I've added this upgrade onto my bike it's perfect only thing I found was that the front sprocket was a little loose even with the washer. I'm hearing some noise but unsure if it's the upgrade so I can hear the chain go more now if if there's a problem. ============== Admin Reply: Thanks for your feedback, glad you love it like others do!💎 - If your font sprocket has a rattle, please investigate your drive shaft itself, we don't know if your own previous sprocket splines caused any issues to it etc, remember the original OEM sprocket from Hyosung is made in China, another owner made his bike chain adjustment too tight and he lost his engine shaft, so it was a mess! (his own fault) but the original sprocket was badly worn even inside the spline teeth connecting to the front engine shaft , so double check your setup! Remember to check chain slack and keep it lubed well!

After a little bit of a struggle I finally got the kit on! Thanks to the forum post that front sprocket was a right ass to get off! The bike feels much nicer to get up to speed, it feels a lot smoother and nicer to ride! So far I’ve noticed an increase of about 5mph on the top speed but I haven’t pushed it to see how far it will go but that extra 5mph gives a more comfortable carriageway experience. Highly reccomend!

received this item today was only posted yesterday wow i was shocked but in a good way of cause well recommended seller will be purchasing more off of this site

MARCEL ROCKS! Not only is this kit is a must have upgrade for your bike, but the support and advice i've got from Marcel is amazing! You should now that this is my first motorcycle and I really love to make my hands dirty. I love my bike but the acceleration was a bit disappointing. I've read about a tooth more or less on the front or back sprocket, but i really didn't wanted to loose any top speed. It seemed to be one or the other (more acceleration more top speed). I talked to my dealer about this, but I didn't find any help there. So I contacted Marcel. He sent me the kit and the delivery was very fast (I live in Belgium) Then came the moment of truth: would I be able to do the upgrade myself? I succeeded with easy with some remote support from Marcel over messenger. His reaction time was very fast and I didn't loose time with the procedure if i had a question. Many thanks for that Marcel. The day after the installation came the second moment of truth. Would this upgrade perform as advertised? In short: IT DID! The test ride with these sprockets / chain exceeded my expectations . The acceleration in gears 1-4 is superb now. In second gear i can pull up to 50km/h - in 3th to 70 km/h without going in the red range! The bike pulls really fast now. About the top speed, with original chain kit my top speed was 107km/h on a steep downhill. Now on a far less steep one i reached 119 on display and gps speed was 107 !!! Speed record easily broken.

Where do I start? The beginning I guess 😉 I bought this Beauty, a GV125-S last Month and was not happy with the Power and acceleration, or should I say missing Power of the 14 PS compared to my last ride a Yamaha XV 125 with 11 PS. Dont get me wrong I noticed the difference, but she was just laggy, screaming at me, and the Vibrations when going above 8000 Revs. In 5th gear she hit 10-11000 revs and just stopped power wise, not going any faster than 105 Km/h on the dial. In the German Group on Facebook it was suggested to upgrade the front Sprocket to one with 15 teeth, which I did, She run a little smoother through the Gears and the Engine sounded a bit quieter and wasnt screaming at me, but the loss in Power in the lower Gears, especially going from 2nd to 3rd, and the Top speed of 110 Km/h, which took me ages to get there, wasnt satisfactory, taking her up into the Red again to get here.. Then I saw Marcels post in that Group and decided to buy this Upgrade from the UK and have it shipped to Germany, thanks to Marcel here for the support. What can I say? I took her out on a 3 Hour ride to test, what a difference! The smaller front Sprocket (13) and the Larger Rear Sprocket (Dimension) and 520 Chain is the perfect combination. She shoots up through the Gears, no Jerking, no screaming Engine, next to no Vibrations, just smooth and fast, at 9-10000 Revs in 4th Gear she hits 100 Km/h and in 5th I had her at 120 Km/h and felt like there was still more .... plus it was a windy day 😉 I also ordered the NGK Spark plugs and HT leads which just finishes off a perfect combination. Thanks Marcel and Team, Season nears its end and I just cant wait to get out there next year, the Bike is so much fun now and I dont miss my Yamaha at all 😉

Installed to my Hyosung GT125R, immediately noticed the dashboard lights are much brighter, the head lamp is brighter, it starts quicker and generally feels a lot smoother to ride. Cannot recommend it enough. Thank you. 🙏