1987 Honda Fourtrax TRX 250X Repair and Service Manual (P/N 61KB500)

• Official 458-page Honda factory publication (P/N: 61KB500), originally released in November 1986.
• Covers the 1987 Honda Fourtrax TRX 250X, documenting exact factory specifications, maintenance intervals, and engine service parameters for the 246cc air-cooled 4-stroke powertrain.
• Contains 18 distinct chapters detailing internal systems including the cylinder head, piston assembly, clutch, oil pump, and kick starter mechanisms.
• Delivers complete repair documentation, essential wiring diagrams, and comprehensive workshop procedures for professional mechanics.
• Explains the dual valve carburetor, 5-speed transmission, hydraulic brakes, double wish-bone front suspension, and alternator subassemblies.

Service and Technical Overview

This official OEM manual delivers the raw, unedited engineering data required to properly maintain or overhaul the TRX 250X. Whether you are splitting the cases on the bench or troubleshooting the electrical system, this reference gives you direct access to the specific numbers Honda engineers established. The content targets professional rebuilds and serious garage projects. The distinct advantage of utilizing this specific PDF publication at your workbench is the significant reduction in diagnostic time; having precise wear limits, cable routing drawings, lubrication system flow views, exploded parts views, troubleshooting charts, and torque tables directly in front of you prevents costly reassembly errors. It provides the step-by-step repair instructions necessary to successfully tackle high-labor-cost jobs yourself, such as refacing valve seats, pressing new valve guides, and completely rebuilding the 5-speed constant mesh transmission. It breaks down the 246cc engine and chassis into dedicated chapters, covering essential fuel, electrical, and suspension tuning parameters. Always adhere to standard shop safety practices and double-check your lifting points before beginning heavy tear-downs, as improper chassis support during component removal can lead to severe injury or equipment damage.

Engine and Chassis Specifications

Precision is critical when rebuilding a top end or assembling internal components. The technical data provided includes comprehensive torque tables, wear limits, and tolerance charts for valve springs, rocker arms, and piston clearances. Engine oil capacity is strictly documented at 2.0 liters for a dry fill following complete disassembly. To prevent mechanical failure and ensure optimal compression, intake and exhaust valve clearances must be set to precisely 0.10 mm. Furthermore, the cylinder head bolt torque demands a strict 35–45 Nm rating to prevent cylinder warpage.

Experienced engine builders know that this specific 246cc powertrain has unique pitfalls. For instance, attempting to force the primary drive gear lock nut in the standard removal direction will instantly strip the crankshaft, as it utilizes a reverse left-hand thread. Additionally, inexperienced mechanics often ruin the carburetor body by over-tightening the pilot screw against its delicate seat, or they warp the aluminum cylinder head by using an open torch instead of controlled heat (212–300°F) to extract valve guides. Having these exact factory specifications on hand ensures the ATV leaves your shop performing exactly as it did rolling off the assembly line.