Being a London bicycle commuter *and* a motorcyclist, this is a tough challenge.
Personally I don't have much trouble with the idea of sharing the bicycle lane with considerate scooterists and motorcyclists, and when the traffic is stopped, I'm happy to share as we all move through the gridlock.
However, there is a far cry difference between motorised cycles sharing a bus lane, and motorised cycles using a bicycle-only lane at motorised traffic speeds!
In a bus lane, there is room for a logical order of speeds, slower traffic at the curb, faster traffic towards the middle. In a bicycle lane this is not the case, and frankly, all traffic should travel at bicycle speeds.
I understand that currently, due to this trial, motorised cycles are allowed in the bus lanes, but this doesn't apply to bicycle lanes. This is an important disticntion that our petrol-headed brothers and sisters need to be reminded of. Legally they don't have the right to be there, so they'd better be smart about how they do it. Frankly, I think they *should* be relegated to filtering *between* the cars.
Motorcycles in bus lanes, yes. Motorcycles in bicycle lanes? Only in heavy traffic, and only and bicycle speeds. Simples!