with reference now to the drawings , and in particular to fig1 through 5 thereof , a new rotary motor using pistons embodying the principles and concepts of the present invention and generally designated by the reference numeral 10 will be described . as best illustrated in fig1 through 5 , the rotary motor using pistons 10 generally comprises a main housing 20 , a plurality of pistons 30 , an inlet port 40 , and outlet port , 41 , a spark plug 43 , a plurality of plate members 50 - 51 , a drive shaft 56 , and a fly heel assembly 60 . the inlet port 40 in environmental communication with the interior of the main housing 20 . the interior includes an annular outer portion . the outlet port 41 in environmental communication with the interior of the main housing 20 . a spark plug port 42 is used for receiving the spark plug 43 such that a firing end of the spark plug 43 is environmental communication with the interior of the main housing 20 . the first plate member 50 is coupled within the main housing 20 such that the first plate 50 is rotatable within the interior of the main housing 20 . the second plate member 51 is coupled within the main housing 20 such that the second plate 51 is rotatable within the interior of the main housing 20 . each of the pistons 30 is coupled to an associated one of the first 50 and second plates 51 such that the pistons 30 divide the annular outer portion of the interior into a plurality of chambers between adjacently positioned pistons 30 . the inlet port 40 is designed for coupling to a combustible substance source for injecting a combustible substance into each of the chambers when each chamber is positioned adjacent to the inlet port 40 . the spark plug 43 is for igniting the combustible substance in each of the chambers when each of the chambers is positioned adjacent to the spark plug port 42 . thus each adjacently positioned chamber is compressed when the spark plug 43 ignites and an oppositely positioned chamber is expanded when the spark plug 43 ignites . a first one of the adjacently positioned chambers is adjacent to the outlet port 41 when the spark plug 43 fires . thus combustion residue is expelled from the first one of the adjacently positioned chambers when the first one of the adjacently positioned chambers is compressed . the opposite chamber is positioned adjacent to the inlet port 40 . thus the combustible substance is injected into the opposite chamber when the spark plug 43 ignites . a second one of the adjacent chambers is compressing the combustible substance when the spark plug 43 ignites . the drive shaft 56 is coupled to one of the first 50 and second plates 51 . thus the drive shaft 56 is turned by rotation of the one of the first 50 and second plates 51 . the drive shaft 56 extends out of the main housing 20 . an anti - reverse clutch 58 is operationally coupled to the drive shaft 56 for preventing the drive shaft 56 from rotating in a reverse direction . a first one of the pistons 30 is coupled to an outer edge of the first plate 50 such that the first piston is positioned in the outer portion of the interior of the main housing 20 . a second one of the pistons 30 is coupled to the outer edge of the first plate 50 opposite the first piston . the second piston is positioned in the outer portion of the interior of the main housing 20 . a third one of the pistons 30 coupled to an outer edge of the second plate 51 . the third piston is positioned in the outer portion of the interior of the main housing 20 between the first piston and the second piston thus a first chamber is formed between the first and third pistons and a second chamber is formed between the third and second pistons . a fourth one of the pistons is coupled to the outer edge of the second plate 51 . the fourth piston is positioned in the outer portion of the interior of the main housing 51 between the first and second pistons and opposite the third piston . thus a third chamber is formed between the first and fourth pistons and a fourth chamber is formed between the fourth and second pistons . the drive shaft 56 extends from a center of a first face of the first plate 50 and through a center of the second plate 51 . the second plate 51 includes an annular wall extending from the second plate 51 around the drive shaft 56 and out of the main housing 20 . the flywheel assembly 60 comprises a flywheel axle 61 which is integrally coupled to the drive shaft 56 , a first plate flywheel 62 , a plurality of first plate magnets 63 , a first plate coil 64 , a first plate flywheel cover 65 , a second plate flywheel 66 , a plurality of second plate magnets 67 , a second plate coil 68 , and a second plate flywheel cover 69 . the flywheel axle 61 extends from a center of a second face of the first plate 50 and out of the main housing 20 . the first plate flywheel 62 coupled to the flywheel axle 61 . thus the first plate flywheel 62 is rotated by the flywheel axle 61 when the first plate 50 rotates . the plurality of first plate magnets 63 is coupled to the first plate flywheel 63 . the first plate flywheel coil 64 is coupled to the main housing 20 such that the plurality of first plate magnets 63 pass over the first plate flywheel coil 64 when the first plate flywheel 62 is rotated . the first flywheel cover member 65 is coupled to the main housing 20 for covering the first plate flywheel 62 . the second plate flywheel 66 is coupled to the annular wall of the second plate 51 . thus the second plate flywheel 66 is rotated by the annular wall of the second plate 51 when the second plate 51 rotates . the plurality of second plate magnets 67 is coupled to the second plate flywheel 66 . the second plate flywheel coil 68 is coupled to the main housing 20 such that the plurality of second plate magnets 67 pass over the second plate flywheel coil 68 when the second plate flywheel 66 is rotated . the second flywheel cover member 69 is coupled to the main housing 20 for covering the second plate flywheel 66 . the first plate flywheel 62 includes an annular first plate recessed track facing the main housing 20 . the plurality of first plate magnets 63 is positioned in spaced relationship to each other in the first plate recessed track . the second plate flywheel 66 includes an annular second plate recessed track facing the main housing . the plurality of second plate magnets 67 is positioned in spaced relationship to each other in the second plate recessed track . the main housing 20 includes a plurality of cooling holes 28 for facilitating cooling of the main housing 20 during use . the main housing includes a pair of annular cylinder wall members 23 . the annular cylinder wall members 23 are positioned in the interior of the main housing 20 . each of the annular cylinder wall members 23 includes a first planar portion 24 for clamping between a first main housing member 21 and a second main housing member 22 . a second planar portion 25 is positioned in a central portion of the interior of the main housing 20 . a medial portion 26 extends between the first 24 and second planar portions 25 . the medial portion 26 includes an arcuate cross - section along a radial axis of the annular cylinder wall member 23 . the medial portion 26 is for positioning in the annular outer portion of the interior of the main housing 20 such that the pistons 30 are positioned between the medial portions 26 of the annular cylinder wall members 23 . one of the annular cylinder wall members 23 includes an aperture 27 which is alignable with the spark plug port 42 for facilitating environmental communication between the spark plug port 42 and the outer annular portion of the interior of the main housing 20 . each of the pistons 30 includes a first compression ring 33 which is located proximate a leading edge 31 of the piston 30 and a second compression ring 34 which is located proximate a tailing edge 32 of the piston 30 . each of the pistons 30 is coupled to the associated one of the first 50 and second plates 51 by an associated wrist pin 37 for permitting pivoting of the piston 30 relative to the associated one of the first 50 and second plates 51 for preventing binding at high speeds . each of the pistons 30 includes a first oil ring 35 which is located proximate the first compression ring 33 and a second oil ring 36 which is located proximate the second compression ring 34 . a first bearing 54 is positioned between the flywheel axle 61 and an interior end of a first one of the annular cylinder wall members 23 . a second bearing 55 is positioned between the annular wall member of the second plate 51 and an interior end of a second one of the annular cylinder wall members 23 . as to a further discussion of the manner of usage and operation of the present invention , the same should be apparent from the above description . accordingly , no further discussion relating to the manner of usage and operation will be provided . with respect to the above description then , it is to be realized that the optimum dimensional relationships for the parts of the invention , to include variations in size , materials , shape , form , function and manner of operation , assembly and use , are deemed readily apparent and obvious to one skilled in the art , and all equivalent relationships to those illustrated in the drawings and described in the specification are intended to be encompassed by the present invention . therefore , the foregoing is considered as illustrative only of the principles of the invention . further , since numerous modifications and changes will readily occur to those skilled in the art , it is not desired to limit the invention to the exact construction and operation shown and described , and accordingly , all suitable modifications and equivalents may be resorted to , falling within the scope of the invention .