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Discussion Starter #1
After reading this http://www.motorcycle.com/manufacturer/kawasaki/2009-kawasaki-zx6r-review-first-ride-87491.html and this http://www.motorcycle-usa.com/157/1551/Motorcycle-Article/2009-Kawasaki-ZX-6R-First-Ride.aspx i'm really conflicted. I was leaning towards replacing the zixxer with the gixxer 750 but theres just something about this 09 that has me really, really excited.

I know i'll go faster on the track right away with the Suzuki but in the long run i'm pretty sure the zx will make me the better rider. Is it spring yet??
 

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Discussion Starter #3
Vash, what do you find MORE interesting the 09 ZX fork or the 09 R1 fork?

Back on topic...turn in speed has always been one of my weak points at the track. I wonder if this BP fork will give me the confidence I need in the front to get off the binders a little sooner...
 

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what exactly is a 'Big-Piston' fork? :confused: :dunno:
 

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Ryan:
can you send a link for the R1 fork? I haven't seen anything about it.

Ochoa:
At first glance, here is what I see.
Your typical upside down fork has two tubes (inner and outer) in the inside of the tubes, you got something that looks a whole lot like a bicycle pump. With the cylinder pointing down, and the rod pointing up. The fork spring is wrapped around the pump rod, toward the top of the fork.
The pump cycles oil thru valves, which regulates the speed it moves. All the extra tubes reduce the maximum diameter of this pump. Typical units are 20mm, ohlins sells 25 and 30mm units. Smaller pump diameters means that oil must flow thru smaller holes (also traxxion drills huge ones) which means that oil must pick up speed to flow. sort of a turbo lag-like effect.

This BPF design did away with the extra pump, and used the body of the inside tube for that. So they got rid of the little cylinder (which is very light), but now they are forced to place the springs on the bottom, near the unsprung end. I'm not sure why this fork would dive any less on the brakes, maybe I'm missing something.

I'll read on it some more, right now it just seems more expensive
 

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Discussion Starter #6
Ryan:
can you send a link for the R1 fork? I haven't seen anything about it.

http://www.motorcycle.com/manufacturer/yamaha/2009-yamaha-r1-unveiled-86809.html

The 43mm inverted fork is by Yamaha subsidiary Soqi, and it’s notable for having separate circuits for rebound and compression damping in each fork leg, said to be like the M1 GP bike. The Soqi shock has provisions for high- and low-speed compression damping, rebound damping, and in a nice surprise, a hydraulic preload adjuster.
 

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i dont know what you just said.... sorry, if i dont know how a regular fork works, there is no way i can figure a fathom on another type.... :huh:

i personally dont like how the 6R shares the same looks as the 10R, its nice to see that they responded well and scrapped the old 6R quickly shooting up a new design so fast! almost too fast....
 

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The 43mm inverted fork is by Yamaha subsidiary Soqi, and it’s notable for having separate circuits for rebound and compression damping in each fork leg, said to be like the M1 GP bike. The Soqi shock has provisions for high- and low-speed compression damping, rebound damping, and in a nice surprise, a hydraulic preload adjuster.
I must be unusually slow today. Every fork has separate circuits for compression and rebound, at least on a race rep. The separate adjustments for high speed is a nice addition, if it works, as I'm told that it didn't on the R6. The idea here basically works like this:
In a conventional upside down fork, oil is forced to flow thru one of two one way valves. One is for compression, the other is for rebound. Once thru the one way valve, it flows to a needle valve, which regulates it's speed. These are the valves you typically make your adjustments to (at the top and bottom of the fork). There is also a blow of valve, which opens up when an unusually large bump is hit. The blow of valve allows oil to bypass the needle valve, and go thru a separate, larger opening. This opening is not adjustable on most forks (but you can change it by replacing parts), however some forks have another set of large needle valve so that the bypass circuits can be throttled as well.
The next logical steps for improvement is to rig up an adjuster for when the bypass circuits open up (adjust the spring tension on those valves. You can do it now by changing spring washers, but you have to take the fork apart for that). One could go a step further and put an bypass valve on the bypass circuit, so there are 3 rates available for each direction of travel instead of two.

The hydraulic preload adjuster allow the manufacturer to move the preload handle to a remote location, for easy access. It is particularly useful on shocks, where adjusting preload is inconvenient. It could be useful on the Kawi BPF setup, where the spring are in an unconventional place. But all it does is moves the handle, it does not improve the fork performance in any way.
 

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Discussion Starter #9
From one of the first ride reports:
Up front there's a new big-piston Showa fork, which boasts fewer parts than a conventional cartridge fork, yet has three or four times the valve surface and works at a third of the pressure. The new fork arrests dive better than the previous equipment, providing less pitch and flatter ride motions. Mounted with a one-degree reduction in rake for quicker turn in, the fork is backed up by a "race-quality" Ohlins steering damper to maintain stability.
 

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Err, is that file available in higher resolution? I'm pretty sure my forks did not look like that.
 

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I'd been waiting to get into my Nov Cycle World which has some commentary on the 6R and it sounds great for track-only. Glad to see it comes with a stock damper. Now if they would only include the solo seat cover to complete that track bike orientation :rolleyes:
 

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That bike right there had me wondering if I was going to move to the '09 R1 or it for my next ride. I've wanted an R1 for awhile but I'm tempted to snag up a 600.
 

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That bike right there had me wondering if I was going to move to the '09 R1 or it for my next ride. I've wanted an R1 for awhile but I'm tempted to snag up a 600.
If you ride track, then the solution could be quite simple. Does the track you ride most often favor liters or 600's?

If you're not a track rider and do more long trips on it, I'd suspect the liter was a better choice.
 
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