Billy explained what the ride is all about:
"My Mum is cycling from my home village, Wisborough Green, in West Sussex to Kingsholm, arriving on the day of the Saracens game.
"She's doing it for Smile for Wessex which is a charity she's supporting after she suffered a brain tumour back in 2006. If it wasn't for them and the hard work of the Southampton hospital, she probably wouldn't be with us today.
"Me and my family are very grateful for that, and she just wants to give something back to try and help people who find themselves in a similar position.
"She's not 100% in the clear but she's doing well, and she's very grateful for everything that's been done for her. She's happy to be alive and have her family around her, and now wants to help raise some funds to give something back."
It's a tough challenge, but Billy knows that his Mum has got what it takes and feels he has inherited certain personality traits from her.
"She's a bit like me, she's very ambitious. I've got three brothers and she wants to get us all involved in some way and make it a family affair.
"I think it's about 150 miles in total and she'll be the first to admit that she's not the fittest lady after all that has happened. It's a big challenge and she's planning to do 30 miles per day. She's actually really looking forward to it.
"I've given her some tips on nutrition and recovery, but she doesn't seem too keen on the ice baths! But she's a hard worker and she'll dig in for sure.
"From a personal point of view, I wouldn't be here today if it wasn't for my mum. She's the driving force behind my rugby career, she's given me huge confidence and ambition in my whole career and life.
"It's huge for me to get behind her because she's done so much for me."
You can sponsor Beverley by visiting the uk.virginmoneygiving.com website and searching for Bev's Big Bike Ride.