According to the latest opinion poll, Boris Johnson has opened up a five-point lead over Ken Livingstone in the race for City Hall.

A YouGov survey of 1,003 Londoners for London Tonight puts Boris on 44 per cent, Ken on 39 per cent and Brian Paddick on 12 per cent.

Compared to a similar poll by the same organisation over Christmas, Boris’s support has not changed, Ken has dropped six points and BP has jumped five, but is still polling well below his party nationally.

Today at his City Hall press conference, Uncle Ken declined to reveal the results from private polling for the Labour party.

This is believed to give him an 11 per cent lead over Boris when respondents are asked who they would chose for Mayor, but reduces to seven points when respondents were asked if they were likely to vote, and then to three per cent when it includes only those sure to vote.

Ken, who seemed relatively unruffled by the YouGov internet survey, said of the Labour poll: “You can tell from my face I wasn’t unhappy with it.”

As for Boris, he has jumped into the lion’s den with his pledge today to allow motorbikes into bus lanes.

This could pit the city’s most famous cyclist against many fellow pedalers, who believe that bus lanes are going to get a whole lot more terrifying if motorbikes and scooters are permitted.

As a city cyclist myself, my initial thought is that Boris has got it badly wrong. I know from experience that being “buzzed” by a lunatic on a scooter or a motorbike is terrifying – and carries the potential for a very nasty collision or fall indeed.

But the findings from a never-ending TfL pilot study of allowing “powered two wheelers” into bus lanes – it’s been carried out for more than three years on the A23 in Brixton and the A41 Finchley Road – says that in fact the move is safer for all concerned, and cuts accidents by almost half.

Uncle Ken fears incurring the wrath of militant cyclists and has declined to back or reject the initiative - instead calling for more analysis.

But let's look at the statistics. According to TfL, 19 cyclists were killed on London’s roads in 2006 and 373 were seriously injured. Among motorbikers etc, the figures were much higher – 43 fatalities and 805 serious injuries. (For reference, 100 pedestrian were killed on roads and 1,203 were seriously injured.)

The Mayor is committed to cutting casualties among all three groups by 2010, but TfL’s own safety advisors warn the desired 40 per cent reduction among motorcyclists and scooter riders is unlikely to materialise.

On this basis, allowing bikers to join cyclists in all bus lanes should be a good thing, and should save lives. But a voice in the back of my head continues to wonder whether this is a good move for those who bravely pedal their way around the city.