I don't own a Yuba, but I just read a review in this forum. You should check it out.

1.No: You may want to check out big apple tires. If you can't get them yet. I've used platic strips that go between the tire and innertube.

2. no clue

3. Get a good u lock (bulldog?) and a good cable lock. Use them both. Someone that wants to steal your bike will need two different types of tools to steal it.

4. I don't know, but the ones for the xtracycle might work. Hopefully someone else will chime in.

Welcome by the way.