Name: Carburettor Float Valve Screw x2 [Carb Bolt] - Hyosung GT125 GTR GV250 GT250R GV125
SKU: 13377HG5100
Availability: InStock

Carburettor Float Valve Screw x2 [Carb Bolt] – Hyosung GT125 GTR GV250 GT250R GV125

Estimated delivery dates: Apr 21, 2026 - Apr 22, 2026

£4.99

🛠️ -TYPE FLOAT VALVE SCREWS (x2) | REBUILD ESSENTIALS

Ditch the rounded, rusty fasteners. These screws secure the float valve seat system in your Mikuni carburettors. Essential for any rebuild or service, these high-quality replacements ensure your float system stays seated perfectly for smooth fueling.

✅ Genuine Fit: 1-to-1 match for the original Mikuni hardware (Part #13377HG5100).
🛠️ Maintenance Must-Have: Replace worn fasteners to avoid future stripping issues.
⚙️ Symmetrical Set: Supplied as a pack of 2 (One for Front Carb, one for Rear).
📦 Diagram Ref #72: See the technical diagram above for exact positioning.

⚠️ PRO TIP: These screws are delicate! Always use a JIS (Japanese Industrial Standard) screwdriver. Standard Phillips drivers are the #1 cause of these screws rounding off.

In stock

Description

When performing a carburettor rebuild on your Hyosung 125 or 250 v-twin, the small details make the difference between a successful tune and a frustrating leak. The float valve screw holds the entire seat system in place; if this screw is loose, rounded, or corroded, your fuel levels will never be stable. Our replacement screws are a 1-to-1 match for the original hardware, providing a secure, reliable fix for your Mikuni carbs.

💎 Performance with the Reliability!

Don’t settle for “near enough” hardware from a local DIY shop. These screws are designed specifically for the tolerances of the Mikuni carb body, ensuring they won’t vibrate loose or damage the delicate internal threads.

Genuine Type Exact factory specifications.	Twin Pack Covers both Front and Rear carbs.
Zinc Plated Resists corrosion in the fuel bowl.	Secure Fit Prevents float seat movement.

📜 Confirmed Fitment Guide (Carburettor Only)

This kit includes 2x screws, enough for a full service on the following models:

✅ GT125 / GT125R / GT125RC: All Carburettor Models
✅ GV125 Aquila / Mirage: All Models up to 2017
✅ GT250 / GT250R / GV250: All Carburettor Models

Reference OEM Part Number: 13377HG5100 (Item #72 in diagram)

💡 DOING A FULL REBUILD?
If your screws are shot, your gaskets probably are too. Check out our [Full Carb Rebuild Kits] to get your v-twin running factory-fresh. View Rebuild Kits here.

🔧 Installation Tips

JIS Tooling: We cannot stress this enough—use a JIS screwdriver. A standard Phillips bit will “cam out” and round the head of these small screws.
Clean Threads: Use a tiny amount of carb cleaner on a cotton bud to clean the threads in the carb body before fitting the new screws.
Don’t Overtighten: Brass and alloy carb bodies are soft. Tighten until snug, but do not force them, or you risk stripping the carb body itself.

📧 FITMENT QUESTIONS? Email us with your carb photos. For help with float heights and jetting, join the experts on the HyoRiders Forums.