Ultimately, a lot of this comes down to how honest you want to be with your tax affairs. I've seen sole traders buy bikes, parts, clothing, accessories etc on the business then write it off against profits and have never been challenged by the taxman. Equally I've seen those that only claim the mileage.
I think, strictly speaking, you can't deduct a bike against profits as a sole trader unless that bike is equipement for your business. But mileage, cycle to work, etc should all be taken advantage of in my opinion, as it's cash you're entitled to.
Ultimately, a lot of this comes down to how honest you want to be with your tax affairs. I've seen sole traders buy bikes, parts, clothing, accessories etc on the business then write it off against profits and have never been challenged by the taxman. Equally I've seen those that only claim the mileage.
I think, strictly speaking, you can't deduct a bike against profits as a sole trader unless that bike is equipement for your business. But mileage, cycle to work, etc should all be taken advantage of in my opinion, as it's cash you're entitled to.