
Aftermarket Honda PCX 125 Cylinder Head Gasket (12251-KWN-900) | 2010-2020
Running a Workshop or Delivery Fleet? Unlock Up to 75% Trade Discount.
Discover the ultimate upgrade for your motorcycle.
Designed with precision engineering, this offers unmatched performance and durability.
Designed to handle intense combustion heat, this Honda aftermarket Cylinder Head Gasket (12251-KWN-900) restores a perfect high-pressure seal for the Honda PCX 125 (2010-2020). Its reinforced construction eliminates compression loss and prevents coolant leaks, ensuring reliable engine performance for your daily commute.
Vetted by our Lead Engineer. Leveraging 30 years of mechanical pedigree, every part is inspected for material density and exact tolerances to ensure a 'Right-First-Time' fit.
Guaranteed fitment for Honda PCX125 or free returns.
Delivery Information
Orders placed before 12:00pm (UK time) are usually dispatched the same working day. Orders placed after this time will be dispatched on the next working day.
In the rare event of a stock shortage, we will notify you promptly and issue a full refund within one working day if the item cannot be supplied.
Once dispatched, tracking information will be provided via email, provided valid contact details are supplied at checkout.
While we aim to meet all estimated delivery times, delays may occasionally occur due to circumstances beyond our control, such as courier issues, weather conditions, or operational disruptions. Should this happen, we will keep you informed.
Delivery Areas
We currently deliver to:
• United Kingdom
• Republic of Ireland
• Isle of Man
• Jersey & Channel Islands
• Most European destinations
If you are unsure whether we deliver to your location, please contact us prior to placing your order.
Verified UK Entity #15361806 operating from our NW10 London Logistics Hub. Skip the wait with express workshop pickup.

Product Compatibility
Compatibility charts are for reference only. Please compare part numbers and manufacturers' details. Contact us before ordering if unsure to avoid delays or refund charges.
Trademark Disclaimer: All trademarks, brand names, and logos remain the property of their respective owners and are used solely for identification and compatibility purposes. We are an independent retailer and are not affiliated with any authorized dealer or distributor.
- 12251-KWN-900
_
- 12251-KWN-901, 12252-KWN-900, 12251-K12-901, 12251-K40-F01, 12252-K40-F00, 12391-KZR-600
- PCX125
- 2010
- 2011
- 2012
- 2013
- 2014
- 2015
- 2016
- 2017
- 2018
- 2019
- 2020
- Honda
- 125
- PCX125
- NEW
Product Overview
This high-quality Head Gasket Cylinder is designed to meet or exceed factory performance standards and is suitable for Honda PCX125 (2010-2020) models.
The head gasket cylinder is a critical sealing component that sits between the cylinder head and the cylinder barrel, maintaining a gas-tight seal to contain combustion pressure while also preventing engine oil and coolant from mixing or leaking externally. When the head gasket fails, the result can be a loss of compression, overheating, white or blue smoke from the exhaust, coolant contamination of the engine oil, or external oil and coolant leaks that gradually worsen under the heat and pressure of normal riding. This quality aftermarket replacement is built to match original specifications, restoring reliable combustion sealing and engine integrity to your PCX125.
- Brand New Aftermarket Head Gasket Cylinder
- Part Number: 12251-KWN-900
- Alternative Part Numbers: 12251-KWN-901, 12252-KWN-900, 12251-K12-901, 12251-K40-F01, 12252-K40-F00, 12391-KZR-600
- Compatible with Honda PCX125 (2010-2020)
- Restores a gas-tight seal between the cylinder head and cylinder barrel
- Prevents combustion gas blow-by, compression loss, and external leaks
- Direct replacement, no modification required
- Ideal for top-end engine rebuild and scheduled cylinder head servicing
- London: Express same-day delivery (2-3 hours)
- Rest of UK: Same-day dispatch on orders before 1 PM (3-4 business days delivery).
- Up to 75% off for B2B Trade Accounts. Independent UK garages, apply now.
• Honda PCX125 owners with a blown, leaking, or failed head gasket
• Replacing the Head Gasket Cylinder during top-end engine rebuild or cylinder head removal
• Mechanics and workshops carrying out Honda PCX125 engine overhaul or cylinder head servicing
• Riders wanting to restore reliable combustion sealing and engine integrity to their 2010-2020 PCX125
• Anyone looking for a quality aftermarket replacement for their Honda PCX125
Complete Part Guide
The cylinder head gasket is the primary high-pressure seal for the 2010-2020 Honda PCX125 engine, responsible for containing combustion gases while keeping oil and coolant separate. A compromised gasket leads to constant overheating, "bubbling" in the expansion tank, and a loss of engine power. This performance-grade Honda aftermarket replacement (12251-KWN-900) provides the exact structural density needed for reliable sealing in North London's demanding delivery environment. In stock at Part Hive's London warehouse, order before 1 PM for same-day UK dispatch.
We frequently find 2010-2020 Honda PCX-125 units with "milky" oil or white exhaust smoke, classic indicators of a 12251-KWN-900 gasket failure. In the heavy traffic of North London, these engines often run hot, causing the head gasket to fatigue over time. This trade-grade Honda aftermarket Head Gasket is a robust solution for engine overhauls, featuring a precision-engineered profile that ensures a rattle-free, pressurized fit, preventing the coolant-to-cylinder leaks and secondary engine seizure often caused by using inferior, low-spec head seals.
You may also like
Get the Right Parts for Your Ride with Part Hive
Finding the perfect part for your motorcycle is easy with Part Hive. Here’s how we make it simple for you:
Wide Selection
From brakes and suspension to mirrors and body fairings, we stock parts for all major motorcycle brands and models.
Easy Fit
Use our filters or search tools to quickly locate parts compatible with your make, model, and year.
Trusted Quality
All our parts are sourced from reliable manufacturers, including high-quality aftermarket options.
Fast Delivery
Order online and get your parts delivered quickly, so you can get back on the road without delay.
Part Hive FAQ
Your Guide to Smooth Rides
How do I add a part to my cart?
Simply select the correct part for your motorcycle (make, model, year), then click the ‘Add to Cart’ button. The item will be added to your cart, and you can continue shopping or proceed to checkout.
Can I change the quantity of a part before checkout?
Yes! After adding a part to your cart, you can adjust the quantity directly in your cart page.
What if I accidentally add the wrong part to my cart?
No problem! You can remove any item from your cart by clicking the ‘Remove’ button next to the quantity. You can then add the correct part if needed.
Can I save items in my cart for later?
Yes. Items in your cart are automatically saved for logged-in customers for a limited time. You can also create a Wishlist or favourites list to save items for future purchases.
