Vehicles stop dead at sim boundaries, always, every time

The title says it all.. from the helpful people I spoke to, vehicles stopping when you cross a region boundary is common. I've only ever done it sucessfully once! 99% of the time, the Chopper Hoverboard (basically the first one I've picked up) stops dead, and I have to delete it, re-rez it to try again (which again, fails).
This is surely not good. Vehicles are hardely useful when used in just one sim!

Why does this happen? How can I fix it?

This is very commonly reported and has much to do with the technical issue that a sim edge crossing is really a fast de-rez/rez action and the poor sims just can't keep up.

In my very limited experience, Cubey Terra's vehicles fare better than some others (special Cubey sauce?) but even those get hung occassionally.

Well that's.. rubbish isn't it?
The sims are able to communicate with each other, I wouldn't even mind if there was a delay, but seriously, what's wrong with one sim transmitting object guid, position, velocity (or physics state), the other one waiting for all that then settings things in motion again when all the data is received?
I can only think that the bug is caused by unreliable packets being used to send the data, or packets being received out of order, either one of these combined with poor code in one little function could screw things up

But I mean come on, the front page shows vehicles..

I'm really alarmed at this, what's the typical success rate for crossing sim boundaries? As I say, for me it's worked once, out of about 20/30 tries.

The chopperboard is a really old vehicle, it always had some issues at the sim lines, but with all the scripting changes we have had since it was produced, Im not surprised it is even less reliable.

Most of the newer craft do pretty good at sim lines. With flying craft, the higher you are at crossing the better, I guess it is because you have less to draw as you pass through and it makes a smoother transition. This is a guess, I dont really know why thats true.

I have very few issues with any of my boats and sim lines, they all are fairly slow, so I dont know if that is a factor or not. As for flying, I almost never have an issue with my A11 Slipstream (Huns Valens) but Im spoiled, I rarely fly anything else because its a dream.

I took a ride on my Trent Cycle today, and crossed a dozen different sim boundaries with only one problem (my bike ended up buried in the ashphalt in the new sim, so I used the Edit tool to lift it about a meter).

Loki's right... A lot depends on the vehicle.

Yes, there are sim-crossing problems. And yes, it can be annoying at times. But I think your results are atypical, and can probably be addressed by getting a better vehicle.

- Ace

That would be due to a script I wrote.

If you have more then one script trying to control the object this will happen every time. Maybe this is why?

Well, after noticing a vehicle mentioned above (the A11 Slipstream II), I searched for Hans Valen, and bought one Im still experimenting, but it's already happened twice (I wasn't paying attention to a mini-map).
Cool vehicle, but hard to control! I have 1mbps broadband, a 3.2GHz HT CPU, 512MB and a very recent NVidia card (doom 3 @ 40fps)... yet if I were to press and hold a button until I saw the vehicle move then let go, it would turn to much I have to tap it, then wait and see what happens.
Is this normal?

Well, thumbs up, I bound F2 to "/phys on", a vehicle command which fixes un-physicsing done by sim crossing. Didn't need to use it! Flew (slowly + badly) around Oak Grove, then flew all the day to Da Boom! No problems! Then it crashed and sent a log Well, at least LL will know about the problem
Super!

Er... yes. Full credit to border-crossing-goodness in a Cubey Terra vehicle goes to a clever little add-on script by Apotheus.

Seriously tho, I've said this dozens of times: the sim border problem is the single biggest problem with SL. Even without a vehicle, crossing the border can be hazardous.

Hey, try this for fun. Try flying through coordinates (0,0) of any sim without a vehicle and see what happens.

Sounds to me like you've got a solid case of lag...

Naturally, but I'm not convinced of the cause. My ping ranges 150 - 190ms.. good/bad? I'm pretty sure its not graphics lag.

It should respond within a fraction of a second. If you are pressing an arrow key and it is not moving in less than a second, something is probably wrong. I would guess there is some issue between your machine and Linden Lab's data center. Run a traceroute to sim50.agni.lindenlab.com and see whether there is any network congestion.

Also, if you are running any sort of file sharing programs, uploading stuff to a FTP server, etc., it can cause quite a lot of control lag.

Now, if it is flying normally, and you cross into a new sim, and it does that "moving in a strange direction/not responding to control inputs" thing for five or ten seconds, that's a problem within the SL grid itself, and will not go away without some rearchitecting by LL.