Glixal ATMT1-011 139QMB 139QMA Scooter Big Bore Cylinder Kit Rebuild Kit GY6 100cc 50mm Moped ATV Go-Kart

This big bore kit works great!* I will say in advance that you should get rid of your stock carburetor and buy a new carb; I have one with an auto enrichener on it, but I am sure ANY carb that isn't stock will work great. Their stock carbs suck - get a performance carb, they aren't that expensive. *I purchased this kit because, despite following the directions for how much oil to add during the oil change, there wasn't enough oil in the engine and I ended up burning up my stock piston rings. So I figured if I am going to have to take the piston out to fix it, I might as well upgrade the thing.Got the kit. It came with all the parts. Groovy.*** It doesn't come with instructions so make sure you find some online, specifically with how the rings need to be oriented on the piston, if you don't already know. If you jack this up, it will screw with your compression and possibly let oil into to the head, which isn't good. Speaking of heads, I am using the stock head and valves with this kit and it works just fine. ***Once I got it installed (everything seemed to fit just fine), I recalibrated the valves, I added oil (the right amount this time), broke it in, changed the oil again, checked the valves again, and now everything is smooth.** I didn't seem to need to re-jet the carb despite the volume being larger, but I have heard of people doing that so look into that. **Listen, all I am going to say about speed, is that it is going to increase: you will be happy with the results, I promise.What I wanted the kit for is going uphill. I live in a place with a lot of hills so having that power to push me uphill is nice. I am a heavy dude, about 260lbs, so the output is necessary; without it, I was crawling uphill at maybe 10mph; now I am going uphill at about 25mph. It's a fairly steep grade.Final point: You WILL get the most bang for your buck with this kit. You WILL be happy with the speed. You WILL be happy with the output.

i’ve purchased this simple kit over a dozen times. installs on my personal bikes and for friends. 100% success rate. my first time i had 0 knowledge and it still started. over time i’ve learned to do the change in 40 minutes!!!! this kit won’t increase the performance of your bike the way it’s usually exaggerated. what it does do is unlocks the full power a 50cc has to offer. do you want reliability,comfort,no hassle and SPEED???? okay then buy a 150cc this kit increases temp in motor making long ride’s impossible.increases compression causing oil leaks ,rough cold starts and increased stress on motor overall. i did daily drive a bike to work (about 10 miles) 5 days a week for 2years only changing the kit once. don’t wait for it to blow i literally change my kit with every oil change it’s so cheap a huge bang for buck!!

Kit was easy to install if you want to upgrade a50cc to 100cc these work great great plus the value you pay works great

The installation was perfect! This was my first time touching an engine besides a single oil change, and it all went extremely smooth. All the parts were high quality, and fit together well. The new piston and it's rings sure are a tight fit, but tight fit makes for good compression as long as it's properly lubricated. The kit started up after only a few kicks, and I could definitely feel the increase in displacement - bassier rumble, louder engine, it almost wants to run. However, most GY6 scooters are shipped lean to prevent inadvertent engine damage and pass emissions inspections - good for fuel economy, bad when your engine is bigger than expected. There is no simple idle mixture screw fix either, since it effects the entire power curve and most Chinese scooters plug the screw. I'm gonna install the new carb tomorrow, however tonight it runs, and that's more than I can ask for a rebuilt engine that's running far too lean

The media could not be loaded. So I’ve been working on motors and stuff for a long time rebuilt plenty. This looked good when it came of everything went together fairly easily didn’t really have any problems up until yesterday at a roundabout I can’t remember 97 miles then we had catastrophic engine failure, piston, come completely detach from the rod and smash the bottom of it. Looks like it messed up my head and bent or valve or two or both, so they cost more money to fix then it’s worth

Purchased this as a replacement after accidently blowing up my first 139QMB big bore kit. Easy to install and very high quality. Make sure you don't reuse your wrist pins!!!! As long as you take your time and do your research, Glixal products will treat you very well. I've put over a thousand miles on this specific kit with absolutely no issues. Couldn't be happier!

It was my first time installing one of these and I learned a lot on what I should and shouldn’t do next time. While my scooter was working it ran great and gave it a lot of extra power but I did run into a few problems such as an oil leak. Take my advice, if it runs fine, do not take your scooter apart again to try and fix it. I did this and my scooter died and never ran again.