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CC compared to V6/8/12 ect.

Discussion in 'Technical and Troubleshooting Torque' at netrider.net.au started by shady_knife, Apr 8, 2009.

  1. how does one go comparing bikes engines with car engines? is there a set formula? or is it guess work?

    just wondering how to stack bikes up against cars ect.


     
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  2. there's no real way to do it

    easiest way to determine power is by bhp/tonne or kw/tonne

    a vehicle can have 10000000bhp, but weigh 200000000tonne

    meanwhile another can have 180bhp, but weigh 200kg
     
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  3. Power/Weight ratio is the best way. Also the drive type of the car, a front wheel car wont be able to put the power down as well as a real wheel or 4WD car.
     
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  4. Well i will say last night the V12 Mercedes i was behind was an absolute weapon. On the street the RS4, GT3's, R8's etc are blindingly quick. All traction, instant power, big brakes, expect to get munched on the street.

    You could compare fairly on a runway. Anything less and it's all down to the rider/driver. 130hp in a bike is enough power to be up there with exotics for acceleration but only just. Step up to your litre bikes and only severely worked cars will come close.
     
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  5. just wait till FLUX sees this, he will write up a full essay to answer your question, y x z= sumfin square
     
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  6. datz ezy 2 anzr bikez r mor fun. carz r 4 l00zrs

    wot u tlkn sht 4?
     
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  7. only shit here is from your last comment :roll:
     
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  8. Now now, settle petals!

    As for cars V bikes, power to weight and torque to weight are two good measures, Rear wheel figures are best.

    And even better, real world figures are better - 0-100kph, 100-200kph, 100-0kph, Phillip Island in the dry.
     
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  9. truth be told, ye cannot compare lap times. None of us have a tame professional race driver to drive each vehicle each time. I may be faster than say Goz in an Audi r8 but Goz may be faster in the ferari, I could sneaze on the timed lap and loose a ridiculously small amount of time, which would make the comparison whack.

    Anyone willing to supply said R8 and Ferrari, Goz and I would appreciate it ta.
     
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  10. dont have to ask me twice :grin:
     
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  11. :LOL: :LOL: :LOL:

    hook line and sinker
     
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  12. Never suggested; dynamics suggest a super car will always be quicker in the turns then a super bike. however, telemetry data surely can provide a fair indication under similar conditions at identical points, no?
     
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  13. I remember MOTOR magazine doing an article of a Porsche (with a race driver) vs GSXR1000 at Eastern Creek. They had telemetry data and you could see the Porsche out braking the bike by a long shot and i believe the corner speed was higher.

    Acceleration and straight line speed was all bike and it only 'just' lapped quicker than the Porsche.
     
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  14. And of course, the almighty 1/4 mile (0-400m).


    Power/weight ratio is my personal favourite for ballpark-estimating how fast a vehicle accelerates.
     
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  15. I think you're all over-thinking it: the question was just about capacity.

    Pretty much everything (except Harleys) is measured in metric units now, so a 1200 cc bike has a capacity of 1.2 litres. That's comparable to a small car, which might have a 1.3 or 1.5 litre engine. Lots of V6s are around the 3.0 to 3.5 litre capacity, and V8s take it up to about 5 litres.

    The capacity is not the most useful comparison, as others have said, and power/weight ratio is a better one, but just in terms of direct comparison, one cc (cubic centimetre) is the same thing as one mL (millilitre), so there are 1000 cc in one litre.

    (Older cars were reported in cubic inches, and Harleys sometimes still are. An inch is close enough to 2.54 cm, so a cubic inch is 2.54^3 = 16.39 cc. So a 5 litre V8 is 305 cubic inches. Common Australian V8 sizes were 308 and 350/351.)
     
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  16. engine capacity, max rpm, piston stroke, number of cylinders, head flow and internal resistance all affect power output. cars and bikes have different engine requirements.

    worst engine ive ever seen on a bike: V8 boss hoss


    power to weight ratio is a bit flawed when it comes to bikes vs cars as well
     
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  17. Yeah, for a given power:weight, a car has a higher top speed than a bike. This is because cars are, comparatively speaking, more aerodynamic than bikes.

    This was confirmed when a guy on fireblades.org tried to highway-race some top of the line turbo 500hp+ porsche cayenne in his 954rr. Over 200km/h, the SUV was (allegedly) pulling away.

    Thats why you need to chuck $ or value into the equation :LOL:
     
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  18. Yep, and the only thing that trumps aerodynamic drag is absolute power.

    This is a disadvantage for lightweight sportscars like the Lotus Elise/Exige, MR2, etc - They have great power/weight but not much absolute power, so after 150+kph their straight line performance dwindles compared to a twice-as-heavy, twice-as-powerful car.
     
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  19. No idea what you said in your post shady_knife, but
    god damn ... couldn't take my eyes off your avatar :oops:
     
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