Frame for cycles, in particular for mountain bikes

1. A frame ( 10 ) for cycles ( 1 ), comprising:

a seat tube ( 11 ) to the top end ( 11 a ) of which a saddle ( 12 ) is to be connected, and

a front structure ( 14 ) and a rear structure ( 15 ) which have, in side view, a generally V-shaped configuration with the ends ( 14 a , 14 b ; 15 a , 15 b ) connected to the seat tube ( 11 ) and the respective vertices ( 14 c , 5 c ) facing in opposite directions relative to the seat tube ( 11 ),

wherein the front structure ( 14 ) and the rear structure ( 15 ) are substantially identical to one another and interchangeable and have respective first ends ( 14 a , 15 a ) connected to an end portion ( 11 a or 11 b ) of the seat tube ( 11 ) and respective second ends ( 14 b , 15 b ) connected to a central or intermediate portion ( 11 c ) of the seat tube ( 11 ), whereby the frame ( 10 ) is adapted to assume selectively one of a plurality of different configurations by rotating one or both of said structures ( 14 , 15 ) and connecting the first end ( 14 a , 15 a ) of the or each rotated structure ( 14 , 15 ) to the other end portion ( 11 b or 11 a ) of the seat tube.

2. A frame for cycles according to claim 1 in which, in side view, the vertices ( 14 c , 15 c ) and the ends ( 14 a , 14 b ; 15 a , 15 b ) of the front structure ( 14 ) and of the rear structure ( 15 ) define respective isosceles triangles.

3. A frame for cycles according to claim 1 in which, in side view, the vertices ( 14 c , 15 c ) and the ends ( 14 a , 14 b ; 15 a , 15 b ) of the front structure ( 14 ) and of the rear structure ( 15 ) define respective scalene triangles, right-angled triangles.

4. A frame for cycles according to claim 1 in which each of the front structure ( 14 ) and the rear structure ( 15 ) comprises two identical V-shaped elements ( 16 , 18 ; 17 , 19 ) having their ends connected to the seat tube ( 11 ) and their respective vertices spaced apart transversely.

5. A frame for cycles according to claim 4 in which the V-shaped elements ( 16 , 18 ; 17 , 19 ) of the same structure ( 14 , 15 ) have their homologous ends interconnected, by welding.

6. A frame for cycles according to claim 1 in which the front structure ( 14 ) has an end ( 14 a ) connected to the upper end portion ( 11 a ) of the seat tube ( 11 ).

7. A frame for cycles according to claim 1 in which the front structure ( 14 ) has an end ( 14 a ) connected to the lower end portion of the seat tube ( 11 ).

8. A frame for cycles according to claim 1 in which the rear structure ( 15 ) has an end ( 15 a ) connected to the upper end portion ( 11 a ) of the seat tube ( 11 ).

9. A frame for cycles according to claim 1 in which the rear structure ( 15 ) has an end ( 15 a ) connected to the lower end portion ( 11 b ) of the seat tube ( 11 ).