# US 8,465,039 B2 · Bike with belt transmission and its frame > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 8,465,039 B2 - Document ID: US8465039B2 - Status: Granted - Kind: B2 - Application number: 13/072,515 - Filed: 2011-03-25 - Published: 2011-10-06 - Granted: 2013-06-18 - Earliest claimed: 2010-04-01 - Assignees: Matra Manufacturing & Services - Applicants: Mickael Duvivier - Inventors: Mickael Duvivier - Web page: https://patentgrep.com/patent/US8465039B2 ## CPC - B62M 6/65: with axle and driving shaft arranged coaxially - B62K 3/02: Frames (tandem frames B62K3/14) - B62M 6/90: Batteries - B62M 9/12: the chain, belt, or the like being laterally shiftable {, e.g. using a rear derailleur} - B62M: RIDER PROPULSION OF WHEELED VEHICLES OR SLEDGES; POWERED PROPULSION OF SLEDGES OR {SINGLE-TRACK} CYCLES; TRANSMISSIONS SPECIALLY ADAPTED FOR SUCH VEHICLES (arrangements or mounting of transmissions in vehicles in general B60K; transmission elements per se F16) - B62K: CYCLES; CYCLE FRAMES; CYCLE STEERING DEVICES; RIDER-OPERATED TERMINAL CONTROLS SPECIALLY ADAPTED FOR CYCLES; CYCLE AXLE SUSPENSIONS; CYCLE SIDECARS, FORECARS, OR THE LIKE ## Abstract Bike comprising a first frame element extending from one end carrying a front wheel housing to a lower end, a second frame element extending to a lower end rigidly fixed to the first lower end, a rear fork comprising a chainstay extending from the first element to a spindle support and a seat stay extending from the spindle support to the second element, a crankset having a lateral chainring, a rear wheel driven by a sprocket inside the fork, a belt engaged with the chainring and the sprocket. The chainstay has a major portion arranged below a straight line passing through the lower ends of the chainring and of the sprocket. The belt extends through the triangle formed by the second frame element, the chainstay and the seat stay, which form an irremovable assembly. ## Claims ### Claim 1 A bike comprising: a first frame element extending from an upper end carrying a steering tube of a front wheel to a lower end; a second frame element extending from an upper end receiving a seat unit to a lower end rigidly fixed to the lower end of the first frame element; a rear wheel fork comprising at least one chainstay element extending from the lower end of the first frame element to a rear wheel spindle support and a seat stay extending from said support to the second frame element; a crankset having a crank spindle borne by the frame and a driving chainring arranged laterally outside with respect to the first and second frame elements; a rear wheel driven by a coaxial sprocket arranged inside with respect to the rear wheel fork; and a drive belt forming a continuous loop engaged with the chainring and the sprocket, wherein the chainstay element has a major portion arranged below a straight line extending from the lower end of the chainring to the lower end of the sprocket, wherein the belt has an outward strand and a return strand both extending through the triangle formed by the second frame element, the chainstay element and the seat stay, these three elements forming an irremovable stiff assembly, and wherein the axis of the crankset is situated at a vertically measured distance from the upper face of the chainstay element of the first frame element said distance being at most slightly greater than the radius of the chainring and wherein the rear wheel fork is suitable for receiving a wheel having multiple sprockets, a derailleur with an idler pulley and a chain having a return strand passing through the fork triangle and an outward strand extending below the chainstay element irrespective of the position of the derailleur. ### Claim 2 (depends on 1) Bike according to claim 1, in which the major portion of the chainstay element extends from a front end of the chainstay element which is connected to the frame, over a distance representing 60% to 80% of the total developed length of said chainstay element. ### Claim 3 (depends on 1) Bike according to claim 1, in which the major portion of the chainstay element is substantially straight from the front end of the chainstay element and is completed to the rear end of said chainstay element by a curved additional portion. ### Claim 4 (depends on 1) Bike according to claim 1, in which the major portion of the chainstay element extends in an inclined plane at an angle α comprised between 9° and 15° with respect to the horizontal. ### Claim 5 (depends on 1) Bike according to claim 1, in which the chainstay element comprises a additional portion extending from the spindle support to the major portion, which has ends aligned with a straight line forming an angle β of 30° to 45° with the horizontal. ### Claim 6 (depends on 1) Bike according to claim 1, in which the chainstay element is connected to the lower end of the first frame element, said end being situated at a distance h from the ground comprised between 12 cm and 20 cm. ### Claim 7 (depends on 1) Bike according to claim 1, in which the crankset is borne by a housing rigidly fixed to the second frame element. ### Claim 8 (depends on 1) Bike according to claim 1, in which the major portion of the chainstay element extends substantially parallel to the outward strand of the belt. ### Claim 9 Bike frame suitable for producing a bike according to any one of the previous claims, in which the first frame element, the second frame element, and the rear wheel fork comprising at least the chainstay element, the spindle support and the seat stay, form an irremovable stiff assembly, and in which a crankset housing intended for receiving a crankset has an axis situated at a vertically measured distance from the upper face of the chainstay element, said distance being at most slightly greater than the radius of the chainring of said crankset.