Replacing worn parts before they fail is all part and parcel of maintaining any machine. We recommend that as well as you checking your bike regularly, that it is checked by a trained bike mechanic as part of an annual bike service, and more often if you use the bike regularly.
We subject all of our frame parts to stringent testing in-house, and our bikes have to be independently assessed against the relevant ISO and EN standards for a City Bike or in case of the Electric bike against the more stringent Electric Bike testing.
While the chain and sprockets will gradually perform less well as they wear out and give clear indications that they need replacing, parts like the crank arms and handlebars don’t give such clear signals that they are nearing the end of their useful life.
As with all bicycles, aluminium parts such as crank arms and handlebars are subject to material fatigue. Aluminium is a great choice for these components for a number of reasons: it’s lightweight, stiff, and cost-effective. However, it is also less resilient than steel, and for this reason, we recommend aluminium parts, particularly safety-critical components, are replaced within 5000 miles - sooner for vigorous riders, and especially after an accident or significant impact. To give an indication of time; assuming you commute 10 miles per day in total, and use your bike 3 times a week for 48 weeks of the year; your aluminium parts will need replacing approximately every 3.5 years.
Any damaged components because should be replaced before the bike is ridden, any deep scratches or gouges in the aluminium parts can severely weaken the component and cause premature failure of the part. Aluminium parts include but are not limited to, the crankset, the pedals, hinge clamp plates and the handlebars.
Full warranty terms can be found here.