My Theory on Bikes...

godinman

godinman

godinman

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...the ones with pedals.

Most times on my way to work I encounter several bicycles, usually I have to slow down to near their speed, and then accelerate past them quickly.

Now most people biking to work wont be biking further than a half hour car journey so I'll use that as a basis for my empty calculations.

What I'm thinking is that any 'green' saving made by the bikes is outweighed by the extra fuel and co2 used by the hundreds of cars forced to overtake.

Anyone with better math skills than me fancy working out the amount of co2 and fuel used in an average b-road half hour car journey vs the amount of extra co2 and fuel used by all these over taking cars? Say 500 or so (maybe) and all probably driving a generic 1.9tdi.

I know this is a pointless calculation as there are more reasons to bike to work than to save a few polar bears, but it's be good to wipe the smug smiles off a few peoples faces...

Meh, feel free to flame me:D
 
My car is small enough to pass them without crossing the white line so they don't bother me.
I am a Live & Let Live kind of guy though. :cool:
 
Somethimes I encounter no cars on my ride to work or the industrial estate when I ride through there.

Often it's just a couple. :p
 
It's not about the Co2 saving! It's just cheaper to run a bike than a car?

It means you can cycle to work on the bike and have a nice car to have fun in!

Right now the police are getting cycle scheme and are spending thousands on new bikes so the roads will be even more full!
 
Back from work now..

Yes, thanks for all that as I mentioned I know there are lots of other reasons for riding to work, and I'm sure some people in particularly tiny cars, who don't mind squeezing in between a soft, fleshy humanoid and 1.5 tonnes of steel can pass without braking, but I was just wondering if the environmental reasons people sometimes state are actually valid.

Anyone know how I would go about working this out? Will google it I suppose, thought there might've been a passing environmental scientist/mathematician around to help...
 
Always amazed how many cage drivers have no idea about the width of their car, usually going way wide when trying to pass bikes.
 
oap said:
Always amazed how many cage drivers have no idea about the width of their car, usually going way wide when trying to pass bikes.
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I'd quite happly pass 2 inches from your handle bars at 60mph if you would prefer that. "Cage" drives go way wide to be considerate and to give you 2 wheelers a bit more room to make erratic movements.
 
Never really had an issue getting past cyclists without slowing down. Only on a particularly narrow road where cyclists don't tend to be would it cause a hold up.
 
Yes, on wide clear roads it's fine. But surely on 90% of roads, during rush hours, on the way into towns and cities, most of the time a car is coming in the opposite direction, so you have to slow down, wait behind the bike and then accelerate back up to speed.

This is what I find at least, although I suppose Wolverhampton is a sprawling metropolis after all, with 15 metre wide roads and only 3 cars so maybe it's different there.

Meh, I take it no one knows this sort of info of hand, will look it up myself.

Mods, feel free to close..
 
oap said:
Always amazed how many cage drivers have no idea about the width of their car, usually going way wide when trying to pass bikes.
Click to expand...

What gets me is the ones that sit right on your back wheel because they're too scared to overtake. Fair enough if its a bendy road but when its a clear straight road it is really annoying and sometimes scary!
 
godinman said:
...the ones with pedals.

Most times on my way to work I encounter several bicycles, usually I have to slow down to near their speed, and then accelerate past them quickly.

Now most people biking to work wont be biking further than a half hour car journey so I'll use that as a basis for my empty calculations.

What I'm thinking is that any 'green' saving made by the bikes is outweighed by the extra fuel and co2 used by the hundreds of cars forced to overtake.

Anyone with better math skills than me fancy working out the amount of co2 and fuel used in an average b-road half hour car journey vs the amount of extra co2 and fuel used by all these over taking cars? Say 500 or so (maybe) and all probably driving a generic 1.9tdi.

I know this is a pointless calculation as there are more reasons to bike to work than to save a few polar bears, but it's be good to wipe the smug smiles off a few peoples faces...

Meh, feel free to flame me:D
Click to expand...
I am an environmental engineer and making calculations like this is very valid in making environmental decisions on what is the best environmental choice. Your argument is valid but you'll probably find that the bicycle still has the gain overall, even if you factor in the extra food the rider has to eat and the fuel to accelerate.

The sad fact is many transport studies show that big gains in CO2 emissions are by drivers actually driving properly, anticipating situations ahead and not driving on and off the throttle. You've unfortunately just added to the statistics by admitting that you don't do this.

The other thing is you're assuming cyclists are doing it for green reasons. Why would they be doing that then? Nobody else does. It's not why I use a bike to get to work and I'm an environmentalist :confused:
 
Jonny69 said:
I am an environmental engineer and making calculations like this is very valid in making environmental decisions on what is the best environmental choice. Your argument is valid but you'll probably find that the bicycle still has the gain overall, even if you factor in the extra food the rider has to eat and the fuel to accelerate.
Click to expand...

Hmm, I suppose it depends on the amount of cars overtaking versus the distance traveled by the bike..

The sad fact is many transport studies show that big gains in CO2 emissions are by drivers actually driving properly, anticipating situations ahead and not driving on and off the throttle. You've unfortunately just added to the statistics by admitting that you don't do this.
Click to expand...

You can only anticipate so much, if you can time it correctly of course you can overtake without changing speed, or at least only doing so smoothly - ie coast to a slower speed, the oncoming car passes and then you gently accelerate past. But a lot of the time I find when I'm out and about that I have to wait for a few vehicles to drive past so have to slow down a lot, or I come across a bike after a blind bend and have to slow down quickly etc

The other thing is you're assuming cyclists are doing it for green reasons. Why would they be doing that then? Nobody else does. It's not why I use a bike to get to work and I'm an environmentalist :confused:
Click to expand...

I'll point you to this -

there are more reasons to bike to work than to save a few polar bears
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That's me acknowledging that there are more reasons to bike than to save the planet, but some people do say that is part of the reason, or at least they use it to act smug. And you can have one of these back :confused: with one of these :p

EDIT - and thankyou for an actual answer!
 
Nine post J69.

As a cyclist, there is one part of Chelmsford where it's busy and the road is very tight in both directions and traffic builds up behind me quite quickly. Depending on how much I will normally pull over to let traffic pass particularly if there's a bus too but ony if it's safe to do so. Buses will nearly always acknowledge this jesture whereas drivers tend to be in their own little world somewhere..

Personally, I've never really thought about using the bike for environmental issues. For me it's part of my fitness regime, it's cheaper than parking at the station and certainly more reliable than getting a bus.
 
I'm a keen driver and cyclist. Cars are annoying when you're on your bike, bikes are annoying when you're in your car.

The current cycle lanes are pretty much useless where I am. If they could build better cycle routes which pick better routes in and out of town it'd be better for us all. As a cyclist I'd rather do an extra 1/2 mile on a cycle route than follow the major roads in rush hour to get where I'd going.
 
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godinman said:
Hmm, I suppose it depends on the amount of cars overtaking versus the distance traveled by the bike..
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It would be a pretty complicated bit of research. You'd have to observe behaviour, count the number of cars and work out a way of calculating or estimating the extra fuel per acceleration to do it exactly.

In terms of the comparison you'd switch to CO2-equivalent (CO2e) because the 'emissions' from the rider are a combination of methane from farts which is more a more potent greenhouse gas than CO2 (but in much smaller quantities) and CO2 from growing and cooking his food.

I think, as with many lifecycle studies, you wouldn't need to go to much detail on a study like this because the energy required for a bike journey is significantly lower than the energy required for a car journey, probably by a factor of ten or more. So basically, a load of cars overtaking a bike would never add up to the 'saving' that the cyclist has made by not using a car for his journey.

It's interesting, because the amount of detail required in environmental life cycle studies for decision making is something I'm researching at the moment.

godinman said:
You can only anticipate so much, if you can time it correctly of course you can overtake without changing speed, or at least only doing so smoothly - ie coast to a slower speed, the oncoming car passes and then you gently accelerate past. But a lot of the time I find when I'm out and about that I have to wait for a few vehicles to drive past so have to slow down a lot, or I come across a bike after a blind bend and have to slow down quickly etc
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I agree. I was more referring to the way people hammer the clutch off the lights to another red light, blindly accelerate up behind other cars before slamming on the brakes, nail it off roundabouts, way too much throttle when creeping in stop-start traffic, on and off the throttle on the motorway etc etc. Got a bit carried away :p

godinman said:
I'll point you to this -
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Oops, missed that bit completely :D

godinman said:
EDIT - and thankyou for an actual answer!
Click to expand...
No worries. From me you get environmentally correct answers, minus the sandals :D
 
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