Briggs & Stratton 21000 Series Operating & Maintenance Instructions page 11

Specifications
CAUTION
All the components used to build this engine
assembly must remain in place for the proper
operation of this engine.
We recommend that you use an authorized Briggs &
Stratton Service Dealer for all maintenance and service
of the engine and engine parts. Use only genuine
Briggs & Stratton parts.
GENERAL INFORMATION
This is a single cylinder, air-cooled engine. It is a low
emissions engine.
In the state of California, Model Series 21000 and 21100
engines are certified by the California Air Resources
Board to meet emissions standards for 50 hours. Such
certification does not grant the purchaser, owner or
operator of this engine any additional warranties with
respect to the performance or operational life of this
engine. This engine is warranted solely according to the
product and emissions warranties stated elsewhere in
this manual.
Model Series 21000
Bore ............................ 1.575 in. (40 mm)
Stroke .......................... 1.065 in. (27 mm)
Displacement .................. 2.074 cu. in. (34 cc)
Model Series 21100
Bore ............................ 1.575 in. (40 mm)
Stroke ....................... 1.250 in. (3I .75 mm)
Displacement ................... 2.44 cu. in. (40 cc)
Note: For practicaloperation,the horsepowerloading shouldnot
exceed85%of rated
horsepower. Engine
powerwilldecrease3-1/2%
foreach1,000
feet (300 meters)
abovesea leveland 1%foreach10°
F (5.6 ° C)
above 77° F
(25 ° C).
Tune=Up Specifications
Armature air gap .. 0.010 - 0.014 in. (0.25 - 0.36 mm)
Spark plug gap ................. 0.025 in. (0.64 mm)
Valve clearance with valve springs installed and piston 1/4
in. (6 ram) past top dead center (check when engine is
cold). See Repair Manual P/N 271172.
Intake ............ 0.002 - 0.004 in. (0.05 - 0.I0 mm)
Exhaust .......... 0.002 - 0.004 in. (0.05 - 0.10 mm)
Model, Type and Code Number
To get replacement parts or technical assistance in the
future write your engine Model, Type and Code number
along with the date of purchase here. These numbers
are located on your engine. For the location, see
page 3, Engine Features.
Model Series
Type
Code
Technical Information
Power Ratings: The power ratings for an individual
engine model are initially developed by starting with
SAE (Society of Automotive Engineers) code J1940
(Small Engine Power & Torque Rating Procedure)
(Revision 2002-05). Given both the wide array of
products on which our engines are placed, and the
variety of environmental issues applicable to operating
the equipment, it may be that the engine you have
purchased will not develop the rated horsepower when
used in a piece of power equipment (actual "on-site"
power). This difference is due to a variety of factors
including, but not limited to, the following: differences in
altitude, temperature, barometric pressure, humidity,
fuel, engine lubrication, maximum governed engine
speed, individual engine to engine variability, design of
the particular piece of power equipment, the manner in
which the engine is operated, engine run-in to reduce
friction and clean out of combustion chambers,
adjustments to the valves and carburetor, and other
factors. The power ratings may also be adjusted based
on comparisons to other similar engines utilized in
similar applications, and will therefore not necessarily
match the values derived using the foregoing codes.
Emission information
Engines that are certified to meet the California Air Resources
Board (CARB) Tier 2 Emission Standards must display
information regarding the Emissions Durability Period and the
Air Index. Briggs & Stratton makes this information available to
the consumer on our emission labels. The engine emission
label wilt indicate certification information.
The Emissions Durability Period describes the number of
hours of actual running time for which the engine is certified to
be emissions compliant, assuming proper maintenance in
accordance with the Operating & Maintenance Instructions. The
following categories are used:
Moderate: Engine is certified to be emission compliant for 50
hours of actual engine running time.
Intermediate: Engine is certified to be emission compliant for
125 hours of actual engine running time.
Extended: Engine is certified to be emission compliant for 300
hours of actual engine running time. For example, a typical
walk-behind lawn mower is used 20 to 25 hours per year.
Therefore, the Emissions Durability Period of an engine with
an intermediate rating would equate to 10 to 12 years.
Certain Briggs & Stratton engines will be certified to meet the
United States Environmental Protection Agency (USEPA)
Phase 2 emission standards. For Phase 2 certified engines, the
Emissions Compliance Period referred to on the Emissions
Compliance label indicates the number of operating hours for
which the engine has been shown to meet Federal emission
requirements.
For handheld engines:
Category C = 50 hours
Category B = 125 hours
Category A = 300 hours
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