eli5: Why does a CVT transmission still “shift” if it can be in any position and move seamlessly as they say?
In: 579
Because people are stupid and complained when CVT’s behaved like CVT’s ….
As an engineer I despise this fake shifting. It’s worse performance, worse comfort, and adds wear and tear. At least let me turn it off ffs…
Picture a set of stairs. Normally you would walk on each step to get to the top. Or bottom. But with a CVT. We are walking up stairs. Say you want to get to the top of the stairs faster. What do you do? You propel yourself with more inertia to skip a few steps to the top. Or maybe you want to skip many stairs on the way up. So, you jump skipping even more stairs. Those skipping stairs are the so called fake shifts on a CVT. The belt is jumping up the cone or skipping stairs. Once it finish the jump. The rpm’s drop back down and it continues its walk up stairs. But what about down? Same thing just backwards.
Since you’ve already noted that your Kia Sorrento does *not* have a CVT, I’ll just add that my 2015 Subaru Forester *does* have one, and it doesn’t do any weird fake shifting, unless I put it into low mode for engine braking or going up crazy steep gravel roads. It has weirded me out for driving regular automatics, though thankfully not for standard shift cars, since I spend a lot of time in places where those are the usual for rental cars.
You are correct. The entire point of a CVT (other than cost) is that you can run your engine at the RPM it is most efficient and powerful, and the transmission will take care of any rpm changes that need to happen during driving.
But that means your car sounds different from what people are used to, and they don’t like it. So car manufacturers cater to the average car buyer, who generally is an idiot. Now we have shifting CVTs.
See also: touch screens in cars.
Keeping the engine at 4000rpm constantly doesn’t sound or feel as fun so they program it to be inefficient and to wear out the parts faster so it revs a bunch and fake shifts to make it sound cool and feel fun
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