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GP Suspension Re-valve Kit


koth442

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Has anyone done the revalve kit from GP suspension? The price is right and with some DIY might make a huge improvement. Especially with some fork springs.
 
 
http://www.gpsuspension.com/GP-Suspension-Fork-Re-Valve-Kit_p_20449.html
 
 
Matt has a link to here which includes fork springs... Hmm...
 
 
http://www.stoltecmoto.com/shop/yamaha/fz-09/14-fz-09-fj-09-xsr900-fork-piston-kit/

'15 FJ09

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That is a good price for a DIY upgrade, once you add the fork springs you are at $280 + S&H.
 
I am all for saving money and doing the work myself when I can, however there are certain projects I leave to the experts, like suspension modifications.
 
If you get a quote from @pattonme his price isn't that much different for a finished product, and you dont have to buy any specialty tools. I also believe Matts forks go above and beyond this kit, with rebound and compression valving/pistons in each fork leg, plus you can opt to have rebound caps on both legs.
 
Another point to consider is along with his experience in building forks is his knowledge after the purchase should you have questions. With the DIY kit you are on your own.
 
" Also, please be aware that installation instructions are not provided with this kit and technical support is not available for your installation. In short – we can’t see what you’re doing, so make sure you know what you’re in for or find a qualified local shop who can complete the installation for you."
 
If you have the correct tools and the knowledge to truly DIY, this sounds like a decent option for a fork upgrade.

***2015 Candy Red FJ-09***

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I've got the GP piston kit (along with new springs) and it's definitely a notable upgrade from the stock stuff.
 
Before changing out the internals, I seriously wondered whether I could keep the bike, as the front end response was harsh and skittish over bumps, making it hard to enjoy the ride.
I had sag set properly and tried numerous numerous experiments with rebound settings and fork oil, but nothing felt quite right.
 
I didn't install the GP kit, myself, but my local suspension guy who did called it "the best bag for the buck" in terms of upgrading suspension.
Having ridden nearly 20,000 kilometres on it since, I'd be inclined to agree.
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Has anyone done the revalve kit from GP suspension? The price is right and with some DIY might make a huge improvement.
It still only puts damping in the one leg which is a compromise. I've only seen a 2017 kit so can't comment on how GP/Nick did the compression valving on the earlier bikes. If you don't have an extra pair of hands or things like a spring compressor it makes things a little more challenging but still within the realm of DIY.
 
I'm not sure why the GP/Stoltec kit has a replacement needle. That step is a comparative bit*h to do. The new needle taper is very, very very similar to OE. The new needle is ~same as 14-16 needle. The '17 is much shorter and thinner and thus the replacements make perfect sense. In rebound, minute adjustments are not that important. What is more useful IMO is to drill out the 1.5mm bleed to 2mm in that same assembly. But if you don't have a lathe or soft-touch drill rig, you aren't pulling that off.
 
Anything short of a lead pipe is better than OE so I'm sure you'll be sufficiently impressed with the upgrade.
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Bear in mind these are for a 2017 FZ09 which uses a mid-valve for compression duty. The kit you're planning to buy uses a base valve for compression and is a lot easier with which to get a good damping curve. The thin and dotted orange lines are my ideal goal as achieved by doubling up the damping curves you can achieve if the compression damping was being done by the base valve as it is the world-over with 4-piston cartriges since the 90's.
 
As you can see, when you put the compression on the mid-valve is a tough business. And which is why the Andreani kits have such a "too harsh" review. Ditto the NIX-22 and similar ilk.
 
This is a progression of modifications.
 
2017 FZ09
 
17fz09_oe_MVc.png
 
Penske piston kit as delivered.
 
17fz09_stoltec_comp.png
 
Flip tube, remove faux base valve
 
 
17fz09_stoltec_comp_with_bleed.png
 
My piston but kit valving, otherwise same as previous
 
 
17fz09_fbm-stoltec_valving_mvc.png
 
Back to penske piston, bleed upped to 2.7x2 and major change to shim stack
 
 
17fz09_fbm-penske_4.4_bleed_best_MVc.png
 
Same as previous but preloaded 0.1mm - what I would like to do but "can't" unless I machine the Penske piston.
 
 
17fz09_fbm-penske_4.4_bleed_preload2_MVc.png
 
 
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What machining operations would you need to do on the Penske piston(s)?
 
Nice charts, I really like those. Can definately see the progression, and the different layers of damping. Low, mid, and high speed damping on the last one.

'15 FJ09

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I would have to dish the piston face at 0.67 degrees.
Also, please see my edits to post #6. The 2017 needle is indeed VERY different from the previous years and thus the replacement from GP/Stoltec is totally warranted. I was erroneously comparing needles against the 2014-16.
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I wish I was smart enough to understand any of that.
+1 
I understand the outside clicker settings, I'll leave the internals to the experts.
 

***2015 Candy Red FJ-09***

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