2000–2007 KTM 250 EXC, 400/450/520/525 Racing, 540 SXS, 560 SMR & 610 CRATE Repair Manual (P/N 3.206.043-E)

KTM repair manual P/N 3.206.043-E, edition 01/2007, covers the 2000–2007 Racing engine family: 250 EXC, 400/450 and 520/525 variants, 540 SXS, 560 SMR, and 610 CRATE. Model-specific specifications and regional wiring diagrams distinguish the configurations within this range.

• Engine repair: Engine removal and reinstallation, crankcase separation, crankshaft and balancer-shaft service, cylinder-head work, valve-guide replacement, and timing-chain installation.

• Clutch and transmission: Hydraulic-clutch bleeding, clutch wear checks, main-shaft and countershaft assembly, shift-mechanism inspection, and starter freewheel-hub replacement.

• Lubrication and cooling: Oil-circuit diagrams, oil-pump inspection, long and short filter servicing, water-pump seal work, and cooling-system bleeding.

• Keihin fuel systems: FCR and FCR-MX carburetor disassembly, component inspection, accelerator-pump adjustment, float-height checks, and throttle position sensor testing and adjustment.

• Electrical diagnosis: KOKUSAN ignition tests, stator and pulse-generator checks, starter-circuit diagnosis, charging-system measurements, and regional wiring diagrams.

• Workshop reference: Exploded component views, illustrated special-tool listings, wear-limit charts, transmission ratios, torque tables, suspension settings, fluid capacities, and periodic maintenance schedules.

KTM wrote this manual for qualified, professionally trained mechanics and assumes familiarity with general workshop procedures.

Engine, Clutch, and Lubrication Service

The engine chapters cover piston fitting clearances, crankshaft-journal runout, connecting-rod bearing play, and valve-train wear. Cylinder-head work includes valve-guide replacement and camshaft service, with separate instructions for the water-pump seal carrier and timing-chain tensioner.

Clutch revisions: The drawings distinguish early clutch assemblies from later designs, including changes to bearings, supporting washers, and clutch-disc arrangements. These distinctions help match the inspection and assembly information to the components on the bench.

Starter drive: Inspection covers the kickstarter, electric-starter reduction gear, later torque limiter, and freewheel hub. The manual identifies starter-drive components that must be replaced together when damaged.

The oil-circuit drawing traces flow through the long and short filters, bypass valve, connecting-rod bearing, and piston-cooling jet. A specific warning explains how incorrect crankpin alignment can interrupt bearing lubrication and damage the connecting-rod bearing.

Hot engine oil and coolant present burn hazards; follow the manual's precautions during draining and cooling-system work.

Keihin Carburetors and Throttle Sensors

Separate procedures cover FCR 35/39 and FCR-MX 37/39/41, with different FCR-MX disassembly instructions for earlier and later designs. Component checks address the choke slide, hot-start mechanism, jet needle, needle jet, float valve, and throttle-slide coating.

The accelerator-pump section explains the difference between changing injection timing and changing delivery quantity. Throttle position sensor procedures use resistance measurements, while the carburetor-setting tables distinguish regional and restricted configurations.

KOKUSAN Tests and Circuit Diagrams

The electrical chapter separates 4K-3A and 4K-3B tests and provides static ignition and static/dynamic generator measurements. It specifies peak-voltage adapter 584.29.042.000, along with ignition-coil resistance checks and charging-voltage test conditions.

CDI-unit testing requires an ignition test bench; the manual warns that ordinary measuring equipment can damage its electronics. Troubleshooting charts address no-crank, no-start, poor running, overheating, and battery-discharge symptoms.

Diagram coverage includes the lubrication-system exploded view, Keihin carburetor exploded views, main-harness schematics, CDI/starter circuits, lighting/instrument circuits, and turn-signal circuits. Later diagrams add connector identifiers, pin numbers, and separate positive- and ground-connection sheets.

Chassis Reference and Maintenance Scope

Front and rear brake-fluid replacement procedures are included. Brake-pad and disc inspection refers to the owner's manual. Fork and shock coverage consists of specification and adjustment tables plus maintenance schedules; this publication does not provide internal suspension-overhaul procedures.

The original loose-leaf updating instructions and revision history remain included. Maintenance charts distinguish routine checks from additional engine inspections for competition and private use.

A Preview of Crankshaft Clearances and Float Settings

These examples are a small selection of the manual's assembly and carburetor specifications.

Crankshaft axial clearance is 0.25–0.35 mm; a new or overhauled 560 SMR crankshaft has a separate 0.35–0.45 mm specification.

For the Keihin FCR 35/39, float height is 9 mm, measured with the float resting against the needle valve without compressing it. The FCR-MX check uses float alignment instead of this dimension.

PDF Search, Bookmarks, and Diagram Detail

Search and diagram navigation: Service text and specification tables are searchable, but some wiring-diagram labels are outside the searchable text layer. Embedded bookmarks link to chapters and subsections. Small wire-color codes and connector numbers in dense schematics require zooming.

One printable English 245-page PDF contains 217 technical and reference pages, seven cover and preliminary pages, and 21 blank pages. Covers, updating instructions, the introduction, and the reply form are already included in that total.