Archive for category Engines'

Yamaha engine KT-100 Tech

The crankcase Measuring each case halves is useful to determine the crankshaft end play. Add the 2 mesures together and substract the crank size. The end play should be between 0.005” and 0.010” (Photo 1-2). To change the case bearings, remove the old oil seals and place the case halves upside-down in the oven (clean […]

Yamaha KT-100 Engine

Yamaha KT-100 Engine: Junior and Senior classes Cylinder volume 97.6cc Bore/Stroke 52mm x 46mm Carburator Walbro WB-3A Compression 7.9:1 Monocylinder, 2-stroke, Pre-mix oil-gas Electronic ignition Single, forward inclined When you buy a new Yamaha KT100 it’s not quite ready for competitive racing. A minimun of preperation is required. You will find in these documents some […]

20 HP Vanguard Engine Outline Drawings

Air Cleaner Side Front View Oil Filter Side Oil Fill Side PTO Side View Footprint Crankshaft Data

Raptor III Engine Outline Drawings

Top Front Side Back Cutaway

Raptor II Engine Outline Drawings

Top Front Side Back Cutaway

WaZoom Racing Engine

What is it? The WaZoom engine is an “out-of-the-box, ready-to-race” modified engine built by West Iowa Tool. It was developed in response to the needs of tracks and associations who have expressed an interest in making the process of racing easier. All WaZoom engines come with a Total Seal crankcase to simplify and speed the […]

Identification numbers on Briggs & Stratton engines

Update your Raptor to Raptor III Specs

The new components which make Raptor II engines race friendly can be added to earlier Raptor and other Briggs & Stratton model 13 engines. Valve Guide (Oil Impregnated Bronze – large O.D. – .378) 555214 Midnight Bronze Blower Housing 555017 Cylinder head – not shot blasted 555199 Crankshaft – induction hardened crankpin and “slip fit” […]

Valve Servicing

The first step in a valve servicing procedure is to check the valve guide for wear. If the guide is worn the valve will not seat properly allowing combustion leakage. If the guide is worn remove the existing guide and replace. Once the guide is correct the seat can be cut to ensure concentricity of […]

Oil Levels and Lubrication

Lubrication Lubrication of a combustion engine is difficult due to the high temperatures and fluctuating high loads exerted. The lubricant chosen must perform several functions including the following: 1. Must have a suitable viscosity to carry heat from the engine. 2. Oiliness, to ensure adherence to the bearing for less friction and wear. 3. High […]