantThe estimates in this guide narrow the selection; they are not a performance guarantee. The actual width a tractor can pull depends on soil moisture, slope, tires, ballast and the operator, and should be confirmed by a field test or local experience.

How to estimate HP by implement width

MSU bulletin E-1152 gives drawbar HP required per foot of working width. The table converts that to per meter and, following MSU examples, assigns the ground the tractor travels on: plow, chisel plow and heavy disc harrow on firm ground; the first tandem disc harrow pass on freshly plowed soil; and the field cultivator on worked ground. “Engine HP per meter” assumes the PTO delivers 80% of engine power.

MSU examples converted to metric: a 60 PTO-hp tractor working loam at 20 cm depth and 7.2 km/h can sustain about 37.5 drawbar hp, enough for a plow about 1.27 m wide, i.e. a 3-bottom 16-inch plow (1.22 m); a 4-bottom 14-inch (1.42 m) plow would overload it. Conversely, a 2.44 m (8 ft) tandem disc harrow on freshly plowed ground at 6.4 km/h requires about 29 drawbar hp, i.e. about 61 PTO-hp.

• Increasing speed by 10% raises required power by more than 10% (MSU); the table values correspond to the listed speed.
• Choose for average annual conditions, not the toughest single field; but don’t undersize on purpose—continuous overload speeds engine wear and increases slip and fuel consumption.
• The values come from extension materials for U.S. field conditions. In Latin America’s heavy clay soils, volcanic soils or high-altitude areas the differences can be large; verify with your local agricultural service or experience from similar operations.

From area and available days back to implement width

UGA recommends selecting in five steps: identify the most critical, highest-resistance task; estimate how many days are available to do it; compute the hectares per hour that must be covered; determine implement working width from that; and finally infer tractor power from the implement’s drawbar pull. Example converted to metric: 24.3 ha of sandy soil, worked twice with a tandem disc harrow and only 5 workdays of 8 h, requires 1.21 ha per hour. At 8 km/h that needs a harrow about 1.83 m wide, with a drawbar force of about 1,000 kgf and 29.4 drawbar HP; for loose or sandy soil UGA multiplies drawbar HP by 2.1, giving about 62 PTO HP. If speed is reduced to 5.6 km/h, about 43 PTO HP is sufficient, but with the same width the hectares covered per hour drop and the schedule lengthens.

For PTO-driven implements, UGA estimates PTO HP by working width or material throughput, for example:

• Disc mower: about 6.6 PTO HP per meter.
• Flail mower: about 13.5 PTO HP per meter.
• Rotary mower (blades rotate in a horizontal plane): about 34.1 PTO HP per meter.
• Small square baler: about 3.9 PTO HP per tonne per hour; large round baler: 5.6–6.7.

For rotavators, stubble mulchers and other implements common in the region, use the PTO power rating specified by the implement manufacturer as the reference.

PTO: 540 / 1000 r/min versus 720 / 760 / 850 in the TK series

ISO 500-1 (adopted in the U.S. as ANSI/ASABE AD500-1) classifies rear PTO speeds: type 1 at 540 r/min, types 2 and 3 at 1000 r/min, and type 4 at 1300 r/min. FAO and INTA publications also list common spline sizes: 35 mm with 6 splines for 540 r/min, and 35 mm with 21 splines or 45 mm with 20 splines for 1000 r/min. Implements designed to these standards will state 540 or 1000 r/min on their nameplate.

Not all PTO speeds published for the YUYAN TK series are 540 or 1000. According to this site’s product pages:

MSU notes that PTO work requires maintaining a constant PTO speed; you cannot close the throttle and shift to a higher gear as with light towing. To reduce a 760 r/min PTO to 540 r/min, the engine would operate at about 71% of its rated speed and cannot deliver its rated power; that does not replace the correct PTO specification.

ImportantIf you already have implements, send the PTO speed and spline specification from the nameplate or manual, and we will match the TK model and PTO option that we can supply directly. If you plan to buy implements as well, choose them to match the tractor’s selected PTO speed.

YUYAN TK series in three power ranges

All 13 TK tractors are four-wheel drive. The three compact models—TK504, TK504A and TK604 (50–60 HP)—use an 8+2 gearbox, have an open safety frame, and offer adjustable front and rear track width; their compact size suits small operations and narrow spaces. TK604 supports external hydraulic equipment such as a front loader or rear backhoe, and TK504A can be configured with single or dual hydraulic outlets.

The three mid-size models, TK1004, TK1204 and TK1404A (100–140 HP): the TK1004 has 12+12 shuttle-shift transmission and PTO 540/760; the TK1204 uses a dual-cylinder high-pressure lift and a larger-displacement lift pump, and its cab can be specified with fan, air conditioning, or heater; the TK1404A has a fully enclosed cab with optional air conditioning, heater and audio.

The seven high-horsepower models, TK1604, TK1604A, TK1804, TK2104, TK2104A, TK2404 and TK2604 (160–260 HP), are aimed at large-area farming; according to the product sheet, the TK2104 can work with heavy-duty implements for stubble shredding, plowing, deep tillage, subsoiling, seedbed preparation and seeding. The TK2104, TK2404 and TK2604 have 16+16 gearing and optional PTO 540/1000; the TK2404 offers draft control, position control and combined draft/position control; the TK2604 is equipped with an SDEC electronic common-rail engine, CARRARO front drive axle with hydraulic differential lock, Trelleborg radial tires and an electro-hydraulic lift control system.

PTO horsepower is estimated as 75–85% of engine power; plowing uses 62.5% of available traction on firm ground and the first harrow pass 47.5% on freshly plowed ground. Clay‑loam plowing width is about 70% of loam; sandy soil about 1.7 times.

Ballast: minimum operating mass is not working weight

K‑State notes that traction efficiency is usually best with tire slip of 8–15%, with a target near 12%: too little slip indicates excess ballast and too much wastes power and fuel. Its optimal whole‑tractor weight for front‑assist tractors (at 80% load) is about 63.5 kg per PTO horsepower at 6.4 km/h, 52.2 kg at 8 km/h and 43.1 kg at 9.7 km/h.

Estimated for heavy draft at 8 km/h: TK1204 would need about 4,630–5,240 kg and lists minimum operating mass 4,730 kg, near the lower end; TK604 about 2,320–2,630 kg versus 1,690 kg; TK2604 about 10,050–11,390 kg versus 7,735 kg. In other words, most models will need front ballast, wheel weights or tire ballast for heavy draft; lighter, faster PTO‑driven work does not require so much weight.

• Static weight distribution with front‑assist drive: about 40% front / 60% rear for towed implements and about 45% front / 55% rear for mounted implements (K‑State).
• For heavy-duty work below 6.4 km/h, K-State does not recommend relying on ballast alone.
• With added ballast, total weight must not exceed the maximum on the ROPS or cab certification plate, and must remain within the load ratings of the tires and axles.
• Radial tires typically increase productivity by 2–6% and reduce fuel consumption by 6–8% (K-State); the TK2604 uses Trelleborg radials.

Hitch, hydraulics, track width and cab

• Three-point hitch: FAO and INTA list four standardized categories; implement hitch pins must match the tractor category. Control can be draft, position, or draft/position combined. The TK2404 offers all three; the TK1604A and TK2104A have position and float control; the TK2604 has electronic lift control.
• Hydraulic outlets: first count how many circuits the implement needs (for example, a hydraulic reversible plow or hydraulic markers), then confirm the tractor’s number of outlets and flow. The TK504A accepts single or dual outlets; the TK1604A and TK2104A have hydraulics with independent supply.
• Track width: the TK504 front track is adjustable in steps at 950 / 1150 / 1250 mm and the rear is stepless 960–1300 mm; the TK2104, TK2404 and TK2604 have a rear track of 1,700–2,300 mm. For row crops, set the track to match row spacing to avoid crop damage.
• Cab: the three compact models have open rollover protection; the TK1204 cab can be fitted with a fan, air conditioning, or heater; the TK1804, TK2104 and TK2604 have enclosed cabs with air conditioning, and the TK2404 includes air conditioning as standard. In hot or dusty areas, consider an enclosed cab, which the spec sheet notes reduces dust and noise.

FAO and INTA also note that, among similar models, dealer and service proximity, parts availability, and maintenance support often matter more than a few HP. When requesting a quote, include a list of common wear parts and your preferred supply method.

Before import: emissions and local requirements

The TK series engine is marked China III emissions, which refers to China’s Stage III standard for non-road mobile machinery; it is not equivalent to an EU Stage IV / V certificate. These are the non-road emission provisions related to farm tractors in three countries, as checked by this site in November 2026:

The table covers emissions only. Taxes, registration, safety requirements, machine cleaning and other import requirements must be confirmed item by item with your local customs broker before placing an order.

ImportantYUYAN can assist in providing engine and machine documentation, preparing export paperwork, and coordinating information needed for customs clearance and local import admission; approval, clearance timing and local registration are determined by the destination country authorities, and YUYAN does not guarantee them.

What to specify when requesting a quotation

This site does not publish tractor prices. Send the type of work, soil, the implements you use most and their widths, PTO speed, destination port and quantity, and YUYAN will provide a written quotation based on the actual configuration.