The 1985-1992 Suzuki QuadRacer LT250R ATV repair manual by Clymer, covers models indicated.
Book Excerpt: 1985-1992 Suzuki QuadRacer LT250R Repair and Service Manual ENGINE (1985-1986)

This chapter contains removal, inspection, service and reassembly procedures for the 1985-1986 Suzuki LT250R engine. Although the clutch and transmission are located within the engine crankcase, they are covered in Chapter Six to simplify this material. Before beginning any engine work, re-read the service hints in Chapter One. You will do a better job with this information fresh in your mind. Refer to Table 1 for engine specifications and Table 2 for torque specifications. Table 1 and Table 2 are located at the end of this chapter.
ENGINE OPERATING PRINCIPLES Figure 1 explains how the engine works. This will be helpful when troubleshooting or repairing the engine.
ENGINE LUBRICATION Lubrication for the engine is provided by the fuel/oil mixture used to power the engine. There is no oil supply in the crankcase, as it would be drawn into the cylinder and foul the spark plug. There is sufficient oil in the mixture to lubricate the crankshaft bearings, the piston and the cylinder. The clutch and transmission have their own separate oil supply. Refer to Chapter Three for fuel/oil mixing procedure and recommended fuel-to-oil percentage.

FUEL AND EXHAUST SYSTEMS

CARBURETOR SERVICE Major carburetor service (removal and cleaning) should be performed at the intervals indicated in Table 1 in Chapter Three or when poor engine performance, hesitation and little or no response to mixture adjustment is observed. Alterations in jet size, throttle slide cutaway, and changes in jet needle position, etc., should be attempted only if you're experienced in this type of "tuning" work; a bad guess could result in costly engine damage or, at least, poor performance. If, after servicing the carburetor and making the adjustments described in this chapter, the ATV does not perform correctly (and assuming that other factors affecting performance are correct, such as ignition timing and condition, etc.) the vehicle should be checked by a dealer or a qualified performance tuning specialist. Carburetor specifications are covered in Table 1 at the end of this chapter.

Subject: 1985, 1986, 1987, 1988, 1989, 1990, 1991, 1992 Suzuki LT250R QuadRacer service, maintenance, repair. ISBN-10: 0892879084 | ISBN-13: 9780892879083 | Clymer M380-2