Incumbent Pat McQuaid, who hopes to secure a third term, and his challenger Brian Cookson have been trading bitter blows for months, accusing each other of bending the rules as cycling still reels from the Lance Armstrong doping scandal.
Irishman McQuaid, who was first elected in 2005, is seeking another four-year term to, he says, get rid of the doping culture in the sport.
Cookson, the British Cycling president backed by Russian oligarch and Katusha team owner Igor Makarov, has promised to change the way the sport is governed, with notably the creation of an independent anti-doping authority.
"The riders are the last ones to be asked. We're just pawns in their games," said Briton Bradley Wiggins when asked about Friday's election.
The 2012 Tour de France champion, however, believes Cookson "is already in".
The election will be decided in a vote by 42 delegates at the UCI Congress at Florence's Palazzo Vecchio.
Cookson believes he will have all 14 European votes after the delegates were instructed to back the Briton following a vote at the European Cycling Union (UEC) earlier this month. The UEC, however, has no control over the delegates' votes.
The presidents of the federations of Canada and the United States have expressed their support for Cookson, who has also received the backing of the Oceania confederation and its three votes.
The American confederation, which has given no instruction to its delegates, has nine votes.
McQuaid is relying on Asia (nine votes) and Africa (seven votes).
The Irishman, however, is not even sure he will be able to stand for re-election after failing to secure nominations from his home federations - Ireland and Switzerland, where he resides.
Thailand and Morocco have nominated McQuaid, but the UCI's constitution only allows for presidential candidates that have been nominated by their home federation.
On Friday morning, the UCI Congress will vote for or against amendments to the constitution, which would allow McQuaid to stand.
"Even if Mr McQuaid falls foul of the nomination process, even if congress say that he doesn't have a valid nomination, I will still ask for a positive vote in favour of me by the congress," Cookson said.
"I will not take on the job by default. I don't want a coronation, I want a proper election and I want to take on the role of UCI president with the full support of the congress.
"I'm not a magician myself, I'm trying to stick to the rules," Cookson added. "I'm trying to run a campaign with integrity and honesty. I think the UCI has seen too much of these shenanigans - I hope that's a word that translates easily - these kind of machinations in the future."
That assertion was contested on Thursday when the president of the St Lucia federation said he was offered an incentive by one of Cookson's PR people should he vote against McQuaid.
In a letter to all cycling federations, Cyril Mangal, who supports McQuaid, wrote: "St. Lucia is very concerned that when we were contacted by someone supporting Cookson, the person indicated 'I would like you to be on the right side after the election, so you are on the priority list of the federations which would be helped.'
"We sincerely hope that this would not be the way Mr Cookson would operate should he win the presidency of the UCI."
Cookson has denied the allegation.
- Politics & Government
- Brian Cookson
- Pat McQuaid