The best upgrade you can make on this bike. Those sprockets change everything - acceleration, higher max speed, better rmp/speed ratio. I'm super happy and I'd do it again, anytime. The only suggestion to Marcel I'd have is to offer the front sprocket with rubber to make the chain work quieter with less vibrations. All the rest, 10/10!

Installed on RC 2018. Wing mirrors are excellent, exact replacement for the originals. Still maintain that sporty, angular look, as much as you can with bike mirrors. Service excellent as always from Marcel/Hyo riders team.

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.

Wow such a huge difference, finally changed this myself. Not too scary. Straight swap for old kit. Didn't even need a gasket. Much sharper gear changes and acceleration. I highly recommend. On a scale of 1 to 10 it's about a 6 in mechanical knowledge. Remember to soak the plates and don't over tighten the bolts. It's a full oil change so have at least 2 litres handy

Chain worked well for a few months, had 85mph on flat, compared to normally 65, however it's been roughly 3 months and now the chain isn't holding between rides, tightened it and became slack at the end of the same ride, resorting to a max of 65 down hill, have taken 2 links out and tighten with chain slacking still got the same problem, not impressed by the quality of the chain, in total I've done less than 600 miles on this chain. Admin Edit = Customer bought kit in July 2026 and reviewed in September 2026 ,we are waiting to hear from customer about their bike configuration at the rear end (if badly worn cush drive was at fault , or carrier bearing or too tight chain adjustment, or chain was skewed // instead of straight || etc ) - We supplied a world class AFAM gold chain made in EU, so 600 miles is worrying for us and not good. Fortunately, the sprockets are fast and appear intact, we will await their reply for us to investigate the "chain" premature wear.

After installing this kit, my 300 can really cruise through every gear without screaming through the ram's. This bike is immensely more enjoyable to ride now and I often leave my iron 883 at home to take the aquila out for a ride. If you only do one thing to your Aquila 300, install this kit. I promise you won't regret it. Great parts, great service. E.