Speed Reducers Overview

Speed Reducers.

Cotta speed reducers match engine speed to driven equipment speed allowing both the engine and load to operate at peak efficiency. These compact and heavy duty gearboxes are designed for use with the commercial offerings of major engine manufacturers.

Cotta engine mounted speed reducers are available with SAE flyweeel housings from #5 to #00, ratios to 8, and horsepower capacity to 2200. Above 2200 HP, remote mount models are generally used.

Flywheel connection options include over center clutches, air clutches, drive plates and torsional couplings. Independent mount units are also available. Cotta speed decreasers are easily modified to meet special application needs.

Typical applications are, pumps, generators, rock crushers, compressors, mud pumps, blenders, and wood chippers. Some speed reducers have side load capability for belt driven applications.

Many pre-designed special purpose speed decreasers are available. If our catalog offerings do not meet your needs, please ask a Cotta Sales Engineer about a modified standard or custom speed reducer.

See the tabulation of standard units below or click here to open a complete speed reducer catalog in PDF format.  Request a quote

Note: the following table contains generalized information. many features such as clutch size and bell housing selection affect weight and installation dimensions. Ratios differ from engine to anti engine rotation. Click on an individual model to get exact dimensions, ratios, and available options.

Speed Reducer Tabulation

MODEL TORQUE CAPACITY (LB-FT) MAX RATIO STD SAE HSG SIZE WT. (lbs) a b c d e f OUTPUT SHAFT DIA.
AR2053A
AR2053E
350
325
4 2 400 14.62 5.65 16.12 21.75 5.5 9.13 2.25
SR2A
SR2E
800
600
4 1 800 18.5 6.2 22.0 29.0 7.0 11.0 3.0
SR700A
SR700E
650 1.95 1 560 21.18 5.5 14.0 18.0 6.25 6.5 3.0
SR3A
SR3E
1400
950
3.89 0 975 24.0 6.4 25.0 33.0 8.00 12.5 3.0
GR15A
GR15E
1450 2.46 1 1230 25.38 5.5 21.0 23.5 9 8.75 4.0
GR16A
GR16E
1650 3 0 1530 28.25 9.0 25.0 25.75 10.25 9.75 4.0
GR1600A
GR1600E
3000
2600
3 00 1530 28.25 9.0 25.0 25.75 10.25 9.75 4.0
GR3200A
GR3200E
5500
4500
3.1 00 2000 28.15 7.0 41.0 37.3 11.75 15.75 4.75
Model AR2053A
AR2053E
TORQUE CAPACITY(LB-FT) 350325
MAX RATIO 4
STD SAE HSG SIZE 2
WT. (lbs) 400
a 14.62
b 5.65
c 16.12
d 21.75
e 5.5
f 9.13
OUTPUT SHAFT DIA. 2.25
Model SR2ASR2E
TORQUE CAPACITY(LB-FT) 800600
MAX RATIO 4
STD SAE HSG SIZE 1
WT. (lbs) 800
a 18.5
b 6.2
c 22.0
d 29.0
e 7.0
f 11.0
OUTPUT SHAFT DIA. 3.0
Model SR700ASR700E
TORQUE CAPACITY(LB-FT) 650
MAX RATIO 1.95
STD SAE HSG SIZE 1
WT. (lbs) 560
a 21.18
b 5.5
c 14.0
d 18.0
e 6.25
f 6.5
OUTPUT SHAFT DIA. 3.0
Model SR3ASR3E
TORQUE CAPACITY(LB-FT) 1400950
MAX RATIO 3.89
STD SAE HSG SIZE 0
WT. (lbs) 975
a 24.0
b 6.4
c 25.0
d 33.0
e 8.00
f 12.5
OUTPUT SHAFT DIA. 3.0
Model GR15AGR15E
TORQUE CAPACITY(LB-FT) 1450
MAX RATIO 2.46
STD SAE HSG SIZE 1
WT. (lbs) 1230
a 25.38
b 5.5
c 21.0
d 23.5
e 9
f 8.75
OUTPUT SHAFT DIA. 4.0
Model GR16AGR16E
TORQUE CAPACITY(LB-FT) 1650
MAX RATIO 3
STD SAE HSG SIZE 0
WT. (lbs) 1530
a 28.25
b 9.0
c 25.0
d 25.75
e 10.25
f 9.75
OUTPUT SHAFT DIA. 4.0
Model GR1600AGR1600E
TORQUE CAPACITY(LB-FT) 30002600
MAX RATIO 3
STD SAE HSG SIZE 00
WT. (lbs) 1530
a 28.25
b 9.0
c 25.0
d 25.75
e 10.25
f 9.75
OUTPUT SHAFT DIA. 4.0
Model GR3200AGR3200E
TORQUE CAPACITY(LB-FT) 55004500
MAX RATIO 3.1
STD SAE HSG SIZE 00
WT. (lbs) 2000
a 28.15
b 7.0
c 41.0
d 37.3
e 11.75
f 15.75
OUTPUT SHAFT DIA. 4.75
  • All dimensions are in inches.
  • Bell housing are standard for the model shown. Chart dimension “A” is base upon that standard. Consult individual spec sheets for optional bell housing dimensions.
  • Standard output shaft location for speed reducers is 6 o’clock to the input (as shown).
  • Cotta speed reducers are designed to be driven clockwise facing the input shaft.
  • Refer to individual spec sheets for speed limitations.
  • Speed reducers require rear supports.

Note: in order to specify a speed reducer we will need the following information:

  • Input speed
  • ideal output speed
  • flywheel housing size
  • flywheel connection requirement (clutch, drive plate, torsional coupling, etc.)
  • direction of rotation (engine or anti engine)
  • type of driven equipment