If you’re bringing a bike, verify cycle policies on trains; some lines restrict non-folding bikes

https://holdencrae327.almoheet-travel.com/heathrow-express-vs-elizabeth-line-fastest-way-to-heathrow-from-central-london-2

If you’re bringing a bike, verify cycle policies on trains; some lines restrict non-folding bikes, so consider airport buses with luggage racks instead.