honda crf 250

Bolt
On
suitable for:
HONDA CRF 250
2010-2011
CYLINDER, PISTON, GASKET KIT
BIG BORE Ø 82 mm / 284.1 cc
TECHNICAL
CHARACTERISTICS
P400210100033
ATHENA launches its new BIG BORE kit for HONDA CRF 250, developed in cooperation with the most important Motocross World Teams and tested simulating the worst possible conditions to reach the best performances. The aluminum cylinders come with a coated
steel liner, which results in a larger bore but maintaining the stock external diameter of the hub. No case modification required, just bolt
it on and go! ATHENA have matched the cylinder with a forged piston which has a higher compression ratio than that of the OE, we
intended to reach the best performances ever. The gaskets have been developed using last generation technologies; in particular the
multilayers head gasket has been redesigned to be suitable to the new dimensions and performance of the BIG BORE cylinder kit.
SPARE
PARTS
P/N:
- S4F08200004A
- S4F08200004B
- P400210160024
Forged piston Ø 81.95;
Forged piston Ø 81.96;
Gasket kit;
TECHNICA LDATA
OEM
CYLINDER BORE
82 mm
76.8 mm
STROKE
53.8 mm
53.8 mm
DISPLACEMENT
284.1 cc
249 cc
13.5:1
13.21:1
29.3 kW / 39.3 HP / 11600 rpm
25.65 kW / 34.4 HP / 10990 rpm
COMPRESSION RATIO
WHEEL POWER
ATHENA Ø 82
OEM
PowerA [Max = 39.3]
35
25
PowerA
POWER CURVES
30
20
15
10
4000
5000
6000
ATHENA [29.3 kW / 39.3 HP]
Test made with:
- ATHENA Cylinder kit Ø 82 mm.
7000
8000
9000
EngSpd RPM
10000
11000
OEM [25.65 kW / 34.4 HP]
Test made with stock engine.
ATHENA SUGGESTS TO USE ALSO:
OPTIONAL
12000
- FFC007 Oil filter (not included);
- S410210200069
Air filter (not included);
- P400210400095
Engine oil seal kit(not included).
13000
STRENGHT POINTS
1. Projects use 3D Solid Modelling software creating
virtual simulation and verification of mechanical
stresses.
2.Aluminium cylinder cast in steel moulds and manufactured by CNC machines to assure millesimal
tolerances during all manufacturing phases.
3.Redesigned water jackets to increase capacity
4. Cylinder liner with a special silicon carbide and nickel coating mixture to grant the best fluidity of the
piston and durability of the cylinder.
5.Lapping performed in rooms with indoor temperatures of around 20 degrees, in order to have an
excellent control of the boring and of each cylinder
quality.
6. Cylinder support surfaces are perfectly parallels in
order to eliminate any matching inaccuracy.