Fist-shaking cyclists who aggressively shout "open your eyes" to apparently bike-blind drivers are sharing in a problem that also worries motorists.

Groups representing cyclists and drivers agree in their condemnation of road rage, and both have also identified drivers "not seeing" cyclists as a key issue.

The dangerous phenomenon has even earned its own acronym in the biking community: "SMIDSU" - "Sorry mate, I didn't see you", according to Patrick Morgan, of the Cycling Advocates' Network.

"Sometimes the brain doesn't process what it's not expecting to see."


Transport researcher and bike rider Hamish Mackie referred to it as "inattention blindness".

"We [as drivers] see what we want to see. As motorists, we are pre-programmed to see other cars and trucks and things that have that shape, especially when we are at intersections. We're scanning left and right looking for a gap. There's quite a bit going on.

"In that state you are under quite a bit of cognitive load."

He and Mr Morgan put this problem among the top things that annoy - and frighten - cyclists regarding drivers.

Mr Morgan ranked it second behind vehicles that passed too close to bikes, which he rated as "really scary. It's dangerous."

In third place he put excess speed.

"Everything is a lot easier at a safe speed. At 30km/h you are much more likely to see someone and be able to take action.

"We think 50km/h in towns is the wrong speed. In residential and shopping streets we should be looking at 30km/h.


"Safer speeds reduce the severity of crashes and the likelihood of crashes."

Interactive graphic: NZ cycling crashes 2008-2012

Automobile Association communications adviser Dylan Thomsen said the three main things drivers would like cyclists to do to be safer on the road were:

Making themselves as easily seen as possible, with lights and high-visibility clothing.

Obeying all the road rules.

At intersections, or when turning, making eye contact with the driver, before turning. This was the best way to ensure the motorist had seen you.

Read more stories in our Cycle Safe series here.