The former Celtic player and Aston Villa captain was diagnosed with acute leukaemia in March.
Villa club masseurs Alex Butler and Andy Smith aim to raise £250,000 by cycling between the stadia of Celtic and Villa Park in Birmingham.
Celtic manager Neil Lennon presented the men with a £5,000 cheque from the Celtic Charity Fund and cycled out of the Glasgow stadium with them as they began the 80-mile first leg of their trip to Newton Saint Boswells in the Borders.
The pair are raising money for the charity Leukaemia & Lymphoma Research.
Former cricketer Sir Ian Botham has done 14 sponsored walks for the charity over 27 years, the most recent of which started in Glasgow in April.
The Celtic manager joined Sir Ian then on part of the walk and said he supports all efforts to raise awareness of illnesses such as leukaemia.
Lennon said: "I spoke to Stan about six weeks ago. He's in remission now but he's going to go through another heavy course of chemotherapy over the next few weeks. When it first came about it was a huge shock to everyone, particularly those who are close to him. But he's such a larger-than-life character and he's battling through it with great honour and dignity.
"You can see what it means to those who are close to him, I mean these guys work with him at Aston Villa and they've decided to put their bodies on the line really to raise awareness of the illness. And it just shows you what Stiliyan means to so many people, not just at Villa Park but at Celtic where he was a great player too."
Around 30,000 people are diagnosed with blood cancer such as leukaemia, lymphoma or myeloma in the UK every year.
The Pedal for Petrov will take the masseurs to various football stadiums in England including Newcastle United's Sports Direct Arena and Everton FC's Goodison Park in Liverpool.
The masseurs said they are doing the cycle to entertain Petrov during his treatment.
"We've all been at the club for around the same period of time and we get on really well, and he's always looked after us. When we needed him he's been there so when he needed us we wanted to show him that we love him," Mr Butler said.
"He's a friend of ours and to do something like this just to keep his mind going while his treatment is going on is important to us."
Mr Smith said: "When something like this happens the football community all come together, and we've had great support from clubs, fans and just people in general because it's for a good cause. We want to thank everyone who has supported us and got involved.
"Hopefully we can make Stan laugh when he sees us struggling on the bikes over the week and it will be worth the effort."