Castelli’s T1 Stealth triathlon-specific aero bike jersey tested, rated and reviewed

Castelli Stealth Jersey ReviewCastelli T1: Stealth


While it’s normal practice for drag-saving swimskins to be used during a triathlon’s first leg, Castelli are the first to bring a cycling-only triathlon-specific aero top to the market.

Castelli say the top, which was developed using CFD, can save three minutes over a five-hour Ironman bike leg compared to their Free Tri suit, which was worn by both victors in Kona last year.

The body-hugging top was a bit tricky to pull on over damp skin but dried quickly on the bike and was comfy when worn over another form-fitting layer. Silicone grippers help the top from riding up.

The front of the suit uses the same Velocity fabric found in Castelli’s TT speed suits, while the back is made up of highly breathable mesh and also features a pair of fairly generous side entry pockets.

You can let a little – or a lot of – extra air in thanks to the full length zip. As well as the aero advantage, it’s also fantastic for protecting shoulders from the sun too.