Royal Enfield 144068 – Cylinder Barrel & Piston Kit (3-Ring) – 350cc Cast-Iron Bullet (Std / Deluxe / Electra 4S/5S / Old Models)

Royal Enfield part 144068 is the genuine Cylinder Barrel & Piston Kit (3-ring type) for 350cc cast-iron (CI) Bullet engines. Classic parts catalogues list it as “CYL. & PISTON ASSY 350CC”, while multiple specialist dealers describe it as the OEM cylinder barrel and piston kit 144068 for Bullet Standard 350 and other 350cc iron-barrel models.

This kit replaces the complete cylinder barrel and piston assembly on older 350cc Bullets where the cast-iron block is worn, scored or low on compression. Instead of oversize rebore guesswork and mismatch pistons, 144068 gives you a factory-matched barrel + piston set designed to restore correct clearances, ring sealing and compression on CI engines. Classic suppliers confirm it as suitable for “all 350 Bullets 1955 onwards” and “350cc Royal Enfield motorcycles only,” covering the Indian-built Standard / Deluxe / Electra 4S/5S / Campus / Machismo 350 range, but not 500cc, AVL or UCE engines.

Ideal for full engine rebuilds, restorations and export builds, this kit arrives in genuine Royal Enfield–branded or OEM-equivalent packing (depending on latest supply), ready to bolt on after you check piston-to-head squish and ring gaps as per workshop manual.

🔎 Important: This is for 350cc cast-iron Bullets only. It does not fit 350 UCE, J-Series, AVL (Lean Burn) or Himalayan / 650 Twins.

Key Features

• Genuine-spec Royal Enfield 144068 Cylinder Barrel & Piston Kit – 350cc CI engine.

• Includes complete cylinder barrel + piston + 3 piston rings (3-ring type kit) – ready for assembly.

• Designed for cast-iron 350 Bullet engines – correct bore, stroke and compression for original performance.

• Genuine or factory-equivalent casting with proper cooling fin layout and stud spacing for classic crankcases.

• Eliminates low-compression, oil burning and blow-by issues caused by worn barrels and pistons.

• Suitable for restoration, export builds and long-term touring on classic Bullets.

• Verified by multiple vintage-Enfield specialists as replacement for OEM 144068.

• Packaged and shipped to protect the bore surface and piston crown from damage in transit.

Compatibility Table

Engine type: 350cc Cast-Iron (CI) long-stroke Bullet engine (Indian Enfield / Royal Enfield, pre-AVL, pre-UCE).

*Years approximate; CI production overlapped across markets. Always confirm via engine number and old barrel casting before ordering.

PLEASE CHECK PART NUMBER BEFORE PURCHASE 

Variants

• This listing:

  • Part Number: 144068

  • Description: Cylinder Barrel & Piston Kit (3-Ring), 350cc Cast-Iron Bullet

  • Configuration: 1 × barrel + 1 × piston + ring set (standard CI 350 size)

If you need oversize pistons or 500cc kits, they use different part numbers – not covered by 144068.

FAQs

Q1. Which engines does 144068 actually fit?
A: 144068 is for 350cc cast-iron (CI) Bullet engines only – Standard, Deluxe, early Electra 4S/5S and similar 350 CI variants. Classic catalogues describe it as “CYL. & PISTON ASSY 350CC,” and multiple suppliers market it as a 350cc Bullet kit only.

Q2. Does this fit Bullet 350 UCE or new Bullet 350 J-Series?
A: No. UCE and J-Series engines use completely different alloy cylinders and part numbers. 144068 is for old cast-iron engines with separate iron barrel and crankcase, not for UCE or J platform bikes.

Q3. Some sites show Bullet 500 / Lightning 500 with 144068 – is that correct?
A: We treat that as incorrect / generic tagging. Factory lists and specialist shops define 144068 as a 350cc kit; 500/535 engines use different bore and dedicated part numbers. To avoid returns and engine damage, we do not recommend 144068 for any 500/535 model.

Q4. Is this kit standard size or oversize?
A: Classic suppliers list it as a “STD complete” cylinder + piston assembly for 350 Bullets. Any rebore/oversize work must be done by a machine shop using the correct oversize piston, which is a different part.

Q5. What else should I replace during installation?
A: At minimum: head gasket, base gasket, circlips, small-end bush check, and a full decarbon + valve-lap. Many builders also fit new cam followers, timing side bearings and oil pump check if the engine is already open.