Hex Flange Collar Bolt M5x0.8 for Royal Enfield Meteor 350 (Fuel Tank Hardware) | 1100403/B | Genuine OEM

The Royal Enfield 1100403/B Hex Flange Collar Bolt (M5 × 0.8) is a genuine OEM fastener used in Royal Enfield assemblies where an M5 bolt with an integrated flange/collar is required for correct clamp load and vibration resistance. It’s most commonly referenced in Fuel Tank parts catalogues for the Meteor 350 (Euro 5 / UK spec)—ideal when you’re replacing missing/rounded bolts, rebuilding the tank mounting hardware, or doing a clean “factory-correct” restoration instead of using generic hardware-store screws.

Unlike aftermarket bolts that may have the wrong head profile or collar seat, this OEM bolt matches the original fitment spec so panels/brackets sit correctly and you avoid uneven stress on mounts. It is typically shown as a multi-quantity requirement in fuel tank exploded views (often qty 8 for that sub-assembly), so always count how many pieces you need before ordering.

If your mechanic is working on the fuel tank, evap routing, or bracket alignment, using OEM hardware significantly reduces rework, rattles, and repeat loosening.

Key Features

• Genuine Royal Enfield part (OEM hardware)

• Part Number: 1100403/B

• Description: HEX FLANGE COLLAR BOLT (M5 × 0.8)

• Correct flange/collar head profile for factory-style clamping

• Helps prevent loosening compared to incorrect universal bolts (when torqued properly)

• Commonly referenced in Meteor 350 fuel tank hardware listings 

• Ideal for replacements during tank removal, repaint, or bracket service

• Sold as single bolt (order required quantity as per your assembly) 

Compatibility Table

❓Not confirmed (excluded to reduce returns)

Classic 350 Reborn / Hunter 350 / Bullet 350 and other models may share similar M5 hardware, but part-to-model confirmation wasn’t available from open microfiche pages in this run, so they’re intentionally not listed.

Variants

• Single unit (one bolt)

• No LH/RH, no color variants specified for this part number in dealer listings. 

FAQs 

1) What exactly is 1100403/B?
It’s an OEM Hex Flange Collar Bolt (M5 × 0.8) used by Royal Enfield. 

2) Is this sold as a set or single piece?
This listing is for 1 bolt. Many assemblies require multiple bolts; fuel tank fiches often show multiple quantity (commonly 8)—count yours before ordering. 

3) Where is it used on Meteor 350?
It appears in Meteor 350 fuel tank parts/hardware catalogues. 

4) Can I use a normal M5 bolt instead?
A generic M5 may fit the threads, but flange/collar profile and seating can differ—OEM is recommended for correct clamping and alignment.

5) How do I avoid ordering the wrong bolt?
Match by part number 1100403/B or compare your removed bolt head style + thread spec (M5×0.8).