{"product_id":"castair-replacement-motor-pulley-1-3-8-fixed-bore-shaft-8-0-od-2b-grooves","title":"Castair Replacement Motor Pulley 1 3\/8\" Fixed Bore Shaft 8.0\" OD. 2B Grooves","description":"\u003cp\u003eThe Castair P2B80-13\/8 is a 2-groove (2B) replacement motor pulley with a fixed 1-3\/8\" bore and 8.0\" outer diameter. This is one of the larger motor pulleys in the Cast Air 2B fixed-bore lineup, used when the application calls for higher pump RPM — and therefore more delivered CFM — from the same motor. If your 8.0\" OD pulley is cracked, groove-worn, or damaged, this is the direct replacement.\u003c\/p\u003e\n\n\u003cp\u003e\u003cstrong\u003eNote: Cast Air did not provide a dedicated manufacturer product page for this pulley.\u003c\/strong\u003e Specifications are drawn from the product listing and standard 2B pulley conventions. Contact us to confirm fitment for your specific compressor before ordering.\u003c\/p\u003e\n\n\u003ch2\u003eWhy the 8.0\" OD Pulley?\u003c\/h2\u003e\n\u003cp\u003eMotor pulley OD controls pump speed. A larger motor pulley drives the pump faster relative to motor RPM. An 8.0\" motor pulley paired with a 14\" pump flywheel produces a drive ratio of approximately 1.75:1 — meaning a 1,750 RPM motor drives the pump at roughly 1,000 RPM. This is toward the high end of the operating range for Cast Air single-stage pumps and delivers maximum CFM from those pump designs. The 8.0\" OD is typically found on compressors where the motor is sized to handle the increased pump load and heat that comes with higher RPM operation.\u003c\/p\u003e\n\n\u003ch3\u003ePulley Specification Details\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eGroove Profile:\u003c\/strong\u003e 2B (two B-section V-belt grooves)\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eBore Type:\u003c\/strong\u003e Fixed bore — 1-3\/8\" (1.375\") shaft diameter\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eOuter Diameter (OD):\u003c\/strong\u003e 8.0\"\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eApplication:\u003c\/strong\u003e Motor-side pulley for belt-drive air compressors\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCompatibility:\u003c\/strong\u003e Castair belt-drive compressors with 1-3\/8\" motor shafts and B-section belts\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003ePart Number:\u003c\/strong\u003e P2B80-13\/8\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003eFixed Bore Identification and Installation\u003c\/h2\u003e\n\u003cp\u003eThe P2B80-13\/8 is a fixed-bore pulley. It is machined with a 1-3\/8\" center bore and includes keyway slots and set screw holes for securing to the motor shaft. Installation is straightforward: slide onto the shaft, align the key, and tighten the set screw. The important thing is confirming you have a 1-3\/8\" motor shaft — neither larger nor smaller — before ordering, because a fixed bore pulley cannot be bored out or resized in the field.\u003c\/p\u003e\n\n\u003ch3\u003eFixed Bore vs. Taper-Lock Selection\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eFixed bore (this pulley):\u003c\/strong\u003e One specific shaft size. No bushing required. Correct for direct replacement when original was also fixed bore 1-3\/8\".\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eTaper-lock (SK\/SD):\u003c\/strong\u003e Bushing-style hub adapts to multiple shaft diameters. Different installation method, different part number — not interchangeable with fixed bore.\u003c\/li\u003e\n\u003cli\u003eVerify your motor shaft diameter is exactly 1-3\/8\" before ordering this pulley.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003eWhen Does a Shop Need the 8.0\" OD Pulley?\u003c\/h2\u003e\n\u003cul\u003e\n\u003cli\u003eOriginal motor pulley measured 8.0\" OD with 1-3\/8\" bore and is worn, cracked, or damaged\u003c\/li\u003e\n\u003cli\u003eRebuilding a Cast Air compressor that came factory-equipped with an 8.0\" motor pulley\u003c\/li\u003e\n\u003cli\u003eApplication requires higher pump RPM than smaller pulleys provide and the pump\/motor combination is rated for it\u003c\/li\u003e\n\u003cli\u003eTachometer confirms pump RPM is lower than spec — a replacement pulley of the correct OD restores the original drive ratio\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003e2B Fixed-Bore 1-3\/8\" Motor Pulley Size Comparison\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eP2B625-13\/8 — 6.25\" OD — $68.34\u003c\/strong\u003e — lowest pump speed in the series\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eP2B675-13\/8 — 6.75\" OD — $71.23\u003c\/strong\u003e — standard mid-range OD\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eP2B725-11\/8 — 7.5\" OD — $84.70\u003c\/strong\u003e — larger, for increased pump RPM requirements\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eP2B80-13\/8 — 8.0\" OD — $88.55\u003c\/strong\u003e (this unit) — high-speed motor pulley for maximum CFM applications\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eP2B875-13\/8 — 8.75\" OD — $103.95\u003c\/strong\u003e — largest fixed-bore 1-3\/8\" option\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003eTechnical Specifications\u003c\/h2\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003ePart Number:\u003c\/strong\u003e P2B80-13\/8\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eManufacturer:\u003c\/strong\u003e Cast Air (Castair)\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eGroove Type:\u003c\/strong\u003e 2B (two B-section V-belt grooves)\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eBore:\u003c\/strong\u003e Fixed, 1-3\/8\" (1.375\")\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eOuter Diameter:\u003c\/strong\u003e 8.0\"\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eBore Style:\u003c\/strong\u003e Fixed (keyway and set screw)\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eBelt Section:\u003c\/strong\u003e B-section (two matched belts)\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003ePrice:\u003c\/strong\u003e $88.55\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eManufacturer Data:\u003c\/strong\u003e Product page not available — specifications from product listing data\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003eWhat Is Included\u003c\/h2\u003e\n\u003cul\u003e\n\u003cli\u003e1x Castair P2B80-13\/8 motor pulley\u003c\/li\u003e\n\u003cli\u003eSet screw(s) for shaft retention\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003eB-section matched belts are not included. Determine the correct belt length based on your drive center distance.\u003c\/p\u003e\n\n\u003ch2\u003eWhy Buy From Air Compressor Factory Direct?\u003c\/h2\u003e\n\u003cp\u003eWe have stocked Cast Air replacement parts since 2016 and carry the full motor pulley lineup across OD sizes and bore styles. If you are not certain whether 8.0\" is the correct OD for your specific compressor, call us before ordering — we can verify against your model number. Free shipping on all orders, free tech support, and full manufacturer warranty on every Cast Air part.\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eCast Air specialist\u003c\/strong\u003e since 2016\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eFree shipping\u003c\/strong\u003e on all orders\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eFree tech support\u003c\/strong\u003e — confirm fitment before you order\u003c\/li\u003e\n\u003cli\u003e\u003cstrong\u003eFull manufacturer warranty\u003c\/strong\u003e\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eHonest guidance\u003c\/strong\u003e on which OD fits your application\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003e\u003cstrong\u003eCall 866-217-0063 for quick answers and help!\u003c\/strong\u003e\u003c\/p\u003e","brand":"Cast Air","offers":[{"title":"Default Title","offer_id":53342573854933,"sku":"P2B80-13\/8","price":163.3,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0622\/8466\/0949\/files\/MOTOR-PULLEYS-300x248_7323ee7c-935d-412f-98ae-f6496e2cdf55.jpg?v=1772652776","url":"https:\/\/aircompressorfactorydirect.com\/products\/castair-replacement-motor-pulley-1-3-8-fixed-bore-shaft-8-0-od-2b-grooves","provider":"Air Compressor Factory Direct","version":"1.0","type":"link"}