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KYMLAA

GY6 Cylinder Rebuild Kits Kymlaa 100cc Big Bore Kit for 69mm Valve 49CC 50CC 139QMB Moped Scooter Engine 50mm Bore Upgrade Set with 6pin Racing CDI Ignition Coil Performance Spark Plug Clutch Spring

    • Based on 181 reviews
Condition: New
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$79.97 Why this price?

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Availability: In Stock.
Fulfilled by Amazon
Arrives Sunday, May 19
Order within 22 hours and 41 minutes
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Features

  • This big cylinder kit will upgrade your gy6 50cc 60cc 80cc to 100cc, without EGR, to get more RPM,more power, faster maximum speed.
  • 69mm valve length version
  • Simple Installation
  • With cylinder body kits, cylinder head kits, camshaft, camshaft seat kits, gaskets kits, oil pump and gear, spring sets, copper roller sets, 6pins racing AC CDI, ignition coil and racing 3-electrode spark plug
  • Upgrades parts kits for most of 50cc scooter

Description

Size:69mm Valve Length Fitment: Jonway 49cc 50cc 4 stroke scooters like warrior 50 50cc 4 stroke like Agility 50,People S50 4T,Suer 8 50 4T Pagsta mini 49cc Baja 49cc 50cc 4stroke scooters like motorsports SC-50 sun city,primo,DR50,Dirt Runner 49 Baotian BT49QT-2,BT49QT-7,BT49QT-9,BT50QT-9,BT50QT-11 Dotera 50QT-11 Eton 49cc 50cc 4stroke like Sport 50 Fly 49cc 50cc 4-stroke scooters Jalon JL50QT-15,JL50QT-16,JL50QT-18,JL50QT-21,JL50QT-21 Falcon. Jinlun 49cc 50cc 4-stroke scooters Roketa 49cc 50cc 4 stroke scooter such Bahama,Maui,Sicily,Tank,Baotian 50QT-9 Sinski XSJ50QT-6, XSJ50QT-B SSR Lazer 5 Moped Sunl SL50QT-16, SL50QT-18,SL50QT-2,SL50QT-3 Tank 49cc 50cc 4-stroke scooters Taotao 49cc 50cc 4 stroke scooter such as GT5,Fastwind,AMT50-A1,CY50-A,CY50-B,CY50-T3,Funny50,Roman 50,Retro 50,Speedy50,Venus50 Verucci VC50TS-3M VIP future champion 4 stroke Zhong Hu 50cc,Zongshen Metro 50cc Zongshen ZS50QT-4 Many more GY6 4-stroke 49cc 50cc 60cc 80cc from china. engine Specifications: Bore: 50mm Displacement:100cc Valve Length: 69mm Pacakage Included: 1 x Set of 6 Gram Racing Pure Copper Roller Weights 1 x Cylinder Head with 69mm valve with Update Camshaft. 1 x Rocker Arms Assembly 2 x Valve Seals 1 x Oil Pump Assy with Driving Gear 1 x 50mm Bore Cylinder Block 1 x Set of 50mm Piston Assy, Piston, Rings and Wrist Pin 1 x Full Set of Engine Gasket 1 x Set of Intake Manifold and Muffler Bolts, and Exhaust locking hat 1 x 6pins Racing AC CDI 1 x Racing Ignition Coil 1 x Racing 3-electrode A7TC Spark Plug 1 x Set of Clutch Small Racing Spring 1 x Racing Clutch Big Spring

Manufacturer: ‎KYMLAA


Brand: ‎KYMLAA


Item Weight: ‎6.6 pounds


Package Dimensions: ‎10.31 x 7.24 x 6.18 inches


Manufacturer Part Number: ‎KYMLAA-00050-1


Date First Available: September 24, 2019


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Sunday, May 19

Yes, absolutely! You may return this product for a full refund within 30 days of receiving it.

To initiate a return, please visit our Returns Center.

View our full returns policy here.

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Leasing options through Acima may also be available during checkout.

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Top Amazon Reviews

    • Works really good
Review Image by Michael Michael
Review Image by Michael Michael
Review Image by Michael Michael
I ended up buying this because I had lost compression in my 50 cc moped and this was definitely an upgrade has a lot more compression now anyone that put a bad review on this didn’t install it right I can understand missing parts but other than that take your time on it. It only took me 30 minutes.
Reviewed in the United States on February 19, 2024 by Michael Michael
    • Perfect fit. Perfect install. Way better power. Great product for the price.
Review Image by Amazon Customer Amazon Customer
Review Image by Amazon Customer Amazon Customer
If there is a single bad review on this item it was either a fluke or lack of installer experience. This kit came exactly as shown. Was very easy to install, and took 2 hours total and wasn't even rushing. Watch a few YouTube videos and DO NOT RUSH! Everything went together perfect, and smooth. All parts including exhaust studs were absolutely fine and same as stock. Bike started up within a few cranks once gas got back in to the carb. The power is night and day. Have no problem getting my tao 50 pony up to 40-45mph now, and quickly. Pulls wheelies fairly easily now as well. Literally was getting smoked by my buddies mopeds earlier in the day, and went back to his house after install and put bus lengths on his 2 stroke moped. Much more responsive. Keep in mind I already had an upgraded jet (85) and intake and exhaust and a 7/5gram split slider swap. But literally runs perfect as is with only a small idle adjustment. Highly suggest this kit. I haven't even installed the cdi, clutch springs, or big main engine gaskets either. Only complaint I have is the spark plugs that keep coming with these kits and the cdi kits are trash. Use ur stock plug or a new stock one. Other then that we'll worth the money and definitely a good buy. ... show more
Reviewed in the United States on September 4, 2023 by Amazon Customer Amazon Customer
    • Works great!
After watching a few YouTube videos, the installation went perfect on my GY6 139QMB. I mated it up with a 125cc carburetor here from Amazon, and even before jetting the bike started up and ran smoothly. Before jetting and adding in the new clutch springs and variator rollers, I'm seeing an easy 5-8 mph increase. So far, I've hit 42 mph on GPS, flat ground. Still need to fine tune the jet size, add the included clutch springs, rollers, and then lastly obtain a new final drive setup to get the most top end power. See "Rolling Wrench" on YouTube for great instructional GY6 videos. ... show more
Reviewed in the United States on April 23, 2022 by Blake
    • Nice. Some missing parts
The kit is nice put it didnt came with the oil pump and New spark plug. But love 100cc on my scooter.
Reviewed in the United States on February 1, 2020 by Kristjan
    • Rebuild kit
Kit was not good .. the rings locked up and piston scared the rings on a customers machine .. wished I’d had not been so cheap and bought a good one
Reviewed in the United States on October 23, 2023 by Dewayne(Crash)Whitner
    • 100cc 50mm kit
This kit had everything you needed.very happy with.
Reviewed in the United States on August 12, 2023 by Christopher Paul Voss
    • I love the big bore kit.
Gives you a lot more kick. accelerates good and once everything is worn in it rips pretty good. you need to know how to work on an engine to install this, but there are enough youtube videos to show how to do a big bore on one of these.
Reviewed in the United States on October 22, 2022 by Alex M.
    • Not worth the effort to install for what little HP it puts out
I'd like to say that this 100cc kit comes with absolutely everything you'll need to convert your 50cc scooter to a 100cc scooter other then a upgraded carburetor. The seller also communicates very good with buyers regarding product isues. Installation of this 100cc kit was not simple it took me a good solid day to install it on my scooter and found out that one the gaskets was defective cuasing a major oil leak so I had to order new gasket set and redo the whole job again. My little scooter defintly has a little more 'pep' to it now then it did before but not of a huge amount that makes a big difference in my opinion. It almost feels like its an 80cc instead of a 100cc as the kit claims to be. In my opinion installing this kit onto my scooter wasn't worth the cost or the effort to do it for such a little horsepower gain. Its not a bad kit and it does give some horsepower gain but just not allot that makes it worth doing in my opinion. ... show more
Reviewed in the United States on July 2, 2022 by BS

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