Stellenbosch University students Ronel and Jago Liss are consulting a lawyer after Cape Argus/Pick 'n Pay Cycle Tour organisers accused them of failing to follow the full route.
Ronel Liss claimed to have won the women's race.
The couple's lawyer, Peter Hill, said on Wednesday that his clients maintained that they had taken part in the tour in a "regular and proper" manner .
"We are considering all our options, including suing the tour organisers," Hill said.
A friend of Ronel Liss, who was disqualified after claiming victory, said she was a victim of the failure of the race measuring equipment.
Neither Liss nor her husband, who apparently came first in the A group, were recorded on the transponder timing mat on Ou Kaapseweg, and Ronel Liss was not seen in any video footage of the race.
She told race organisers that she had taken her transponder strap off early in the race because it was irritating her, putting it back on shortly before the finish.
On Wednesday her friend, Annette Pluddemann, said she had been denied the title because of a technical error.
"The race organisers were let down by their failing transponder equipment and Ronel is paying for their problem by having her character assassinated, being accused as a cheat," Pluddemann said.
In fact no one has accused the Lisses of cheating. But the tour technical committee, which looked into the circumstances of the couple's rides found it "inconceivable" and "too much of a coincidence" that neither was seen by other cyclists, nor captured on video during most of the route, nor recorded riding over the Ou Kaapseweg transponder timing mat.
After studying extensive video footage from static cameras along the route and tapes from mobile camera crews who followed only the leading bunches, tour organisers decided that Ronel Liss could not have completed the route.
Her husband's win in the A group was now also being investigated, said tour co-chairman David Bellairs.
Bellairs would not label the Liss couple cheats, nor would he speculate about what may have happened.
"Jago's win is still being investigated, but we are satisfied that Ronel could not have completed the full route. As far as we are concerned, her matter is closed," he said.
Her husband had not explained why the timing mat on Ou Kaapseweg had failed to record his transponder.
Describing her race, Ronel had been vague, telling the committee that she had broken away from the leading women riders "somewhere between Muizenberg and Scarborough" (a 30km section of the tour).
But the eventual winner of the women's section, Anriette Schoeman, said she had been watching her rivals carefully and had broken away from her strongest opponents, Ronelle van Wyk, Adelle Janse van Vuuren and Mari Rogers, at the approach to Ou Kaapseweg.
Three years ago, Ronel Liss completed the cycle tour in a time of more than three-and-a-half hours. This year, after a two-year absence, she apopeared to have beaten Anriette Schoeman's winning time of 2hr 57min 34 sec by 15 seconds.
Her spectacularly improved times in this year's Pedal Power Association races led to her being reseeded for the Cycle Tour, enabling her to start in the C-group.
Liss, a masters student at the University of Stellenbosch, refused to speak to the media and directed all enquiries to Hill.
The couple are both doing research for masters degrees in microbiology.
Staff at the microbiology department said they were hard-working students and described Ronel Liss as someone who "keeps a low profile" and Jago as "reserved".