KTM 125, 144, 150, 200 SX, SXS, MXC, EGS, EXC, XC (1999-2010) - Comprehensive Maintenance & Repair Guide

KTM 125 / 144 / 150 / 200 — Engine & Electrical Reference Manual (SX/SXS/MXC/EGS/EXC/XC/XC-W, 1999–2010) | Art. No. 3.206.062-E

Built around KTM’s 2-stroke 125–200cc platform, this factory document covers the SX, SXS, MXC, EGS, EXC, EXC Six Days, XC, and XC-W families across model years 1999–2010. Fit is anchored by the update/edition structure and the engine-number first-digit year gates, so the correct model-year track can be matched before relying on the specification pages.

Covered platforms and capacities

• Displacement group: 125 / 144 / 150 / 200
• Model families named: SX, SXS, MXC, EGS, EXC, EXC Six Days, XC, XC-W
• Year span: 1999–2010 (loose-leaf update structure)

Year gating you can verify from the engine number

The update index maps model years by the first digit of the engine number:

• 1999 → first digit “9”
• 2000 → “0” | 2001 → “1” | 2002 → “2”
• 2003 → “3” | 2004 → “4” | 2005 → “5”
• 2006 → “6” | 2007/2008 → “7” / “8”
• 2009/2010 → “9” / “0”

What’s inside (chapter architecture)

A 12-part chapter map separates the content into discrete domains: service information, general information, engine R&I, engine teardown/assembly, component service, electrical, fuel system, technical specifications, periodic maintenance schedule, and wiring diagrams—plus a structured index layout designed for binder/loose-leaf updates.

Reference markers you’ll see repeatedly

• Document identifier on cover: Art. No. 3.206.062-E
• Update path lists multiple revision items leading up to the 2009/10 scope
• Consumables and locking compounds are specified by product name and type (e.g., Loctite 243 blue)
• Engine hardware sections include measurable boundaries for crankshaft, cylinder, piston, and clutch wear criteria

Factory identifiers and spec anchors (quick scan list)

• Edition marker shown: 07/2009
• Crankshaft journal runout limit listed as a maximum value
• Crankshaft web outer dimension is specified with a tolerance band
• Cylinder diameter classes are split by model-year break (e.g., 125cc “up to 2000” vs “from 2001” ranges)
• Piston sizing is mapped to cylinder diameter windows by piston-size index

Workshop reference highlights

The special-tools pages list KTM tool numbers and thread specs (including a Kokusan rotor extractor M27×1), while engine internals are supported by wear-limit and sizing tables (piston clearance, ring end-gap maximum, cylinder diameter windows, clutch disc thickness limits). Electrical and wiring content appears as a dedicated chapter, with wiring diagrams separated into their own section for fast navigation.

Document quick facts (for matching)

A loose-leaf/binder format is indicated, with explicit “replace/insert page” guidance and a revision chain that ties older base editions to later update packs—useful when the goal is aligning the book’s scope to a specific year band within the 1999–2010 range.

Fit-critical markers you can confirm at a glance

• Art. No. 3.206.062-E on the cover
• Model-family block: SX/SXS/MXC/EGS/EXC/XC/XC-W
• Capacity group: 125/144/150/200
• Year gates via engine-number first digit (1999–2010 mapping)

Reference details you’ll keep returning to

• Tooling list with KTM part numbers (engine stand, clutch holder, flywheel holding tools, rotor extractor)
• Numeric tolerances for crankshaft, cylinder, piston, and clutch-wear limits
• Wiring diagram section separated from general electrical pages for faster lookup

Practical scope boundary

Coverage is centered on the engine-platform and its supporting systems (electrical, fuel, cooling/lubrication references, specifications, and wiring diagrams) for the named KTM off-road model families across the 1999–2010 model-year map.