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STG 50mm Big Valve Performance Head for 100cc 139QMB and GY6 Scooter Engines

$ 21.11

Availability: 26 in stock
  • California Prop 65 Warning: California Prop 65 Warning Applies
  • Returns Accepted: ReturnsNotAccepted
  • Warranty: Yes
  • Manufacturer Part Number: Does Not Apply
  • Brand: STG
  • Condition: New
  • Part Brand: STG

    Description

    STG Big Valve Performance Head
    for
    50cc to 100cc engines -
    139QMB and GY6
    ***United States supplier. Shipping from Grand Rapids, Michigan. Ships via USPS Priority Mail. ***
    ***Most orders have same day shipping, and arrive within 2-3 business days!***
    83cc - STG Big Valve Performance Head
    for 50cc to 100cc 4-stroke engines - 139QMB and GY6
    Includes: 50mm Cylinder Head, Head Stud Hardware, Rocker Arm Assembly, and Head Gasket.
    What's Included & Specifications
    Big Valve Head
    Cylinder Head
    -50mm aluminum cylinder head with oversized valves
    -69mm valve length w/ corresponding rocker assembly
    -Dish Diameter- 50mm
    Rocker Arm Assembly
    -Aluminum Rocker Arm Assembly (for 69mm valve length)
    Gasket Set
    -All of the required gaskets to install this kit
    What is the difference between the 100cc kits and the 83cc kits?
    The 100cc and 83cc kits have the same piston diameter (50mm), but the both kits actually only produce 83cc's. Kits that claim to be 100cc's are not actually 100cc's, so this is the first warning sign when trying to avoid inferior big bore kits. Kits that claim to be the true 83cc's have nothing to hide, and often are of higher quality than the "100cc" kits.
    What separates these big bore kits from all the other kits you see online?
    These are the same cylinder heads that Scooters To Go has been using on their racing engines for years, and they are the only kits that Scooters To Go trusts when building a high performance machine. The STG Performance 50mm Big Valve Cylinder Head also functions as the ultimate performance upgrade if you already have a big bore kit installed. This cylinder head provides better air flow for both the intake and exhaust valve, because if its increased valve diameter. Because of this better air flow, more power can be produced, and the internal temperature of your engine can stay cooler.
    Other recommended upgrades that pair well with this head include:
    STG 20mm Carburetor
    A9 Camshaft
    50mm Airsal Piston
    49/17 Gears (pre-pressed for easy install)
    What can customer's expect out of this setup?
    With this setup, customers can expect to see a dramatic increase in throttle response, acceleration, and top speed. With the proper clutching, carburetor jetting, and gearing, these kits are easily capable of speeds between 50 MPH and 55 MPH.
    How long do these kits last?
    If customer's change their oil regularly with the STG recommended oil, they can expect between 10,000 km and 15,000 km out of these parts.
    Don't fall victim to some of the other kits sold online, you may save a few dollars on your initial purchase, but soon after, parts will need to be replaced due to poor manufacturing and cheap product materials. Scooters To Go has been using these performance big bore kits and camshafts for years in their 87cc racing engines, and they are the only parts they trust. Scooters To Go trusts these performance big bore kit so much that they come with a 30-day (unlimited mile) warranty against product failure*.
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    *30-day (unlimited mile) warranty does not cover product failures that result from improper customer installation, improper air/fuel ratio tuning, failures that result from other engine component failures, engines exceeding 8500 rpm's, improper oil servicing, or foreign object ingestion. If a customer experiences a product failure, the component must be shipped to Scooters To Go, at the customer's expense, for quality assurance and verification purposes.
    If you have any questions, comments, or concerns about this product, our warranty information, or our returns policy, feel free to message us via eBay, reach us through Facebook, or call us @ 877-569-5691.