Alpkit have added a range of waterproofs to their direct-to-consumer website. All are good value ..... Gravitas jacket is their super lightweight option though. It is not a bike-specific jacket, but ticks the boxes that I’m looking for. It comes with a fully featured hood, which will fit over a climbing (or riding) helmet, three layer breathable waterproof fabric, a chest pocket, a little mesh stuff sack… and little else