Time Away

We will be closing for Two week in Mid May Our last trading day will be Friday 8th May 2026.
Any orders placed after this date will be processed when we reopen on
Monday, 25
th May.


Stainless Steel Domed-Head Bolt – Replacement Bolt for BSA / Triumph / Sunbeam 28-2338

Upgrade your classic British motorcycle with this premium CNC-machined stainless steel replacement bolt. Made in small batches in Cornwall, England, it is a perfect cosmetic and functional upgrade over the original mild-steel item.


Key Features:

Part Number: 28-2338

Material: Stainless steel

Length: 11/16" under head (17.46mm)

Thread: 5/16" x 26 TPI (BSCY / CEI)

Spanner Size: 1/2" - 12.7mm (Originally 15/32" AF 11.9mm)

Unlike most alternatives on the market, our bolt features a beautifully domed head. When polished, it adds an elegant touch to your motorcycle’s aesthetics. (See photos for details.)


Versatile Application: This bolt is designed to fit various parts across multiple BSA, Triumph and Sunbeam models, including:

  • Mudguard Stay Bolt
  • Mudguard bolt
  • Under shield Fixing Bolt
  • Oil tank clip Fixing Bolt

Produced in Cornwall, England by CPC Engineering using precise CNC manufacturing techniques, ensuring consistent quality and performance.


Pricing: Price is per bolt.

28-2338 - 5/16" BSCY Bolt - 11/16" Under-Head

  • £6.00

  • Ex Tax: £5.00

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