Quote:
|
Originally Posted by zimbop
I get that in my CTV occasionally too. It seemed to happen at least once per trip for a couple weeks, then it all but disappeared. I sometimes think it's a delay in the car re-engaging the tranny after coasting, decelerating or stopping. Like it's running free for a half second before engaging, maybe a little like dumping the clutch or revving in neutral and dumping it into D. Something like that. It hasn't happened for a while though and I can't think of anything that changed to blame it on.
|
I believe that essentially, that is what is happening. I have seen diagrams of the Honda CVTs and from what I understand, they have a computer-controlled clutch that kicks in at low speeds. In the HCH-1 at least, I can feel going into auto-stop, the car starts to glide a bit with very light brake pressure (the clutch releasing).
If I, say, stop at a stop sign, it begins to auto-stop, then I give it a lot of gas for some reason (say I'm going up a hill, or want to turn onto a busy road or something), sometimes the engine will rev a bit before the clutch syncs, exactly the same as revving in N and dumping into D. If you give it very light gas, or say, coming out of a red light, release the brake early and let the engine idle for a moment, the tranny should engage fully with no problem.
Quote:
|
Toyotas CVT if I remember right has two varible pullys which will spread the load over more of the surface area of the pullys. There both always moving looking for that perfect load curve and the tranny has less horsepower and torgue to deal with over all. So it may well last longer.
|
Honda's CVT I know has two variable pulleys,
here is a page describing the CVT in the Insight which I presume is the same as the one in the Civic.
The Toyota CVT is actually a fixed-gear-ratio transmission using planetary gears as a differential to split engine power between the drive wheels, and a generator, which directly powers a second motor (in addition to some power coming from the battery as well). This produces a blend of the engine's torque at high RPMS and the motor's torque at low RPM. By varying this ratio, they get a CVT-like effect without actually any mechanical shifting. Ideally this transmission should have the least amount of problems, but the drawback is the inefficiency in the conversion from mechanical to electric power and back. This eCVT (iirc electric CVT) should also scale to work for just about any size motor as well, provided the electric motors are also scaled correctly.