Rye and the surrounding areas are great for road cycling on the flat roads, and is a good way of taking in the picturesque Rye Bay countryside.
Here is a link to the National Cycle Network route 2 showing several local routes http://www.eastsussex.gov.uk/leisureandtourism/countryside/cycling/guidesandmaps/ncn/ncr2.htm
Bedgebury (16.6m) is great for mountain bike trails in the forest for all levels: https://bedgeburypinetum.org.uk/home/activities/cycling/
Bewl Water – cycle path around Bewl water lake, with a nice cafe after
Electric Bike Hire – Rye Bay E-bikes, maybe cycle to Winchelsea
Rye Hire – Bike hire: https://www.ryehire.co.uk