Carb Diaphragm [Throttle Slide Piston] – Hyosung GT125R GV250 GT250R GV125
Stop the bogging and bring back the crisp throttle response. These precision-moulded rubbers restore the perfect vacuum seal required for smooth lifting of the slides, making a fresh Hyosung carb diaphragm replacement the single best way to clear up mid-range flat spots on local roads.
- Action // Eliminates sudden engine hesitation, hunting, and inconsistent idle tracking.
- Quality // High-grade composite rubber slide assembly built to match factory specifications exactly.
- Fitment // Drop-in sizing verified to overhaul standard carbs on 125cc and 250cc twins.
- In Stock // Get back on the road sooner with fresh replacement pistons packed and ready for your project.
1️⃣2️⃣5️⃣ = 2125cc rubber slide kits contain TWO (2x) pieces. It is needed for both cylinders.
❌💉 Needles are not included.
2️⃣5️⃣0️⃣ = 250cc rubber slid kits contain ONE (1x) piece. Change checkout quantity to 2x if you are refreshing both 250cc bodies together.
Description
After years of continuous exposure to modern ethanol-blended fuels and intense engine heat soak under the tank, the original rubber components inside your fuel mixing blocks become stiff, brittle, or develop pin-sized tears. This slow maintenance reality means your internal slider blocks will not pull up evenly under vacuum pressure, causing your engine to feel completely lazy or bog down heavily whenever you click into gear. Swapping out your perished rubber for this fresh Hyosung carb diaphragm assembly is the most cost-effective way to restore that original snappy throttle response. It patches up critical vacuum leaks and completely cures mid-range flat spots on local roads.
A healthy vacuum membrane ensures that your fueling mist remains completely consistent and balanced across your entire rev limits. By managing the slide lift with absolute precision, you stop over-rich fuel dumping, clear away persistent coughing, and get much better mileage out of your fuel tank during long weekend projects.
💎 INDUCTION REBUILD HYOSUNG CARB DIAPHRAGM SPECIFICATIONS
| Fixes Engine SurgingMaintains a constant vacuum pull to keep your engine speed completely stable while cruising. | Cures Heavy BoggingDelivers immediate slide lift the exact millisecond you pin your handlebar twist grip open. |
| True Factory BlueprintTurned and molded accurately to replace old parts matching factory codes: 13338HG5100. | Improves Tank MileageEnsures correct fuel metering to stop lazy acceleration patterns and heavy exhaust soot. |
📜 Confirmed Fitment Guide
Carburetted V-Twin Engine Group: Housing sizes and slide diameters are verified to drop straight into the original fuel bodies listed below. See the diagram picture for top cap seating tabs.
- Hyosung GT125 / GT125R Sport: Fits all traditional twin-carb sport models across all years.
- Hyosung GT250 / GT250R Sport: Fits classic twin-carb setups up to 2007.
- Hyosung GV125 / GV250 Aquila Cruiser: Fits carburetted cruiser layouts (GV125 versions up to 2017).
Long tapered fuel needles are NOT supplied inside this pack. Remember to carefully swap your old pins over or check out our shop selection for upgraded adjustable jet needles.
🔧 Install Tips
- Cleanliness is Always Key: Use a generous blast of spray cleaner to thoroughly clear away any sticky yellow fuel varnish, dry grit, or carbon lines from your alloy carb towers and slider tracks before you attempt to fit the new flexible rubber.
- Seat the Outer Lip Perfectly: Take your time when laying the circular outer edge of the diaphragm into the alloy casing groove. It must sit completely flush and flat all the way around before you tighten the top cap bolts, or you will pinch the rubber and cause major vacuum pressure leaks.
- Check Your Slide Springs: While you have your top metal lids unbolted and open on the workbench, inspect your long slide return springs closely for any brown rust spots or distortion that could mess with your slide drop times.
Additional information
| Weight | 0.9 kg |
|---|---|
| Dimensions | 20 × 20 × 20 cm |
1 review for Carb Diaphragm [Throttle Slide Piston] – Hyosung GT125R GV250 GT250R GV125
You must be logged in to post a review.
GARAGE PICKS // ADD TO BUILD
-
Stainless Steel Float Bowl Carb Bolts Kit – Hyosung GV & GT 125/250 Carburettor Models
£5.99 -
Intake Pipe O-RING (Inlet Boot Seals) x2 – GV125 GT125 RX125 GV250 GT250 Hyosung
Price range: £7.99 through £9.99 -
Stainless Steel Carb Inlet Manifold Intake Clamp x2 – Hyosung GV250 GT125R GV125 GT250
£7.99 -
Carburettor Carb Pilot Jets x2 – Hyosung GV125 GT125 R RC GV250 GT250
Price range: £14.99 through £16.99
EXPLORE // RELATED PRODUCTS
-
NGK LASER Iridium Spark Plugs x2 – Hyosung GT/GV 125 250 650 Models
£29.99 -
Braided Air Vacuum Intake Line Hose Kit – Hyosung GV GT 125 & 250 [Carby Models]
£7.99 -
Complete Stainless Steel Engine Bolt Kit – Hyosung GT GT125R GV125 GT250R GV250
Price range: £18.00 through £21.00 -
SwingArm Spool Kit {Race Stand Bobbins Sliders} – Hyosung GT125 GT250 GT125R GT250R
£34.99
Independent Shop supplying ride enhancements and quality spares with fast dispatch. Need assistance? Access our workshop guides, manuals, tutorials or drop by the forums for troubleshooting help.
Ryan –
If you’re looking to improve your 6-7k rpm I would highly recommend this along with the needle that can also be found on this site. I had boggy type issues and after installing this and the needle it’s gone completely, very easy to install 10/10, great help from Marcel too answering all my questions when needed, top guy!