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Chassis instability?

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truthiness
Okay, so I went for a 'sporty' ride today and noticed that after cornering, when bringing a cheek back up onto the seat, the bike is not happy about that weight shift and gave me some feedback in the form of lateral 'wiggling' - nothing super bad, but a bit unnerving nonetheless.  I installed the Ohlins shock a few days ago and have yet to get the Andreani cartridges put in; could the lack of balance between front and rear damping cause such instability?
 
Possibly related: the steering is highly sensitive to input, and feels lighter/more unstable than when the bike was purchased.
 
Edit: it may be mostly my lack of skill, but good to know if something else is up.  One of the lower fork legs was replaced a few months ago, and I don't entirely trust the place that did the work.

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thomascrown
Use your legs to lift your ass, then move it. If you drag it across the seat, it will upset the chassis.
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rick
The Ohlins shock in my kit had a bit too much preload dialed in. That raised up the back end a bit (my reach to the ground was noticeably longer) Raising the back or lowering the front will always quicken steering. With the low weight and short wheelbase, this bike already has very light steering, so you do have to be fairly smooth. But check your sag measurements - and ride height as you sit. It might just need some adjustment on your part to how differently this shock works (as opposed to how the OE one really didn't work)
 
Get the front done - if not by yourself, someone you Do trust. Nothing worse for one's own self-confidence than to be worrying about something falling off.
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gregjet
Rick, I had the same problem with my Nitron when I got it. WAY too much preload as sent. It is possible that you could have what I call "preload blues" . That's where the preload is way too high or rebound is too low. The rear suspension returns way too fast to extended position and the rear unweights or oscillates.
The bike is rear weight biased fairly heavily, so it also helps to move fairly far forward and weight the front mid corner and on the exit . I found that hen I first rode the bike when I tested. Almost have to ride it motard style to get enough front load . Many have found lower bars and/or replacing the canted back bar clamps with ordinary straight up ones helps keep the weight forward.

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rick
Never gave much thought to weight bias, but the super short wheelbase can't help that.
 
But I really did mean just a bit too much preload. The shock had 3 turns more than what's considered the start point. Removing 2 turns (and setting the rebound 2 clicks softer) allowed the shock to start working nicely under my whopping 135 lbs. My next ride will be with that 3rd turn removed.
 
Guess i should have a look at the spring that was installed. Can only guess it's either the lowest rate or darn near the lowest that Ohlns makes.
 
At 5'5", gettin forward on any bike has never been an issue. I go back and forth between an Aprilia Futura with bars raised 1/2" (did that for hand comfort as much as getting my soft bits off the tank, lol) . That bike would be perfect for me if the bars were another 1" further back/up and the pegs a bit lower. Pretty much flip that for the FZ - down and forward a touch for the bars and mostly just back for the pegs. I'll talk about it more likely than actually do it though.
 
1st things 1st - gotta get that cartridge kit in and massaged to my liking

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gregjet
I found when I first rode the MT that even with my 84kg (190lbs roughly) , I had to move right forward. Seriously, I am talking almost motard forward to give the front some bite. That is with the 50hp neutered Aussie LAMS model . I have pretty much fixed most of ti but still wants to run wide a little. Fix so far is Nitron shock, heavier spring, rear raised 25mm new (adjustable) linkage. Stiffer front springs, bar clamps replaced with non canted ones, Renthal low bars and ecu reflash to calm down he throttle. But wiggle is something different. Is it still doing it? Tyre pressures as well may be worth a check.
Or AXLE tightness. There was a report on this forum or maybe another I am on of the bike being delivered with the rear axle loose.
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truthiness
It hasn't really done it since posting about it. I am loosening back up in my riding a bit now - it took me a bit to calm down in the saddle after lowsiding it. The only time I can get it to wiggle like that now is if I induce it by pushing to and fro on the bars. It is still a bit unstable on rough pavement when cornering but that's to be expected, especially since I haven't done anything to the forks yet to balance with the Ohlins out back. I truly appreciate everyone's input - you guys rock.

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YZEtc
My Ohlins shock came out of the box with enough spring preload dialed-in to make the rear suspension "top-out" with the bike's weight on it.
That means even after I installed the shock and lowered the bike back onto the ground, the rear suspension was still fully extended due to the spring being cranked down so much, where it needs to compress 5 to 15mm under it's own weight (called "free sag") according to the Ohlins instruction booklet.
 
If I were you, I'd set the rear spring preload to achieve the recommended 25 to 35mm of rear suspension compression (called "rider sag") with you sitting on the seat.
I set my rider sag to 30mm and the bike handles like a dream for me, and I have the stock front fork, too.
Not a hint of instability, unless I do something dumb.
 
If the bike feels too twitchy, maybe the rear spring preload is too much, jacking the rear up too much, as mentioned above.
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gregjet
Stiff arms will do it...
What YZtc said. Twitchy and wobbly are different things though. Twitchy rear is probably the front of the bike, wobbly is probably the rear ( or riding too stiff).

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truthiness
So I know this is old, but I'm finally settled down in a place with a garage and got a chance to do some maintenance on the fizzer. Lo and behold, the dealership that did the work on my bike after lowsiding did not align the rear wheel correctly :^( I aligned it myself and now she rides like the day I bought her!

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rowdy
So I know this is old, but I'm finally settled down in a place with a garage and got a chance to do some maintenance on the fizzer. Lo and behold, the dealership that did the work on my bike after lowsiding did not align the rear wheel correctly :^( I aligned it myself and now she rides like the day I bought her!
Yea, the whole "wiggly", and "unstable" thing is a complicated equation that I have yet to see a formula for.  It involves so many variables, some of which are the bike, i.e. wheelbase, fork angle, trail, alignment, wheel/tire balance and trueness, headset bearings, stiffness, then throw in the rider... rider weight, where the rider likes to sit, how the rider changes position in turns, then throw in the road you are riding, washboard, rippling asphalt....  I'm glad you figured it out, cause it can be hard to solve.  The FZ-07 is a light, quick handling, short wheelbase machine that is more susceptible to instability than some bikes.  That said, I've never had a problem with mine (crosses fingers), but I can tell when I intentionally induce some instability, it doesn't immediately stabilize like some of the bikes I've owned. 
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