Drafting busses and lorries

TheBrick(Tommy)

It is to do with the center of gravity being high on bike that limits braking power of a bike. The friction which can be archived between the fount tyre and road is greater than or equal to the amount needed to allow rotation about a point (the point in question being the contact point of front wheel to the road surface). DUe to the longer nature of a tandems and cars (also the lower center of gravity) the amount of force required for the car / tandeml to pivot about the contact point it greater than the maximum friction that can be achieved.

Right. Having thought about it some more (not that I suppose anyone cares at this stage), I've come to the somewhat surprising conclusion that the height of your centre of gravity doesn't matter at all. What counts is the diameter of the front wheel and how far back your centre of gravity is. Your maximum deceleration as a fraction of g is (distance c.o.g. behinde axle)/(front wheel diameter). I have diagrams. Yes, I do have better things to do...

no... that's not right either. i was doing statics around the front axle but there's a net acceleration so we need to balance moments around the centre of mass. the right answer is maximum deceleration is
(distance behind axle)/(height above ground). which is more or less what we said in the first place. I'll go and do something else now.

Aw, I care. I just don't want to have to think about it. I want to be told definitively who can stop faster.

The teenage Robert Millar used to ride behind buses from Glasgow to Kilmarnock and back. He's the king of the drafters. :-)

Skullhead [quote]TheBrick(Tommy) [quote]Skullhead Pratts who do this deserve to get mashed.

I am not condoning the actions but deserve to be crushed!?[/quote]

well ok perhaps a little harsh!

but its not big or clever.[/quote]Like a dwarf with learning difficulties?

just a quick comment to say when i was at school i used to get the bus home and a friend of mine used to ride his bike, drafting behind with hardly any distance between him and the bus. one day the bus slammed on the brakes suddenly and he went straight into the back, then landed face first on the road. looked worse than it was, but could have been nasty. so i'd never draft a bus driver personally.

Bus drivers aren't fast enough.. you really want to try it behind the bus..

drafting in style…

YouTube - Broadcast Yourself.

^ Mind you, I heard Linford Christie had recently been hired by Arriva.

Only uphill behind a bus on one regular bit for me.

Anything else is too nuts - I'm too sensible / much of a jessie. S

^^^ great film that.
but his front quick release lever is all wrong.

what film is that, i need seen.

chris crash what film is that, i need seen.

Breaking Away

what, you actually want a name instead of some vague recollection of having seen it?
...
[consults t'internet]
...
Breaking Away.

I gave it a go drafting a bus this afternoon going towards Putney from Hammersmith. Makes quite a difference if you're riding into the wind but a quite dodgy not being about to see if any potholes are coming up, or if the bus suddenly stops. And you get all the nasty fumes!

15 years ago I drafted a hatchback. I still have the scar to prove that car brakes are better than those fitted to my bike.
The frame was wrecked, but will be reborn/restored soon thanks to Barry Witcomb and Ebay.

drafted a 4x4, some superstar thing with spinners, it kept me out of the head wind and snow, was a little dodgy, i actuly feel safer skitching, cuz you can just let go and fly past, or push back and stop.

i've never had the guts to skitch. always think something is going to happen and cause me to get knocked under!

Like in London when cars veer sideways every 100m to dodge some blind fsck pulling out or another numpty pedestrian in twatPod mode..

You can get a good draft from a safe distance (assuming your brakes work) but skitching is just gonna end in tears, especially since you don't know the driver.
Nothing goes fast enough in London and outside London most traffic is too fast anyway.

Fixed wheel skitch? Is he avin a laff? Are you avin a laff?

@hippy - twatPod:

I thought I was the only person in the world who hated them. Especially cyclists wearing them... grrrrr

I skitched behind a truck up the majority of Broadway in NYC. Held onto a rope and was a good 8 feet behind, sun was out, chilling and joking with my mate who had held onto a bus, when the brakes went on, 15-20 mph straight into the back of it.

it was fucking cool!

http://www.youtube.com/watch?v=BmpxJWAJbFM