[sigmabody]

Originally Posted by TurtleBoy

I think you mean the smallest radius wheels not tires. Often the smaller wheels will have a larger tire radius. For example, with the 20" wheels the radius is 14.87" while with the 22" wheels it is 14.71.

I do, yes; sorry I misstated that. You want the largest sidewall length, which is often correlated with smaller wheels (particularly if the vehicle has lower profile tires with the larger wheels), but certainly not always.

[sigmabody]

The second number in the tire size designation (eg: 45 in 275/45) is the aspect ratio, which is a rough proxy for the sidewall height (it's the percentage of the radius which is the sidewall). So technically a larger tire with a smaller ratio could still have more air between the wheel and the road, but generally the higher aspect ratio the more comfortable the ride will be over bumps (and the less surface area the tire will maintain while cornering at high g-forces).

That's my understanding, anyway.

Edit: TurtleBoy is correct: aspect ratio is to the _width_, not the radius.

[TurtleBoy]

Originally Posted by sigmabody

The second number in the tire size designation (eg: 45 in 275/45) is the aspect ratio, which is a rough proxy for the sidewall height (it's the percentage of the radius which is the sidewall). So technically a larger tire with a smaller ratio could still have more air between the wheel and the road, but generally the higher aspect ratio the more comfortable the ride will be over bumps (and the less surface area the tire will maintain while cornering at high g-forces).

That's my understanding, anyway.

It is the aspect ratio but the calculation for the sidewall height doesn't involve the radius. It is the ratio of the tire width to the sidewall height (sidewall height = width * aspect ratio / 100. So in the 275/45 example the sidewall height would be 123.75mm ((275 * 45)/100).

The third number in the tire size designation is the size of the wheel.

[jpw172]

I saw a YouTube video on this, and you can change the settings on the level of regeneration I believe…even turn it off if you prefer. I had a Tesla rental one time and the way they do regeneration is very jarring until you get the hang of it. BMW was very smooth and cutover to ICE from electric also was very smooth couldn’t even tell at first.

[jad03060]

BMW, at least in the PHEVs, does not have a menu adjustment for the level of regeneration. Now, different modes of operation do affect it, but within each mode, there's no menu control.

[jpw172]

Originally Posted by jad03060

BMW, at least in the PHEVs, does not have a menu adjustment for the level of regeneration. Now, different modes of operation do affect it, but within each mode, there's no menu control.

Maybe it is the full electric only… here is the one video.
https://youtu.be/vfKyiE5Z4kU?si=5iZnwGp1SzjvQ3IA

[jad03060]

Since it's all software controlled, BMW could offer user configuration of the amount of regenerative braking, but I've not seen it nor heard of anyone that found a parameter that could be tweaked via coding on the PHEVs.

[SwissBeemer]

Originally Posted by sigmabody

I do, yes; sorry I misstated that. You want the largest sidewall length, which is often correlated with smaller wheels (particularly if the vehicle has lower profile tires with the larger wheels), but certainly not always.

The circumference of the tyre is always the same (so spedometer doesn't have to be recalibrated, etc.) so smaller diameter rims always mean more air between the rim and the tyre since the outside diameter of the tyre always stays the same and just the inner diameter gets smaller.

[TurtleBoy]

Originally Posted by SwissBeemer

The circumference of the tyre is always the same (so spedometer doesn't have to be recalibrated, etc.) so smaller diameter rims always mean more air between the rim and the tyre since the outside diameter of the tyre always stays the same and just the inner diameter gets smaller.

Just for clarity, the circumferences are not always the same but usually within a % or so.

[mobsync]

Which driving mode offers the highest level of regen in the 50e?

[bono]

I understand you can't control regen power... that's a shame. The regen in electric mode is non-existent. They could given an option to change the regen level with the steering wheel paddle shifters.

[jad03060]

If you watch the power meter, you'll see that you do get at least some regeneration in any mode, just maybe not under the same circumstances.

Note on the PHEV X5, unless there's a fault, all braking is electronically controlled and a blend of both regeneration and the computer activating the hydraulic brakes. Only if there's a fault does the brake pedal actually directly activate the brakes mechanically.

[bono]

Thanks. I should not have said that regen is non-existent. It is disappointing.

[aaaaaaaaaz]

Feel 50e generative braking is very minimal to the extent you can almost ignore if you turn off the adaptive option

[jad03060]

BMW chose not to let the X5 be a viable one-pedal driving experience, whereas when I had an i3, it was. In fact, when originally released in the USA, it had so much, people new to it complained as when driven like an ICE, letting off the accelerator produced so much regeneration that it would easily throw you forward from the deceleration. It took me maybe 5-minutes of driving to figure out how to drive it smoothly, but a later s/w update, decreased it. In the process, they also ramped it up so it wasn't as abrupt. IMHO, not as flexible, but easier for the average ICE driver to drive it smoothly.

[bono]

530e has a better generative braking. My wife had earlier Mercedes B class full electric. You could choose the level of regen with the paddle shifters. There were 3 levels if I recall correctly. This was perfect - some people like one pedal driving, some do not.

[thewils]

Loving regen on the 45e myself...coming down some of the big passes here in British Columbia I can take my foot off the gas and don't have to ride the brakes all the way down. Brakes last longer, free electricity, what's not to like? There's a "different feel" to the brakes, but they work the same way. If you want to stop faster, push harder.

[jad03060]

As mentioned, the brakes in the PHEV are brake by wire...under normal conditions, it's entirely the computer blending regeneration and hydraulic braking to achieve your pedal selected stop rate. In this, I feel they did a really good job. You can get an idea of what is slowing the vehicle by watching the power meter. If you're slowing down and the meter is at zero, it's either friction/drag or the actual brakes...if it's showing regeneration, it's at least some regen.

[bono]

Can you figure out when the brake lights are on? The car is sometimes automatically braking harder if there is a stopped traffic in front. I was wondering whether this harder braking is regen only.

[biterror]

Originally Posted by bono

Can you figure out when the brake lights are on? The car is sometimes automatically braking harder if there is a stopped traffic in front. I was wondering whether this harder braking is regen only.

At least on 45e, you can see that on the "power meter" (whether regen is at max (which means real brakes may be used) or not).

[jad03060]

I haven't looked, but someone did say that at some deceleration rate, the computer will light the brake lamps on its own without you pressing on the pedal. With the right display up, you can see that. I know when I had my i3, the computer would light the brake lamps under those conditions, and I think I've noticed that in reflections on my PHEV, but am not certain.

[TexAg91]

Originally Posted by azim1223

I test drove my friend's tesla and when you're driving fast on the interstate and sometimes just let it coast it weighs you down immediately, I just find it unpleasant but from what you guys are saying, it's not as strong, which is better for me 😁

On a Telsa, you can set the software to coast if you don't want to "one peddle drive" -- it does take some getting use to. In coast mode a Teska won't regen when you lift off the accelerator (it will coast), and it will only regen when you depress the brake peddle (it will also use the mechanical disk brakes if you have to brake harder than what is provided by max regen).