2007-01-21 20:54:29 · 3 answers · asked by Anonymous in Cars & Transportation ➔ Other - Cars & Transportation
Have a look at:
http://en.wikipedia.org/wiki/Variomatic
Invented by Daf subsequently used by Volvo in the 300 series cars and then widely used in twist and go scooters and the odd Ford.
2007-01-24 01:34:47 · answer #1 · answered by rookethorne 6 · 0⤊ 0⤋
Hi
Rather than gears, a CVT has a conical drive and a drive belt.
The drive belt slides up and down the cone, thus giving the different drive ratios which we would normally achieve by changing gear.
It is a smooth, seamless operation, and if the drive belt lasted more than 5 minutes it would be great, but it doesn't in a lot of cases, and a replacement drive belt can run into the £900 arena because the box has to be removed and stripped!!
I know of a number of cases where the belt has only lasted between 19000 and 26000 miles.
The explanation for this quite simple. The CVTs were once used on the Leyland Daf trucks, and in those days the belts were constructed of a good strong rubber, and they lasted very well.
One day, someone with nothing better to do than sit with one finger up his nose and another up his @rse, decided that maybe a metal belt would be a good idea, and there you have it, a metal belt sliding around inside an auto box at thousands of RPMs. Bound to last.......... NOT ON YOUR NELLY!!!
I do believe that CVT equipped vehicles are NOT allowed to be raced because the ratio change is instant whereas normal auto boxes and manual boxes take a little time to select the desired gears, which gives the CVT the upper hand. Strange but true!!
Best wishes
Geordie
2007-01-21 21:42:58 · answer #2 · answered by Grizz 5 · 0⤊ 0⤋
Instead of defined gears like at the back of a pedal bike, going from the smallest cog (Top gear) to the largest cog(1st gear) a variable transmision would have a cone instead of each gear. The drive can slide anywhere up and down the cone depending on what gearing is required. No gear change is felt as the gearing is constantly changing up and down the cone as required.
Thats a fairly loose description...but you can maybe get the idea.
PS you dont actually get that on pedal bikes!
2007-01-21 21:02:59 · answer #3 · answered by ian r 3 · 0⤊ 0⤋