As to whether you have to buy longer cables depends on how much added height and pullback you are doing over the OEM. Find out the ht & pullback on both the OEM and the desired bars and compare. These charts can usually be found on the web and you dealer should have them too.
If you have to buy longer stuff, you can get easy wiring extensions from Namz. They come with matching male and female pin sockets to match you bikes OEM pins. You simply plug in the pins and slip over the supplied heat shrinks on each wire. The pins work great because they are not as bulky as crimps and less trouble than soldering.
Here's the link,
NAMZ . CUSTOM CYCLE PRODUCTS
There are several places that will make you up custom cable and brakeline lengths. This is one.
Magnum Shielding - Custom Harley Davidson Cables and Braided Brake Lines
There's a 2 part video of when I did my handlebar switch on this forum somewhere but I forgot where. If you have trouble finding it let me know and I will just go to YouTube and grab the link for you. But it shows just about everything you are gonna run into with it. I have another video also on the tank removal which is also gonna have to be done to access the frame wires conveniently.
Check around with Wild1s and some other bar makes. I personally would not pay $8xx bucks for new bars and parts. My total job doing it myself came to bout $225 and most of that was the bars themselves.
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Is you bike one of those newer ones that has the risers built into the top tree ? If so then you are up against a different set of circumstances and will have to spend more money but you still should be able to get by for much less than $800.
There are a couple of options to this problem also if that is your scenario let me know and I will search down some of those links.
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