Motorcycle Wire Harness Layout for Flexible Device Integration

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Solution Overview

Problem

Existing straddled vehicle designs lack flexibility in accommodating additional devices due to limited connector arrangement and wiring complexity, restricting the degree of freedom in device integration.

Innovation Solution

A straddled vehicle design featuring a wire harness with a main line and branch line connected to a vehicle controller, where connectors are strategically positioned to allow for easy integration of additional devices, with protected placement in the storage box and head pipe storage portion, and a layout that facilitates electrical connections.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Volume of moving object

If connectors are densely arranged to save space, then space utilization is improved, but the degree of freedom for adding devices is reduced

Engineering Contradiction:
Improvespace utilizationVSAvoiddegree of freedom for adding devices
Core Design Contradiction:
Volume of moving objectVSAdaptability or versatility

Solution Approach 1:

The wire harness is segmented into a main line and multiple branch lines, with connectors distributed at different positions along these lines. This segmentation allows multiple connection points to be established without requiring all connectors to be densely packed in one location, thereby maintaining space efficiency while enabling flexible device addition.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

Connectors are arranged in three-dimensional space along the body frame rather than being confined to a single plane or location. The main line extends along the body frame with branch lines protruding at different positions, creating a spatial distribution that maximizes both space utilization and adaptability for additional devices.

Inventive Principle:
Principle #17Another dimension (Dimensionality change)

2Ease of manufacture

If wiring is simplified to reduce complexity, then ease of manufacture is improved, but connection flexibility for additional devices is reduced

Engineering Contradiction:
Improvewiring simplicityVSAvoidconnection flexibility
Core Design Contradiction:
Ease of manufactureVSAdaptability or versatility

Solution Approach 1:

The main line and branch line configuration serves multiple functions: it provides power and signal distribution to existing devices while simultaneously offering standardized connection points for future device additions. This universal structure eliminates the need for complex custom wiring when adding devices, maintaining both manufacturing simplicity and connection flexibility.

Inventive Principle:
Principle #6Universality (Multi-functionality)

3Ease of operation

If connectors are exposed for easy access, then ease of operation is improved, but reliability is reduced due to exposure to harmful factors

Engineering Contradiction:
Improveconnector accessibilityVSAvoidconnector protection
Core Design Contradiction:
Ease of operationVSReliability

Solution Approach 1:

The connector system is segmented into multiple connection points distributed along the wire harness, with each connector positioned at optimal locations for both accessibility and protection. This distribution allows individual connectors to be accessed when needed while the overall structure provides protection through the wire harness routing and body frame integration.

Inventive Principle:
Principle #1Segmentation

Data Source

PatentEP4493449B1Straddled vehicle
Publication Date: 2025.08.13 YAMAHA MOTOR CO LTD
  • EP4493449B1 patent drawingFigure 1
  • EP4493449B1 patent drawingFigure 2
  • EP4493449B1 patent drawingFigure 3

AI summary

A straddled vehicle (1) includes a body frame (2), a wire harness (8), and a vehicle controller (9). The body frame (2) includes a head pipe (21) that supports a steering device (3). The wire harness (8) includes a main line (MH) at least a portion of which is laid along the body frame (2) and a branch line (DH) that is branched from the main line (MH). The main line (MH) includes a first electric line (50) having one end (51) connected to a first connector (C1) and another end (52) connected to a second connector (C2) and a second electric line (60) having one end (61) connected to a third connector (C3) and another end (62) connected to a fourth connector (C4). The branch line (DH) includes a branch electric line (70) branched from an intermediate portion of the first electric line (50) and having a terminal (71) connected to the vehicle controller (9). The fourth connector (C4) is disposed at a position more rearward than the head pipe (21) and the third connector (C3) is disposed at a position more forward than the fourth connector (C4).