So I can do both 1 MPH and 70 MPH with my one gear? That's one Hell of a gear I got there.

 

i'm not familiar with a cvt tranny. it sounds to me kinda like a torque converter. does the sprocket (if that's what you call it) that comes out of the motor close in on the belt as the engine revs higher, and the second sprocket spring loaded? if so, the gear ratios ischanging the faster the engine revs higher. as the first one closes in, it becomes larger, like this-> )(. and the second sprocket opens up and gets smaller. so the gear ratio changes. that's the experience i have w/ a torque converter. is that about the same as the concept behind the cvt trannys?

 

more or less, yes thats a lot the way it works, there are two different shaft type things, not exactly sure what theyre called. theyre skinny on one end and fat on the other.

Take a look at this drawing:
CVT drawing
bare with me, i made that in MSPaint in 5 minutes...at 12:15AM.

THere is a belt of some sort connecting the two shafts, that constantly changes positions depending on the amount of throttle you give. On a CVT quad, you can goose the throttle from a stop and it will be near redline the whole time, all the way up to top speed, this is beacuse the 'belt' is at the part of the shaft that gives it the most power to the wheels, which would be the fat part of the output shaft...i think i may have drawn the shafts backwards but i dont feel like going back and redoing them. CVT stands for continously variable transmission, meaning that the belt is always moving with the varying amounts of engine output....hence NO GEARS.

You might try looking on honda's or polaris' websites, they both use CVT's (honda uses them in the hybrid civics) for more info.

 

cvt
Heres an interesting article on the cvt transmission.

 

yea, hondabuster, that's exactly what i'm talking about. i understand how it works now. so for kevinm, they don't have "gears" but they do change gear ratios depending on engine speed and torque required to move the car.

 

yea, thats what i was trying to get at lol

 

quote:
yea, hondabuster, that's exactly what i'm talking about. i understand how it works now. so for kevinm, they don't have "gears" but they do change gear ratios depending on engine speed and torque required to move the car


And just how do you suppose they change gear ratios? Think maybe it has to shift up and down to change those gear ratios?
To simplify for those of you not familar with the CVT, it works similarly to a 10-speed bicycle. You have sprockets/pulleys at both ends. The belt/chain rides up higher on one end and lower on the other to shift up and vice versa to shift down. Unlike a bicycle, it doesn't have a certain amount of gears, it has many, many diferent gear combinations based on how high it is on one pulley and how low on the other.

I've been tuning CVT's for the past five years. If you don't think they shift up and down then you don't understand how they work.

 

yea, i see where you're coming from. the do literally shift gears, but they don't "shift" like we're thinking, and they don't have the sprocket type gears. that's all we're saying. i agree the do change gear ratios, but they don't shift gears the same way we're talking.

 

Kevin, you might be in a losing battle[img]i/expressions/face-icon-small-happy.gif[/img][img]i/expressions/face-icon-small-wink.gif[/img]