The 05 636 wont be a good stunt bike for a couple reasons. Slipper clutch will limit engine braking. Not the biggest deal but a little. The biggest thing for serious stunting though is the swingarm setup, as it is you wont be able to go any higher than maybe 5+ on the rear sprocket or it will rub. Yeah all that can be changed but some of the new bikes are getting to the point where you have to change too much to make them good stunt bikes. Just my . But as far as the others go I have to say my 636 is great and for all the bikes I have ridden I think the only other bike I like almost as much as my 636 is an f4i.

 

I of course am going to say the 636 b/c that's what I use. But, whatever you do don't go with the new 05. There is power there but the gears are taller so you would have to go even higher with the sprockets. My 03 pulled harder w/ stock sprockets than the 05 does and it has a 43 on the rear instead of the 40 mine came with. The 636 is a great balancing bike but I chose to put MX bars on mine b/c stock bars make you lean too far over. I took all my plastics off and I think they make great looking streetfighters. I went -1 up front and +3 on back and can clutch it up in fourth gear sitting down. If you are going to use it for nothing but stunting I recommend you go -1 up front and +7 to +10 on the rear. You don't have to turn the 636 as hard as the R6 to make power either. If you have any specific questions about the 636 feel free to ask. I love talking about them almost as much as I love riding them.

 

The 03+ r6's have weak *** subframes.

 

636 ... that bike is it.