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GY6 Cylinder Rebuild Kits Trkimal Upgrade 50mm Big Bore Kit Cylinder head assemble 69mm valve sets for 49CC 50CC 139QMB Moped Scooter Engine, Racing Performance CDI Ignition Coil Spark Plug Clutch etc

Free shipping on orders over $29.99

$79.97

$ 37 .99 $37.99

In Stock

1.Size:64mm Valve Length


  • 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
  • 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
  • Simple Installation
  • Upgrades parts kits for most of 50cc scooter


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


Snakes
Reviewed in the United Kingdom on June 12, 2024
since the cylinder head was fitted had nothing but problems. first cdi unit did,nt work so bout a new one which kinda worked. then 4 weeks later the cylinder head packed in exhaust valve blown along with the spark plug electroid which caused engine to cut and lock up
Mary luz Aguilera
Reviewed in Mexico on January 11, 2024
Lo que yo esperaba
Nicholas
Reviewed in the United States on June 14, 2023
Okay so I have only had it in for about a day but I can tell you that it DOES increase your power. If you install this kit make sure to get the 69mm valve length version as it is the same price and allows for more air and exhaust flow. Since this kit comes with the head and cylinder you dont need to worry about having the "wrong" valve length because the piston and cylinder are matched to the head. Also, when you put this kit on your engine, make sure to time it correctly, adjust the valve clearance correctly, and make sure to readjust the timing chain tensioner when you put it back in. Look up videos on youtube if you dont know how to do those because you will need to know how if you want to put this kit on. This kit comes with lighter than stock roller weights for the variator and stiffer clutch spring, which will overall give you an increase in acceleration but decrease your top achievable speed should you choose to put it in. I chose to lesve mine stock because i can comfortably get up to 45 mph and maintain that speed even going up a hill or steep incline. This kit also comes with a new oil pump, which is not necessary to put in as it is the same volume output as the stock one, so basically it can be a spare if you want or you could put it in the engine anyway since it wont hurt. For those attempting to install this kit themselves, make sure you apply a thin layer of oil on all the parts as you slide them into place in the cylinder and head. That means, apply a small layer of oil to the piston and rings to get it into the cylinder easier, and also apply a little oil to the camshaft lobes and rocker contact points and a little to the timing gears and chain. Basically any of the moving parts. You don't want to get premature wear when you kick the engine over the first time. Check the valves in the head before installation to make sure they seal properly too, i did this by pouring alchohol in the intake and exhaust ports while the valves are closed and seeing if they leak. This is crucial stuff to know when doing a kit like this and there is no instruction manual so if you are not mechanically inclined or dont know what anything ive mentioned is then do some research before ordering this as it would be quite the headache to put it all together and then have it not run. Lastly, if you plan to use this kit to rebuild your engine, I would highly suggest getting bigger jets for your carburetor or a new high perfornance carburetor with bigger jets and making sure you retune the air/fuel mixture and idle screws regardless of whether you replace the carburetor to make sure that the engine gets the right amount of fuel for the bigger displacement. All in all great kit! If I haven't updated this review or posted another one yet that that means it's still running strong and I've had no issues. Highly recommend!
Will V.
Reviewed in the United States on March 14, 2023
Wouldnt suggests putting the coil on. It made it run really badly. Gaskets are cheap but do work. you get what you pay for
Jason
Reviewed in the United States on August 23, 2022
Update 2: still going strong 800 km. Very happy. Very easy.Update: been a couple weeks and 200 km. Running strong still. Very happy! Reasonable max speed is 45mph at about 4500rpm. Seen 50 with tucking. Main benefit is acceleration not so much top end.Carb settings are fussy when using original. Tends to stall sometimes off idle. Working on jetting for mid range.Original post: Got the scooter free and been playing at getting it running. Had it tuned well, fully stock with a slightly larger jet (original main was 75 and I took it to 85). Ran well but took 30 sec or so to get to 30 mph and with a long run on flats I could reasonably expect 42mph. Hills of any sort knocked it back to 30 pretty quickly. My point is it was running well stock.Installed this kit (just the jug, head, cam, rockers) and took it for a test ride... WOW. WORTH IT! (Buy the 69mm since its the complete kit anyhow.)I'm still in break in period so I've not done any full speed tests... seat is still off so I can tune. I sit on the tank for testing. It will wheelie!It actually pulls when gassed. Acceleration is substantially improved. Been to 40mph and its still pulling strong with more to give. 0-30mph is no longer a concern for pulling out in traffic.Carb needs a bit of fussing with idle, idle mix and mid jet but so far nothing more that what one might do in spring.Will update if any issues.This has taken the broken free scooter from marginally entertaining neighborhood tour scoot to something I might venture out onto roads with a speed limit above 35mph... possibly short stints on 45! I'm certain it will hit 45 without tucking and I'm 230lbs.Best and near cheapest mod yet.Install from plastic removal to test running was about 3 hrs. Only special tools, a torque wrench for head bolts and a feeler guage for valve setting. Even ring end gap was to spec out of the box.Its no sport bike but now its a bit of a grocery getter.
Patrick
Reviewed in the United States on June 6, 2021
Because it is essentially a generic upgrade it has gaskets that in most cases you won't even use depending on your application. This is a nice touch since too often many of these types of kits come up short. There isn't much that can be more frustrating than getting half way or better through a project only to realize that it was missing gaskets, or specific bolts, nuts, or components. Then having to put your project on hold and wait for the part you needed to begin with.There is an option for 64mm or 69mm valves. Let me take the confusion out of which you should get. Because this kit comes with everything you will need to complete the job, you can pick whichever you feel you want to go with. If you were going to re-use your own rocker arms, then you would need to know which length valves you have. If you use everything provided there would be no concern if your previous build had 64mm and you ordered a 69mm kit.The only reason to really be concerned about which valve length to get with this kit, is if you plan to port and polish the intake and exhaust on the head. The 64mm does not have much of a wall thickness to begin with. If you start trying to port the 64mm head you will run out of material fast and blow right through the wall into the valve train compartment.Look up the differences on 64mm and 69mm on 49ccscoot com, he does a very in depth explanation of the difference.The only thing that could make this kit any more complete is if it included a larger carb to accommodate the larger displacement you are installing. My suggestion, get yourself a nice carb kit for a GY6 150cc instead of tinkering around with jets to make the existing carb work.