planetary for the axle?

[mike75925]

ok, it is starting to make sense. the rotaries are said to be low torque, but high revving.

 

[TurtleMann14]

so they trade rpm for torque

same thing a transmission does

 

[mike75925]

torque for rpm

 

[TurtleMann14]

na, its rpm for torque

the engine is high revving, so they reduce the rpm for torque


think about how fast the axle spins compared to the speed of the engine...

say the engine turns 2k rpm and has 5ft lbs of torque

now, we will say the axle will turn around 600- 800 rpm that means that the torque though gearing will be increased to ~15 ft lbs 3:1 ratio

 

[mike75925]

you are familiar with the wankel right?

 

[Kaptain Krunch]

You can't get more torque without sacrificing speed, and vice versa.

 

[TurtleMann14]

that was supposed to be can't right?

somewhat familiar with them
they turn pressure in to speed yes
they have a large surface area generating a large amount of pressure

 

[mike75925]

what?

 

[Kaptain Krunch]

that was supposed to be can't right?

Yea, it was and its fixed.

 

[TurtleMann14]

in the wankel engine, the "crank" is spinning 3 times faster than the rotor. it also has 1/3 the torque at the crank

but though gearing, you gain that torque back and loose rpm

 

[motor_head]

remember you can't get something from nothing
no matter what you use to do the gearing be it chain belt gears it does the same thing if you did 2-1 chain and 3-1 gears it's 6-1 no different than just doing 6-1 chain only
only thing you going to change is more friction

 

[mike75925]

everything including nothing is something. who would have ever thought felix knew anything. he was sure enough to put his name on it and wankel lives on.

 

[motor_head]

didn't mean it like that just that you can't make more power you can give it more bottom or top end just not both by adding complicated gearing

 

[mike75925]

what is a multi-speed transmission then?

 

[motor_head]

is the threat about a multi speed or single, if you want to make a multi speed tranny then it will gain alot even a 2 speed
you can't gain anything with what your attempting that isn't just overcomplicating things

 

[TurtleMann14]

transmissions just make the most of the power band of the engine

they don't add power

 

[mike75925]

don't they? they add torque and add speed above and beyond what the engine is capable of.

 

[TurtleMann14]

nope, they add torque in low speed situations and add rpm in high speed situations

its a trade off between low and high speed as well as torque

 

[mike75925]

it seems we may be saying the same things, just with different wording. if you take a 80cc engine and remove the tranny gears running the output directly from the clutch hub, you will have a nice amount of torque, no speed to speak of. now if you put the gears back in and utilize the normal output shaft, you may get better or worse torque, but your topend speed (depending on gearing and amount of gears) will be x times more than the previous setup.

 

[TurtleMann14]

normally a transmission runs 1:1 in top gear, unless it has an over drive

if you run the engine straight to the wheels you will have lots of speed and hardly any torque

the gearing amplifies the torque as a loss of speed