Description
520 Upgrade Chain & Sprocket Kit (Conversion)
Hyosung GV125-S EFi (Injected Models from 2019)
🚚 4-6 DAYS UK DELIVERY #WE SHIP WORLDWIDE. EMAIL US. .
After great success with our CARB VERSION of the 520 chain & sprocket kits (see here), we have decided to offer 520 chain kits for the iNJECTED EFi Models of GV125-S Bobber
Hyosung GV125-S EFi Bobber now benefits from a special & complete 428-to-520 conversion chain & sprocket kit!
Or put simply this…
You will have more top end over any stock 428 kit. #guaranteed
You will accelerate better in low gears #guaranteed.
You will cruise in lower gears #guaranteed.
Our 520 kits outlive all stock 428 chains, so it’s great for Distance Touring!
📦 Product Details (Full Bundle Kit):
⚙ Yamaha Front Sprocket AFAM EU | TC | SS | HENDLER UK |
⛓ 520 Jap Chain TKR | RK | TSUBAKi | DID | etc |
⚙ 520 Rear Sprocket Silver or Black [random] see gallery above ^ 📷 |
🔧 Genuine Hyosung Washer | We also supply high quality EU chains from AFAM, DC | Chain Colour will be Black/Silver |
🏁 This 520 Kit Vs Stock 428 Setup
🏁 Accelerate to 70mph faster than stock OEM 428 chain. #Guaranteed. For Hyosung GV125-S EFi using our 520 chain & sprocket kit SEE BELOW FOR GPS VIDEO! |
🛣 Top Speed Potential? (Probably 78-85 max?!) (Indicated on dashboard at max revs) We can even customize the gearing for your order. Just tell us! Stock sprockets on GV125-S EFi usually has a standard low top speed of 65mph ish. Do you want to go faster? |
⚙ Lower Revs in all gears. Want to cruise all day? |
🌄 Tour Ready! Ride long distance with less adjustments |
⚙ Cruise in lower gear Shorter city rides are better too! |
🏍 Exclusive to GV125-S EFi (2019+ onwards) Only on HYORiDERS SHOP 👌 |
🎥 Customer Video Showcase
🎥 GPS ViDEO
Chain Kit is capable of doing 130 KMH+ (80+ mph). Our customer from EU has noted his country’s National Speed Limit was 120 km/h, and he was able to confirm he could keep up with high speed vehicles with a 520 kit now. Also, our 520 kit also helps you keep speed near the hills, notice the “elevation” in the clip below. Some roads are up hill or inclines.
🚚 UK DELIVERY TIME :
This is a special kit that takes 4-6 working days to arrive at your UK Address
✈ International Buyers = Please email us for a quote! We ship worldwide
👍 Hyosung Model |
✔ Fitting Instructions |
📦 Product Colours |
GV125-S EFi only ( 2019 onwards ✔ ) GV125-S Injected Models Only. |
Just swap & go #Literally. or Click Here For Tutorial |
Rear Sprocket is Silver or Black (random) Chain => Black or Silver or Gold (random) |
❌ IT WILL NOT FIT CARBY / CARBURETTED MODELS
( It is strictly for injected versions from 2019+ onwards )
❕❗ FOR CARB VERSIONS => GO TO THIS LINK HERE (TAP HERE⛓)
GV125S ONLY |
From 2019 – Present | 📷 Example below |
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❌ Will NOT fit “GV125-SS EVO”
❕ ❗ EVO (SS) models use different parts!👉 PLEASE EMAIL US IF YOU HAVE A “GV125-SS EVO” MODEL FOR SPECIAL CUSTOM KIT! |
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Need more detailed help? Visit the Forums! or send an email if you prefer to!
Ref OEM # = 27510H41732JS , 27600KG7200 , 64511KG7200
Eddie –
If you are debating whether or not to get the 520 upgrade then the short answer is YES…get it. If you want to know why you should, continue reading……
I was unsure if the expense would be worth the investment, after all the GV125S in it’s self is a decent cruiser and with the stock sprockets I could achieve 67 mph if the weather was on my side. I found it slow getting there all the same and at top end the bike would be hurting…..you could hear that she didn’t like being redlined. I contacted Hyo Riders and Marcel was so helpful in arranging the upgrade I needed. Once fitted I noticed I was up to speed much, much faster than previous and the gearing and revs seem more in tune. I find that 4th can be a cruising gear….enough pull to get you along and when needed take you to 60 mph , I only really use 5th for when I’m on open carriageways. I have achieved a top end speed with this conversion of 75 MPH and considering I am 12 1/2 stone , the bike has panniers and a topbox and I am fully kitted when riding, I think that is impressive from a upgrade. At this stage I’m sure I have covered most of what is needed to know…..and in fairness , the promises made as to what this 520 upgrade would deliver have been spot on. Well done Hyosung Riders 10/10. Again a big thank you to Marcel for all his help in this, you are a star….
Stuart (verified owner) –
Really great. Low end acceleration is much better and gets up to 60 in 4th (used to have to use 5th for this). Got it up to 70mph, although it did take a while (previously only got up to 67pmh), but I ran out of road. Pretty sure it would have been up to 75mph+ on a longer carriageway
Charlie (verified owner) –
So got this set few weeks ago as i wanted a bit longer gears. im using it in city, heavy traffic, daily commuting. Before was changing gears like a lunatic 1st to 4th non stop.. this set sorted my problem a lot to be fair. 20-35(40 with screaming engine) mph in 3rd gear. 2nd gear comfortably around 25.. unfortunately havent tried whats the max speed now as grown up life sucks and havent had time to push the bike yet
G. Limet –
What a great kit this is!!
Delivery to belgium was very quick!
I’m happy with the result.
Don’t have to shift as mutch as with the original chain. Lower revs and more accelaration. And a higher top speed. If you buy this kit you won’t regret it!!
Top notch!
Thanks marcel!!! Greetz from belgium
Koen Schockazer –
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.
C-J –
Great item arrived well packaged and quickly loved the little notes that Marcel put on the items like the torque pressure thankyou so much hopefully it means I will be able to get my bike back on the road after failing it’s mot
Ale (verified owner) –
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