$8400 is a fantastic deal for an FZ8, I can see why it would be hard to hold off. The FZ-09 looked really great on paper and in picture and when I first heard about it, I had just bought a new 2012 FZ8 the week before, back in February this year. I was pretty ticked off about that, because for one I could have bought a 2013 version with adjustable suspension (sales guy did not mention this!), and then to hear how great the FZ-09 was supposed to be just got my goat, so to speak.
But then I really started to think this over and as usual there was a catch, as all of the above sounded too good to be true. I had thought to pick up an FZ-09 when they became available in September as it sounded like the perfect bike. However, as I learned more about the actual design and construction, I thought there had to be something not quite perfect about it. The price seemed much too low for a bike with the feature I needed. I learned first of all that the FZ-09 had a bolt-together frame, which gave me some concerns. Some folks in the motorcycle press called this "tuned-flex" and "trickle-down" technology from MotoGP but as I had ridden both the Honda SuperHawk 1000 (which Honda touted as having a so-called "tuned-flex" frame) at Las Vegas Motor Speedway and found it to be a poor track bike due to weaving and frame flex in high-speed turns, I was quite suspicious of this. I also rode the FZ6 when it first came out, which has a bolt-together frame similar to the FZ-09, and it too exhibited weaving and instability at higher speeds. (The SuperHawk I mentioned had a cast one-piece frame of very high quality, not a bolt-together).
The video reviews posted in the last few days have confirmed my concerns. Both MCN and Visor Down have stated that the front end feels vague and not completely trustworthy (I may be paraphrasing but that's the gist of it). Another concern I had was the "ride-by-wire" throttle control and here again, both reviews have stated that it is abrupt when in full-power (standard) mode making it hard to modulate the throttle from a closed position in slower turns and around town.
For me, coming off decades of sport riding, racing, and track days, those two items are the biggest priorities. If a bike feels vague when getting it deep into a turn, and then abrupt when picking up the throttle, it just spoils the fun if deep lean angles and smooth, fast cornering are your thing, and those things are definitely something I like to do under the right conditions.
To take it a step further, my current sporting rides are a 2012 FZ8 and a 2012 GSX-R 750. The FZ8 now has just under 5,000 miles on the clock and has proven to be a superb ride. It rails through the turns and is especially stable in higher-speed bends. It turns quickly, handles very well in traffic, and just doesn't do anything wrong. Since I got a 2012 I did replace the stock shock with the Ohlins base model for about 650 bucks US but I saved that much on the bike so it worked out.
Being as I have the GSX-R as a benchmark for handling I can state without any reservation that I would take the FZ8 out to the track in a hot second; in fact many track day instructors use the FZ8 for just this purpose.
It looks like the FZ-09 is very good at pulling wheelies, doing burnouts, and laying big streaks of black from the rear tire but I really don't think most of us buy a bike for those reasons. To get a bike with this kind of power and light weight for a newer rider is a pretty big leap and the abrupt response and vague front end will only compound the challenges. For someone with lots of experience those two things will also tend to sour the milk quite a bit.
I don't think that it will be a simple thing to correct the FZ-09's issues; an Ohlins and a fork oil change was all it took to put the FZ8 where I wanted it but I know the bike actually works pretty well even without these mods. But it starts off with a one-piece casting and a very rigid frame sourced from the FZ1. If the vagueness is related to frame flex then there isn't a whole lot that can be done; a tire change to Pirelli, which has a more compliant carcass than the Bridgestone, might help, as well as a very good setup for the particular rider. Bumping the rear preload, for example, could put a bit more weight on the front tire and damping adjustments or fork spring preload might help. But this all remains to be seen. The throttle response is also a tough one as one would need to purchase an electronic aftermarket module such as Bazzaz or Power Commander and experiment with various maps and dyno tuning, etc. Unfortunately these modules don't seem to cure abrupt throttle response as much as tune the engine for more power when fitting a pipe or air cleaner. I learned this through personal experience. So as the reviews say the bike is not perfect and I am just trying to expand on why I believe these problems exist and how they might be addressed.
I am not trying to talk anyone out of buying an FZ-09 because like any bike, it has its strengths and weaknesses and for some will be just the thing. But as the poster said, common sense tells one to sleep on it. I am no longer considering the FZ-09 as I bought the GSX-R 750 as my track day and sport bike and that was the right decision for me. I would just recommend waiting until the full reviews are out on the bike before pulling the trigger on one because the FZ8 is a known quantity, four cylinders, stable, reliable, and without either of the two issues that seem to come with the FZ-09 and thus it (or something similar) may be a better bike for some of us. There will likely be plenty of them out there after September at bargain prices brand new, and the FZ-09 will likely be fetching top dollar at first, so hanging tight for a while longer might not be a bad idea.