Why?
Roadworks, disruption and upheaval to create a separate lane just for cyclists and they still use the road. It seriously disrupts traffic - eg over Hirzel - but they persist in staying on the street/road.
What is the rationale, if any? Don't they simply endanger themselves and others and cause hold-ups for everyone else?

Lets be honest here - are you complaining because you might be delayed 15 or 20 seconds in your car? Or are you concerned for the safety of your fellow human beings? I do hope it is the latter.....

Cyclists are traffic.

There can be many reasons not to use cycle lanes - if they are full of mud, ice, broken glass or leaves, are potholed, or are too close to the doors of parked cars, it is far safer to ride on the main traffic lanes. If you're turning left, it's much safer to get into the traffic lane earlier so that you are visible.

Generally, cycle lanes are much less maintained than the rest of the road surface, and being up against the kerb means they collect all the rubbish from the road and the pavement. Hitting a glass bottle going at speed in a cycle lane is no fun.

Most cyclists are too busy trimming their sideburns to bother with cycle lanes.

As a cyclist and motorist, when on two wheels, I make every effort to get out of the way of the 'killer car'. But some cyclists, especially those in Lycra, find the cycle paths too pedestrian and venture out into motorised traffic expecting to have total right of way...

I am not sure about the cycle lane in question but often the cycle lanes are full of the slow ridders (Picture mums with those bike trailers and kids) or shared with pedestrains. The cycle path in my areais in front of apartment buildings. In the last week i have almost squished a dog off the leash and today whilst avoiding one child chasing a ball (leaving him lots of space) i almost squished his sister who came out from behind a tall fence. Luckily i avoid going unreasonably fast along this stretch. Those cyclist who want to get somewhere quickly i can see their rational for using the road.

We have a cycle lane and are on a road that is a very popular cycle around the lake. So often, one in the cycle lane, one riding next to them on the road.

Its not that busy with cars so no major hold up but I'm sure taking this attitude elsewhere can cause hold ups.

Im a holdup even in the car going over Hirzel. There are some drivers who know that road well and want to drive very fast. Wifey suffers car sickness especially with those winding bends and i struggle to maintain the speed limit. Especially when she says she's going to be sick

im not normally a turtle but that road i find tough work.

As someone who is often accused of 'Nana-driving', you can rest assured I'm not a speed queen. I just don't understand, even taking into account all the comments about poorly kept cycle lanes (the ones round here are pristine - I use them as a cyclist too) why cyclists don't choose their own safer routes than causing problems on the road and endangering themselves.

I fought for space and risked serious injury cycling round London - to me, Swiss cycle lanes are a paradise.

Coincidentally, I just walked up the shop to buy some milk. A cyclist was sweating up the hill, on the road. Evening traffic, and a queue of cars behind. A clean, shiny cycle path beside him, but he chose to ride on the street. When a break in the traffic allowed the first car to overtake, the driver yelled something like 'Veloweg! Schaffpimmel!'
Which I translated as 'Bike path! Sheep dick!'

So still I wonder ... why? Can it really be because cyclists possess sheep organs?

one thing to remember - cycle lanes generally exist because communities want to encourage the use of bikes as an alternative to autos (or public transport), not for weekend warrior types in lycra tights. men or women who fancy a vicarious Tour de France experience and who choose to pass a pensioner on a 1950's Schwinn in the auto portion of the road are a traffic hazard waiting to happen.

I love bikes and am always very respectful (and wary) of cyclists, but I'm not sure that criticizing a driver for wanting to get to the Migros before it closes is fair if the cyclist is a dude just trying to beat his personal best between Adliswil and Sihlbrugg.

Why do about 80% of cyclists think that regulations (red lights, give way signs) don't apply to them? Cycle paths are just part of that. Legally, if there is a cycle path, cyclists are supposed to use it, but then they're supposed to stop at red lights too.

Which they totally ignore and then complain that they get run over

Nice figure. But i get the point... but seriously if 80% of cyclists ignored give way signs...i do not think there would be many left! The red light thing is just a bit of cheekyness though. I do not get it why drivers get all worked up about it. It is done safely, otherwise, again we go back to my previous point about, if not being squashed and no longer a cyclist!

So why is the drivers choice of not leaving earlier enough and not being rushed to get to the Migro trumps Mr WanabeArmstrong choice of sticking to the road?

People need to chill out!

Really? In which cantons? .

Really? 80% of cyclists go through red lights, get run over, and complain? Really really?

I ride my bike on the roads if I must (use roads not my bike) and am happy to use cycle paths when possible so me an mine stay nice and safe. Yet on my way home in the car tonight, I experienced the empty cycle path but 2 lycra clad types, with iPods, on no doubt very expensive treaders were side by side yakking and totally and completely oblivious to the back log they were creating. Note to said cyclists... you aint doin' even close to the speed limit, get a room and get in the cycle lane. I could have sworn Beat Von Lederhosen in his Merc actually threw something at them as he passed... I just settled tutting and looking all Swissy superior... and cleaning my windscreen as I passed

Some "cycle lanes" are difficult to access. Some expect you as cyclist to drive down 10 meters and the UP again and therefore are useless. Some do NOT have exits where needed

In short, quite many of them are completely useless

Legally, you must use a cycle lane if present subject to a fine (don't recall the magnitude - probably 80 CHF). I expect that his law is basically unenforcable as there are a myriad of reasonable excuses why you might not be on the cycle path.

Personally, I choose whichever is the safest option for me. Probably cycle path 70% of the time but for the remainder on the road due to pedestrians, bad surface, blind junctions, detours etc. There are a lot of times where the road is a good deal safer at av 40kph on skinny tyres.

Cyclists and motorists need to respect each other and remember that the most important thing is getting from A to B safely.

Unfortunately, a small proportion of idiot cyclists and idiot motorists create a good deal of tension and animosity between both groups of road users.

I am actually glad that serious cyclists going 40kmh are smart enough not to share the bike lane with my children biking or walking the dog. It is much safer when they are on the road.

I believe the marked cycle lanes at the edge of roads (not dedicated separate cycle ways) are a waste of time and should be removed because:

1. as cars do not usually drive on this area of the road they fill with debris like small stones, thus making cyclist avoid this rubbish and swerve
   
2. the drainage grids are dangerous for cycles and again cause rider to come out round them
   
3. the increasing use of central pedestrian refuges mean that these lane actually end round these refuges while motorised traffic is forced in to where the cyclists are riding
   
4. the lanes encourage over-confidence with cyclists who can believe they are safe, but are in fact just as vunerable