Installed on RC 2018. This will be longer than most reviews but want to get all the details down to help you guys decide. Ladies and gents, the big ticket item on here for the GT family. If you enjoy performance and speed, then my god is it worth it. The damping and preload makes bumps and crests effortless, no bottoming out and chain is free to do it's thing. I have managed to test it here in Ulster on the road race tracks (not when closed roads sadly) and it performed like a dream, ride flows from section to section, cornering is massively improved, I can't fault it. Adjustment is relatively simple, I'm 85kg/6 ft4 so some adjustment/firming was needed out of the box, but all very straightforward, plus a higher set ride height is noticeable for me. Installation is one for one with OEM, would recommend mechanic there to give the bones and links a once over/lubrication and for an extra pair of hands. It is a larger price tag, but it's not everyday we get a company like YSS making a specific product for Hyo's. If you are on the fence, then definitely go for it.

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 😉

Got a set for my project bike a 12 front 48 rear on my xrx125 and it has made a lot of difference to the way the bike rides, it's not a gear setup I got for top speed I wanted more acceleration so went with a 12/48 set up now the bike not only holds it's top speed but I am able to go up hills or against head winds without changing down a gear, I can even accelerate up hills and change up gears that a normal 125 would struggle with. Apart from the way it helps the bike run, the look of the new setup is so much better than the stock setup. I can't say how long it will last as only done a couple hundred miles, so far it looks good. It's a simple upgrade that's worth the money

It really does make big difference I’m just not sure about the front sprocket Because I see the one on shop it has 14teeth I recited 13teeth But I’m very happy about this upgrade Thanks Marcel

Bought and Installed on RC 2018. Excellent strength, the full kit that is provided is excellent value for money and much better than other providers. Sprocket especially is a great upgrade. Visually it looks great, I will aim to get some photos added to show final product.

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!