Other Engine Parts
About Other Engine Parts
This is the catch-all for engine parts that do not belong to the other engine groups. The products here are mainly valve shims, cylinder sleeves, bare cylinders and individual covers such as a water pump cover for a Yamaha Banshee. Owners usually come for a specific repair: restoring a worn or scored cylinder bore, or setting valve clearance after a top-end rebuild.
Valve shims are thin hardened discs sized by diameter and thickness, sold in packs. Measure the clearance on your engine with feeler gauges, compare it with the figure in your service manual, then pick the thickness that brings it back in range. The diameter must match your engine, because listings show diameters such as 8.90 mm and 9.48 mm. A cylinder sleeve is a replacement liner for the bore. When a cylinder is scored or worn past its limit, a machine shop can fit a sleeve and finish the bore to match the piston you plan to use. Sleeves are listed for specific engines, including four-stroke Yamaha Rhino 660 models.
Brands here include BOLT, Hot Rods, Vertex, Parts Unlimited and Wiseco. A rebuilt bore needs a matching piston, so look at Pistons, Rings & Piston Kits and Complete Cylinders. Reassembly takes Gaskets, Seals & Kits, and Engine Rebuild Kits & Components covers the wider rebuild. The full group is Engines & Engine Parts.
FAQs on valve shims and cylinder sleeves
How do I choose the right valve shim?
Measure the valve clearance with feeler gauges, as your manual directs, and compare it with the specified range. If the gap is outside that range, calculate the shim thickness that brings it back. Match the shim diameter to your engine first, then choose the thickness in millimeters.
What does a cylinder sleeve do?
A cylinder sleeve is a liner pressed into the cylinder to form a fresh wall for the piston and rings. It is used to repair a bore that is scored, worn or damaged. After it is fitted, the bore is machined to the size needed for the new piston.
Can I install a cylinder sleeve myself?
Most riders have a machine shop do it. The cylinder has to be bored to take the sleeve, the sleeve fitted correctly, and the bore then finished to the piston's size. Those steps need precision tools and measuring equipment.
Do I need a new piston after sleeving a cylinder?
Usually yes. The bore is finished to suit a specific piston, so the piston and rings are normally chosen with the machine shop before the work is done. Check the exact piston size they plan to use.
Why does valve clearance matter?
Valve clearance is the small gap in the valvetrain that lets each valve close fully as the parts heat and expand. If it is too tight, a valve can stay slightly open and burn. If it is too loose, the valvetrain gets noisy. Your manual gives the interval and the specification.
