Aerodynamics vs weight?,

[Itchy]

To fuel efficiency whats more effective ? , in one of my terribly random moments, I thought hmm what would happen if you put one of those bullet type fairings (like from the world's fastest Indian or very old style racing unlike WSB BSB or moto GP where they are banned) onto a CG125, since the CG is economical cus it weighs very little but enclosing it gives much better aerodynamics ,
but would add weight probably quite a bit compared to the bike as a whole.

I'm just bored and probably after a method to spite the Chancellor , darned running 2 bikes on petrol is costly! (esp since the CBR is somewhat thirstier than the NTV).

Any thoughts?

Ta
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Spain 2008France 2007Big one 2009 We all die. The goal isn't to live forever, the goal is to create something that will. In the end, your life will flash before your eyes. Make sure it is worth watching.

[Walloper]

I would hazard a guess and say...
Aerodynamic efficiency would be better than shedding weight.

Weight would be a limiting factor to get up to top speed. Though once there you only need maintain it. Less energy to maintain than to achieve.

But when you spin a weight or move it in a different direction to the direction you wish to go in you will have losses.

Problem on a bike and drag coeficient is that you are limited by the dimensions of the vehicle.

You should go outside and count buses if your bored.

There is a record for a guy on a push bike over 130mph..... (Not sure of exact figure)

But slipstreaming behind a fast car towing a big fk off board.
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[Pete.]

For top-speed, aerodynamics is everything. Weight means very little apart from increased internal friction (bearings, tyrewall flex etc) and more momentum to overcome so more time to get there.
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a.k.a 'Geri'

132.9mph off and walked away. Gear is good, gear is good, gear is very very good

[Dazbo666]

...so I should eat less pies and get myself a body suit???

I don't think anyone should be subjected to that image LOL
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1st bike (Sept'06 - May'10) : 1991 GPZ500S / Current bike (since Nov 2009) : 2003 Suzuki Bandit 600N
Word of the day : DILLIGAF

[kart racer]

Aero will really only have an effect from around 70mph. I would guess below that the extra weight of the aero aids on a low powered machine such as a cg125 would outweigh the benefits.

over 70mph aero can really start to count so it could start to offset the weight you have gained from the extra bodywork.
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Winners never quit, and quitters never win

[wikiwiki]

I'm a very basic person and i can only offer a basic incite,

If you're on a 125 and only pootling around town at 30-40 mph i'd say that a weight reduction would help more.

Remove the battery and engine, that fuel tank would be heavy with all that fuel in too, that'll make it nice and light.
Titanium clock surrounds FTW.

Incidentally, has anyone seen petrol at a pound a litre yet?

Amazingly i saw an esso 20 yards from old street roundabout (yeah, in the city!!) doing 93.9 per litre yesterday
Can't even get that in the supermarket stations.

[Pete.]

[wikiwiki]

[TheShaggyDA]

I think that considering the difference a simple air deflector makes when put on an artic, you'd get a better improvement sorting the aerodynamics first, then think about shedding weight.

https://img.alibaba.com/photo/11572258/Isuzu_Wind_Deflector.jpg
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Current: CB500 Previous: CB100N, CB250RS, XJ900F, GT550, GPZ750R/1000RX, AJS M16, R100RT, Enfield Bullet

[i:6e3bfc7581]But still I fear and still I dare not laugh at the madman...[/i:6e3bfc7581]

[wikiwiki]

[Kickstart]

Hi

For efficiency it will depend on the use of the bike. Round town, accelerating and braking the extra weight would be costly and the benefits nominal. At constant speed it is the other way round.

All the best

Keith
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Traxpics, track day and racing photographs - Bimota Forum - Bike performance / thrust graphs for choosing gearing

[stinkwheel]

Consider then that 1960's 50cc TT race bikes were fitted with a dustbin fairing made of aluminium. This was considered to be a worthwhile exercise despite the (comparatively) massive increase in weight.

EDIT: Since you seem to be in a silly frame of mind, why not subject the theory to empirical testing. You will need a long, empty, level road and something heavy. I'd suggest a container full of water strapped to the back (maybe 10l to make it worthwhile? You could spend a hell of a lot of money making your bike 10kg lighter). Get the bike flat-out and dump the water, see if you go any faster.

Now get it flat out sitting bolt upright then adopot the full 'racing prone' position with your feet on the rear pegs, chin on the clocks and left hand behind your back, arch your shoulders slightly. See if you go any faster.

This should give you an idea of the relative benefits of weight loss vs drag reduction. From personal experience on my H100, I reckon moving from sitting to full prone is worth 5mph minimum on your top speed.
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I did the 2010 Round Britain Rally on my 350 Bullet. 89 landmarks, 3 months, 9,500 miles.

[gmanxiii]

you thinking of putting fairing back on your ntv?
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