Classic Triumph motorcycles typically use UNF (Unified National Fine) nuts and bolts, which are imperial-sized fasteners. CEI nuts can also be found on many Brit bikes. Here are some key points about nuts for British motorcycles:

Types of Nuts for British Motorcycles

Nyloc Nuts

Nyloc nuts are commonly used on classic Triumphs, particularly for handlebar mounting clamps. These nuts feature a nylon insert at the top to prevent accidental loosening due to vibration1. They are ideal for:

Parts that pivot and cannot be fully locked down
Areas subject to vibration

However, Nyloc nuts are not recommended for use where temperatures exceed 250°F (121°C).

Standard Nuts

Grade 5 UNF nuts are typically used for general applications on classic Triumphs. These provide a good balance of strength and durability for most motorcycle components.