What are the advantages/ disadvantages to jumping with a two line setup instead of a four. I have a two line 5m, and would like to know if there any dangers that are inherant to two line set ups.
Cavern

I may not have this exactly correct, but it is my two cents worth of knowledge.

Duo line and quad line are pretty much the same when it comes to basic flight. The difference is the second set of lines (brakes) allows you to keep the kite in a particular holding pattern. One can stop the kite and keep it in any part of the window. Duo line control never rest; accept at the zenith. That said, if all your interested in is jumping than holding a kite in place would serve no purpose. Both systems being equal, you can jump as high; leap as far, with either. I believe one has more choices in the size of kites when one uses quad. There are large duo controlled kites but I believe there are bigger quad controlled. More kite, more everything, including trips to the hospital, so be careful; wear safety gear.

One big factor is safety, if you come down hard with a 4-line and are using either KS-P-A-M-L-I-N-K-s or some sort of safety system on it, you can drop the controls and deal with yourself without needing to chase after the kite or if your left unable to, don't have to fear about the kite causing problems for others.

Now are you talking about swapping a 4 line kite over to 2 line, or is the kite originally made as a 2 line. Reason I ask is I haven't seen many new largish kites that are only 2 line. If you're using an older 2 line, be sure to check for wear, lines, bridal, sail, you don't want to be 10ft up and have something fail. should do this with any new gear as well if your pushing the limits.

Using a two lined kite jumping would be dangerous. If a sudden gust came as taking off and you could tell you was going to over the limits you just hit the brakes.

how big of a kite would i need to be able to do this? and also about how much would this cost me second hand? and should i get a two line or a four line?

oops i forgot the link
http://www.youtube.com/watch?v=TuetDfQ-1nY

The video you refer to is NOT power kiting it IS SPEEDFLYING. More in common with paragliding than kites.

No logical person starts out with a kite so big they get the major air you are seeing. You need to ask "what size kite should I get to learn to fly" and the answer to that is a 3 or 4 m.
If you want to do what you see in your film, take a paragliding lesson. If you want to kite, TAKE A LESSON !!!!!

Sorry if that bursts your bubble but it's the reality of what you see.

The crazy person with the paragliding link posted is me a long time ago and i am now into kiting and I will be getting into paragliding soon. YAY best of both worlds!

In my water skiing world this is the equivalent to someone asking "how do I make the ski spray water like that?" The spray is the result of learning basics and elevating your skills. The spray is the result of the groundwork and not to be the actual goal. The catch is that if you make the spray your immediate goal, you can't achieve it. Work up the ladder on skills and the spray just happens but you then realize that it was incidental to you doing everything else right.

The same scenario in kiting is more ominous because somebody probably gets hurt or tears something up.

All the jump distance records are done with 2 line kites - as far as im aware.

Apart from Erik Eck, but thats not really an official record, lol.

my first (pitifull) jumps; 2 line (i need handles)

But its a cool pic though

Should i get handles for jumping (most videos of pendulum use those soft handles)

i use handles cause they're a lot better for careful control and exact positioning. Its a lot free-er.

Its up to you if you use it though man, it doesnt make that much different at the end of the day!!!

Yeah I'm going to sell my 3 meter and use the cash towards a used pansh 8 meter ace. (in the 4 sale section) the 8 meter has handles so that should work out well.

Yeah, that'll do the trick!

I was messing around with my 6.4 blade the other day. I flew it on two lines! Pretty much off the hook. the wind was only 10-12 mph anymore than that would have been to much imo. One advantage I had was longer lines which gave me a bigger window Thats a plus to me flying static. But imo kites that big need to be flown on four lines to be safe. If you get out in big wind you can get carried away or lose your kite. With four lines you can use your brakes and saftey system. I am not saying dont do it because it is different and fun.just be careful.