Why is Shimano out of stock?
Decathlon's cycling market leader Peter Lazarus foresees these shortages of Shimano components continuing through 2021 simply because it takes time to expand a company such as Shimano's production capacity. “Manufacturing plants only have a certain degree of elasticity in their production lines.
Which Shimano groupset is best?
Shimano 105 is considered Shimano's first performance groupset, and for many people it is the best option in combining performance, value and longevity. Ultegra is next and is very similar to Dura-Ace in terms of performance, though Dura-Ace is lighter. You'll find Ultegra on bikes from around £2500.