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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