{"product_id":"40-flat-chain-drive-sprocket-10t-37t-pitch-1-2-12-7mm-for-40-08b-roller-chain","title":"#40 Flat Chain Drive Sprocket 10T-37T Pitch 1\/2\" 12.7mm For #40 08B Roller Chain","description":"\u003cdiv class=\"hdiy-desc\"\u003e\n\u003cdiv class=\"hdiy-overview\"\u003e\n\u003ch2\u003e#40 Roller Chain Sprocket — Precision-Machined Drive Wheel for #40 \u0026amp; 08B Chain Systems\u003c\/h2\u003e\n\u003cp\u003eWhen a worn or undersized sprocket causes chain skip, premature wear, or misalignment in your drive system, the fix starts with a correctly matched wheel. Whether you are building a go-kart drivetrain, retrofitting a conveyor, or replacing a worn component on a mini-bike or small engine application, the right tooth count and pitch are non-negotiable. This #40 flat chain drive sprocket is engineered for makers, fabricators, and mechanical hobbyists who need a reliable, drop-in replacement or new-build component without guesswork.\u003c\/p\u003e\n\u003cp\u003eEach sprocket is machined to ANSI #40 \/ ISO 08B chain standards with a pitch of 1\/2\" (12.7 mm). The flat-plate hub design keeps the profile compact and the bore concentric. Available in 10T through 37T configurations, outer diameter scales from approximately 42 mm (1.65 in) at 10T to approximately 150 mm (5.91 in) at 37T. Bore diameter and keyway dimensions vary by tooth count — see variant options for exact bore specs.\u003c\/p\u003e\n\u003cp\u003eTypical use cases include go-kart and mini-bike final-drive replacement, small conveyor and feeder drive systems, DIY robotics and automation chain loops, and light agricultural equipment sprocket swaps. Long-tail search terms that describe this product: #40 chain sprocket 10 tooth replacement, 08B roller chain drive wheel 37T, 12.7mm pitch flat sprocket for go-kart.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"hdiy-compat\"\u003e\n\u003cspan class=\"hdiy-compat-icon\"\u003e🔗\u003c\/span\u003e \u003cstrong\u003eCompatible Chain Standards:\u003c\/strong\u003e ANSI #40 Roller Chain  |  ISO 08B Roller Chain  |  Pitch: 1\/2\" (12.7 mm)\u003c\/div\u003e\n\u003ch2\u003e✅ Key Features of These #40 Roller Chain Sprockets\u003c\/h2\u003e\n\u003cdiv class=\"hdiy-features\"\u003e\n\u003cdiv\u003e\n\u003cdiv class=\"hdiy-icon\"\u003e⚙️\u003c\/div\u003e\n\u003cstrong\u003eANSI #40 \/ ISO 08B Dual Standard\u003c\/strong\u003e\n\u003cp\u003eMachined to both ANSI #40 and ISO 08B chain pitch specifications, ensuring interchangeability across North American and metric roller chain systems without adapters.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv\u003e\n\u003cdiv class=\"hdiy-icon\"\u003e📐\u003c\/div\u003e\n\u003cstrong\u003eWide Tooth-Count Range: 10T to 37T\u003c\/strong\u003e\n\u003cp\u003eTwenty-eight tooth-count options in a single product listing let you dial in your exact gear ratio — from fast, low-torque 10T configurations to high-torque 37T setups — all sharing the same 1\/2\" pitch.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv\u003e\n\u003cdiv class=\"hdiy-icon\"\u003e🔩\u003c\/div\u003e\n\u003cstrong\u003eFlat-Hub Plate Design\u003c\/strong\u003e\n\u003cp\u003eThe flat (non-flanged) hub keeps axial clearance minimal and simplifies alignment on shafts where a stepped or flanged hub would interfere with adjacent components or frame rails.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv\u003e\n\u003cdiv class=\"hdiy-icon\"\u003e🛡️\u003c\/div\u003e\n\u003cstrong\u003eCorrosion-Resistant Surface Treatment\u003c\/strong\u003e\n\u003cp\u003eEach sprocket receives a protective surface finish to resist oxidation in workshop and light outdoor environments, extending service life between maintenance intervals.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv\u003e\n\u003cdiv class=\"hdiy-icon\"\u003e🎯\u003c\/div\u003e\n\u003cstrong\u003eConcentric Bore for True Running\u003c\/strong\u003e\n\u003cp\u003ePrecision-bored center hole ensures the sprocket runs true on the shaft, reducing vibration, chain side-load, and bearing wear — critical for high-cycle or high-speed drive applications.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv\u003e\n\u003cdiv class=\"hdiy-icon\"\u003e🔄\u003c\/div\u003e\n\u003cstrong\u003eDrop-In Replacement Geometry\u003c\/strong\u003e\n\u003cp\u003eTooth profile follows standard ANSI #40 involute geometry, making these sprockets direct replacements for OEM wheels on go-karts, mini-bikes, conveyors, and small engine equipment without chain modification.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003ch2\u003e📐 Technical Specifications — #40 Roller Chain Sprocket\u003c\/h2\u003e\n\u003cdiv class=\"hdiy-table-wrap\"\u003e\n\u003ctable\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003cth\u003eChain Standard\u003c\/th\u003e\n\u003ctd\u003eANSI #40 \/ ISO 08B\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003ePitch\u003c\/th\u003e\n\u003ctd\u003e1\/2\" (12.7 mm)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eTooth Count Range\u003c\/th\u003e\n\u003ctd\u003e10T – 37T (select variant)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eHub Style\u003c\/th\u003e\n\u003ctd\u003eFlat plate (no flange)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eOuter Diameter\u003c\/th\u003e\n\u003ctd\u003eSee variant options\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eBore Diameter\u003c\/th\u003e\n\u003ctd\u003eSee variant options\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eKeyway\u003c\/th\u003e\n\u003ctd\u003eSee variant options\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eMaterial\u003c\/th\u003e\n\u003ctd\u003eCarbon steel\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eSurface Finish\u003c\/th\u003e\n\u003ctd\u003eOxidation-resistant protective coating\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eTooth Profile\u003c\/th\u003e\n\u003ctd\u003eANSI #40 standard involute\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eWeight\u003c\/th\u003e\n\u003ctd\u003eSee variant options\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eMounting\u003c\/th\u003e\n\u003ctd\u003eSet screw or interference fit (see variant options)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"hdiy-faq\"\u003e\n\u003ch2\u003e❓ Frequently Asked Questions\u003c\/h2\u003e\n\u003cdetails\u003e\n\u003csummary\u003eHow do I know which tooth count to choose for my application?\u003c\/summary\u003e\n\u003cdiv class=\"hdiy-faq-body\"\u003e\n\u003cp\u003eTooth count determines your drive ratio. Divide the driven sprocket teeth by the drive sprocket teeth to get the reduction ratio. For example, a 10T drive sprocket paired with a 37T driven sprocket gives a 3.7:1 reduction — more torque, less speed. For go-karts, a 10T–12T driver with a 60T–72T rear wheel sprocket is common. For conveyors, match the existing tooth count on the shaft you are replacing.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/details\u003e\n\u003cdetails\u003e\n\u003csummary\u003eWill this sprocket fit my existing #40 roller chain?\u003c\/summary\u003e\n\u003cdiv class=\"hdiy-faq-body\"\u003e\n\u003cp\u003eYes. Any sprocket in this listing is machined to ANSI #40 \/ ISO 08B pitch (1\/2\" \/ 12.7 mm). As long as your chain is stamped or rated #40 or 08B, the tooth engagement will be correct. If you are unsure, measure the distance between three consecutive chain pins — it should be 25.4 mm (1.00\") for two pitches.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/details\u003e\n\u003cdetails\u003e\n\u003csummary\u003eWhat bore size does each tooth-count variant have?\u003c\/summary\u003e\n\u003cdiv class=\"hdiy-faq-body\"\u003e\n\u003cp\u003eBore diameter increases with tooth count to maintain structural integrity at larger diameters. Exact bore dimensions are listed in the variant detail page for each tooth count. If you need a specific bore size that does not match a listed variant, contact us to confirm availability of custom-bored options.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/details\u003e\n\u003cdetails\u003e\n\u003csummary\u003eIs this sprocket strong enough for go-kart or mini-bike use?\u003c\/summary\u003e\n\u003cdiv class=\"hdiy-faq-body\"\u003e\n\u003cp\u003eThese sprockets are manufactured from carbon steel and are suitable for the torque and speed loads typical of recreational go-karts and mini-bikes running #40 chain. For racing applications with sustained high RPM or shock loads, verify the bore and set-screw engagement against your shaft diameter and engine output before ordering.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/details\u003e\n\u003cdetails\u003e\n\u003csummary\u003eHow do I prevent rust on the sprocket?\u003c\/summary\u003e\n\u003cdiv class=\"hdiy-faq-body\"\u003e\n\u003cp\u003eThe sprocket ships with a protective surface coating. For extended outdoor or humid-environment use, apply a light coat of chain lubricant or anti-rust spray to all exposed surfaces. Regular chain lubrication also protects the tooth flanks from corrosive wear. Avoid prolonged submersion in water or exposure to salt spray without additional protective treatment.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/details\u003e\n\u003cdetails\u003e\n\u003csummary\u003eCan I use this sprocket with ISO 08B chain from a metric system?\u003c\/summary\u003e\n\u003cdiv class=\"hdiy-faq-body\"\u003e\n\u003cp\u003eYes. ANSI #40 and ISO 08B share the same 12.7 mm pitch and are functionally interchangeable in most drive configurations. The roller diameter and inner link plate dimensions are nearly identical, so an 08B chain will seat correctly on these #40-spec sprocket teeth.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/details\u003e\n\u003cdetails\u003e\n\u003csummary\u003eWhat is the difference between a flat sprocket and a flanged sprocket?\u003c\/summary\u003e\n\u003cdiv class=\"hdiy-faq-body\"\u003e\n\u003cp\u003eA flat (plate-hub) sprocket has a uniform thickness across the hub and tooth area with no raised collar. This keeps the overall width narrow and is ideal when axial space is limited or when the chain is guided by other means. A flanged sprocket has a raised rim on one or both sides to help retain the chain laterally — useful on applications with vibration or where the chain may wander. This listing is for flat-hub sprockets.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/details\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"hdiy-cta\"\u003e🛒 Select your sprocket tooth count above, then add to cart.\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cp\u003e \u003c\/p\u003e","brand":"HomeDIYer","offers":[{"title":"#40-10T","offer_id":52423299825938,"sku":"GF2632A-0","price":5.58,"currency_code":"USD","in_stock":true},{"title":"#40-11T","offer_id":52423299858706,"sku":"GF2632A-1","price":6.84,"currency_code":"USD","in_stock":true},{"title":"#40-12T","offer_id":52423299891474,"sku":"GF2632A-2","price":7.36,"currency_code":"USD","in_stock":true},{"title":"#40-13T","offer_id":52423299924242,"sku":"GF2632A-3","price":8.04,"currency_code":"USD","in_stock":true},{"title":"#40-14T","offer_id":52423299957010,"sku":"GF2632A-4","price":8.7,"currency_code":"USD","in_stock":true},{"title":"#40-15T","offer_id":52423299989778,"sku":"GF2632A-5","price":9.83,"currency_code":"USD","in_stock":true},{"title":"#40-16T","offer_id":52423300022546,"sku":"GF2632A-6","price":11.18,"currency_code":"USD","in_stock":true},{"title":"#40-17T","offer_id":52423300055314,"sku":"GF2632A-7","price":12.96,"currency_code":"USD","in_stock":true},{"title":"#40-18T","offer_id":52423300088082,"sku":"GF2632A-8","price":14.52,"currency_code":"USD","in_stock":true},{"title":"#40-19T","offer_id":52423300120850,"sku":"GF2632A-9","price":16.55,"currency_code":"USD","in_stock":true},{"title":"#40-20T","offer_id":52423300153618,"sku":"GF2632A-10","price":18.32,"currency_code":"USD","in_stock":true},{"title":"#40-21T","offer_id":52423300186386,"sku":"GF2632A-11","price":19.65,"currency_code":"USD","in_stock":true},{"title":"#40-22T","offer_id":52423300219154,"sku":"GF2632A-12","price":21.03,"currency_code":"USD","in_stock":true},{"title":"#40-23T","offer_id":52423300251922,"sku":"GF2632A-13","price":22.81,"currency_code":"USD","in_stock":true},{"title":"#40-24T","offer_id":52423300284690,"sku":"GF2632A-14","price":25.94,"currency_code":"USD","in_stock":true},{"title":"#40-25T","offer_id":52423300317458,"sku":"GF2632A-15","price":28.42,"currency_code":"USD","in_stock":true},{"title":"#40-26T","offer_id":52423300350226,"sku":"GF2632A-16","price":30.41,"currency_code":"USD","in_stock":true},{"title":"#40-27T","offer_id":52423300382994,"sku":"GF2632A-17","price":32.2,"currency_code":"USD","in_stock":true},{"title":"#40-28T","offer_id":52423300415762,"sku":"GF2632A-18","price":33.55,"currency_code":"USD","in_stock":true},{"title":"#40-29T","offer_id":52423300448530,"sku":"GF2632A-19","price":34.91,"currency_code":"USD","in_stock":true},{"title":"#40-30T","offer_id":52423300481298,"sku":"GF2632A-20","price":36.45,"currency_code":"USD","in_stock":true},{"title":"#40-31T","offer_id":52423300514066,"sku":"GF2632A-21","price":38.91,"currency_code":"USD","in_stock":true},{"title":"#40-32T","offer_id":52423300546834,"sku":"GF2632A-22","price":40.94,"currency_code":"USD","in_stock":true},{"title":"#40-33T","offer_id":52423300579602,"sku":"GF2632A-23","price":44.08,"currency_code":"USD","in_stock":true},{"title":"#40-34T","offer_id":52423300612370,"sku":"GF2632A-24","price":45.63,"currency_code":"USD","in_stock":true},{"title":"#40-35T","offer_id":52423300645138,"sku":"GF2632A-25","price":49.87,"currency_code":"USD","in_stock":true},{"title":"#40-36T","offer_id":52423300677906,"sku":"GF2632A-26","price":53.72,"currency_code":"USD","in_stock":true},{"title":"#40-37T","offer_id":52423300710674,"sku":"GF2632A-27","price":59.95,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0884\/8936\/1682\/files\/Picture1of4_93fdf7e7-92a5-4a52-85f5-d16bece11e1f.jpg?v=1782732449","url":"https:\/\/homediyer.com\/products\/40-flat-chain-drive-sprocket-10t-37t-pitch-1-2-12-7mm-for-40-08b-roller-chain","provider":"HomeDIYer","version":"1.0","type":"link"}