[StanDiego]

Originally Posted by MisanoblueZ4

And I’m probably being overly careful but rather not subject the top mechanism to wind buffetting or road imperfections during its operation.

Not to mention 6+ years of owning a NC Miata PRHT that ONLY worked when at a complete stop is ingrained in my muscle memory 😆

I used a SmartTop module in my PRHT. Thankfully, I didn't experience issues with it such as in the attached service bulletin.
Power Hardtop Will Not Open.pdf
I'm sure the Z4's motor and mechanical parts are more robust than the Miata's and designed to handle the added stress of operating while moving. However, I can understand your concern. I never operate mine above 20 MPH, a number I arbitrarily chose as a compromise.

[Westside Guy]

Originally Posted by BlankProc

To each their own! Being overly careful in my opinion for probably one of the most convenient functions of the car.

On my previous convertible, a MB E450, I used it all the way up to the 37mph limit. Zero issues, traded it in at 22k miles.

Same so far on the new Z4, and tested over driveway dips, on windy days, up to 30mph, etc. No problems.

I have also done it without any issues between 25 - 30 mph. I love seeing the expressions on the drivers that are alongside me when I do it.

[bacampbe]

I've done it a few times. My last 3 cars were M235 or M240 verts, and they had a manual handbrake and put the top switch in the middle, which is in between where the brake and top switches are in the Z4. Both are within the range of muscle memory.

All but one were trying to lower the top when stopped. Nothing exciting, I just wondered why it was asking me to put my foot on the brake to lower the roof. I've done it once in motion, and that _was_ surprising, but not a big deal. At the sort of speeds you should be raising your top, you will feel a lurch as the rear brakes engage and let go really fast. Hopefully, you won't be trying to raise your top during a hard maneuver.

At the PDC, the instructor had us pull the e-brake at higher speeds. You could certainly feel it, but as long as you let go fast, everything should be fine. Hopefully you won't try to raise your top during a high-speed maneuver.

[MisanoblueZ4]

So of course this would occur today, while pulling into my neighborhood and moving I went for the “no look pass” top button and snagged the parking brake! I was only going 10-15mph so it engaged and disengaged quickly. No harm, just felt like I tapped the brakes.

[bacampbe]

Originally Posted by MisanoblueZ4

So of course this would occur today, while pulling into my neighborhood and moving I went for the “no look pass” top button and snagged the parking brake! I was only going 10-15mph so it engaged and disengaged quickly. No harm, just felt like I tapped the brakes.

From your experience and mine, it seems like the e-brake does not lock into the "on" position if you pull it while in motion. It's more like pulling a hand brake while holding the button down. It's like they designed it to be used for hand-brake maneuvers :-)

[MisanoblueZ4]

Originally Posted by bacampbe

From your experience and mine, it seems like the e-brake does not lock into the "on" position if you pull it while in motion. It's more like pulling a hand brake while holding the button down. It's like they designed it to be used for hand-brake maneuvers :-)

Agree because once in the garage I pulled the e brake switch it locked and stayed that way. I think as you do it will not lock in motion.

Just funny cause we were discussing using the top while in motion and I usually do not, due to forum peer pressure I went for a close before getting home and screw up ensued lol