Heat, doping and Armstrong cause Tour trouble

Harsher weather, rumors of drugs and the presence of a former champion invariably conspire against the tournament

FRANCE: While the battle for the yellow jersey should be dominating thoughts ahead of Thursday's final Pyrenean stage, it has been doping, the heat and even Lance Armstrong hogging attention at the Tour de France

After two baking hot days in the mountains in which several riders -- including Alberto Contador and Vincenzo Nibali -- complained of being unable to breath, Thursday's 195km stage 12 from Lannemezan to Plateau de Beille promises to be even hotter, and harder.

The peloton has been feeling the strain, losing already 21 riders and with more than half of the remainder already more than an hour behind Froome.

The 30-year-old Briton has not been having an easy time of things, off-course at any rate -- his performances on the bike so far have been astonishing.

Following his stage 10 victory at La Pierre-Saint Martin on Tuesday, Froome had to bat away numerous questions about doping.

The Team Sky leader has remained calm in the face of tense questioning but did demand more "respect" claiming people should show some "proof before... making accusations".

Inevitably, though, another dominant performance on Thursday's terrifically tough stage with four categorised climbs -- a second, two firsts and an hors category to finish with -- will obviously not silence the critics.

While much of the press, and certainly social media, are fuelling the speculation, Froome's rivals at least seem to be on his side.

"Froome is better than the others," admitted Contador, 32, the two-time former winner currently sitting sixth, more than four minutes back from the Englishman.

Third-placed Nairo Quintana, just over three minutes back, is also merely concentrating on beating the 2013 champion, to whom he finished second then.

"Froome has an advantage but I feel good and as long as there are still mountains to come I won't be throwing in the towel," said the 25-year-old Colombian.

Yet the sceptics are many, such as Belgian journalist Karl Vannieuwkerke who likened Froome's style to that of disgraced drug-cheat Armstrong.

"I can't help it but every pedal-stroke by Froome makes me thing of Armstrong's pedal rate," he wrote on Twitter.

Cracks in the Sky armour started to show as he was subsequently blocked from Froome's page, with Vannieuwkerke replying that Armstrong had done likewise.

Sky back-tracked quickly and apologised before unblocking Vannieuwkerke's access to Froome's Twitter account.

The Tour, and Froome, cannot escape from Armstrong's dark shadow, though.

The American is taking part in a charity ride to raise money for leukaemia sufferers.

The ride, organised by former England international footballer Geoff Thomas's charitable foundation, covers each Tour stage a day before it happens.

Armstrong was due to ride the 13th and 14th stages on Thursday and Friday, but Froome, who many believe is paying for the Texan's past crimes, dismissed it as a sideshow.

"I wish Geoff Thomas and the guys all the best in raising as much money as they can," said Froome.

"(But Armstrong) is not on the line with us here, we're not going to see him, it's a non-event for us."