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Locost BEC centre of gravity
Alez - 3/3/04 at 09:26 AM

Correct me if I'm wrong, but sice the other day I was told that the weight of a Fireblade engine is something around 80 kg, I'm starting to think that the position of the centre of gravity in one of these, whith driver, can't be too wrong compared to a "proper" mid engine configuration!!! So, does that mean that all this mid engine business makes a lot less sense when applied to BECs?

Cheers,

Alex


JoelP - 3/3/04 at 09:33 AM

i think even car engined 7s approach 50 50 weight distribution, so mid engined isnt as important as it is in a full weight normal car.

however, i think 50/50 might be a bit of a myth anyway, why should the weight have to be precisely over both axles? afterall, the steering isnt equal on both...

less weight on the front end (maybe 40/60 front to back) will make better turn in i guess, and good wide rear tyres will help prevent the back end doing a pendulum impression...


Alez - 3/3/04 at 10:27 AM

Yes I have the same feeling. I guess that the answer would be: Take the example of a highly optimized race car (namely F1 for instance) and find out what the weight distribution is. That should be pretty close to optimum!!


Alan B - 3/3/04 at 02:12 PM

Guys, in terms of weight distribution I'm sure you are right and especially with bike engines.......for me, however, the big appeal of mid-engined was the sheer volume of FWD units that can be transplanted behind the driver....

Hmmm?....doesn't really answer the question or help at all does it?..

[Edited on 3/3/04 by Alan B]


Spyderman - 4/3/04 at 04:29 PM

Mid or rear engine has many advantages over front engine rear drive.
One of the main is packaging, just like front engine front drive. More room for occupants and luggage when evrything is packaged together.

With a two seater sportscar there is very little in it between front or mid engine. However when you are talking race car it is a different thing altogether.
The weight of the driver becomes a major factor in setting up the car. This can be balanced by positioning the engine behind or even alongside the driver. Much harder to do with the engine in front.
There is also the matter of centering all the heavy items in the centre of the car to avoid the dumbell effect!

Terry


crbrlfrost - 7/3/04 at 05:15 AM

For a bike engine, I would think mid-engined layout would definitely be the way to go. But I'm biased pretty close to symetry, a sickness I have. F1's are somewhere in the neighborhood of 41-45% front weight bias from what I've heard, and it offers several advantages. More weight on the rear for acceleration, and more even braking loads when some of that transfers forward. Probably has descent trail braking characteristics with perhaps some mid-corner understeer. But hey, dampers and bars can change lots of things!


Noodle - 7/3/04 at 09:51 AM

Gordon Murray reckons the original Elan was the best handling road car of all time. Although front-engined RWD, the weight distribution was 48F/52R.

Skinny tyres too

Cheers,

Neil.