[M105]

Originally Posted by Mike Tee

My reasons are in another thread but I will reprise them here.

When accelerating briskly in the B 200 CVT, the engine sets up at a constant 4000+ RPM and makes a racket like a 1976 Renault 5 for about 10-15 seconds, until it hits the desitred speed (say 100 km/h). The B 200 engine is coarse and unrefined at anything much above 3500 RPM - whether the transaxle is manual or automatic - and with the manual 'box it is possible to keep tis engine in the nether reaches of the RPM range, even when accelerating briskly. Not so the CVT (unless you shift it "manually" with the slap-shifter, which has seven virtual gears, so you'll be slap-happy before you know it).

The reason the CVT sails up to the high RPM is that the B 200 develops its peak torque at a high 3500-4000 RPM, which is where the engine begins to sound coarse and gets noisy. The CVT will always do this, get to the heart of the torque band when accelerating moderately.

Even a pepère driver has to hammer it once in a while, to merge onto a freeway for example, so it is not a moot point.

Other unrefined aspects: the CVT hunts and makes the car wobble (as though the car has warped brake discs) a bit when slowing to a stop, as though the CVT is "gearing down" through the pseudo-gears. I found that annoying and surprising. I am sure it's unnecessary. It's almost as though there were wear points on the variable diameter drums that were causing this, but the three CVT cars I drove had few km, so that shouldn't be it.

I also didn't like the CVT's tendency to use engine braking on downhill runs, where in the manual car I'd be running out in 5th to keep the fuel consumption to zero for a longer distance and time.

Sure, many if not all of these problems can be overcome by shifting the car manually through its seven virtual gears, but then: why buy an automatic if you need to shift it manually (and 40% more often than the manual on the B 200) to enjoy a smooth, brisk and serene ride in all road conditions?

The reason the CVT comes off better in the Turbo is that the Turbo has a massively wide peak torque band, 1850 to 4850 RPM, so even when accelerating hard, the CVT only needs to take the engine to maybe 2000 or 2200 RPM when moving off. Even under hard acceleration, I found that it stayed around 3200 RPM. The other things (downshifting and wobble) still seemed to be there, but I would find it much easier to live with.

No offense intended, these are just my observations when driving the cars. I have read media reviews that essentially say the same thing, and the British media reports call the B 200 engine unrefined and recommend in favour of the CDI diesels.

i think it may come down to driver-style. i find even entering the highway very little need to rev high, but on occasion when needing to make haste the engine revs temporarily and makes some vibes (it is under your feet) but is quite the non-irritating kind. this tranny is the best auto i have ever used imho. i do wish though that we could buy the diesel here in canada as i woul choose it in a heartbeat.