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n2shotokai

My Budget Suspension

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n2shotokai
Reading through all the different options on suspension I found very confusing and well, just downright expensive.
All my decisions were based on the fact I ride street and I am not doing track, so the emphasis was a decent suspension without breaking the bank.
On the rear it seemed entry level was about $650 and went over $2,000. That made it pretty easy, I went with the Ohlins because everything from Sweden is better ...................
I debated for quit some time on the front. My decision boiled down to the fact that several suspension people told be 80-90% lies in the springs being appropriate for your weight. That and a fellow board member replace the springs and was very pleased with the results. After seeing him ride I realized I will probably never ride at his level and if it was good enough for him.......  Any additional hardware beyond springs exponentially increased the cost. Therefore I opted for Race-Tech springs and 15w oil. Springs run $130-150, oil is cheap and you can make a major impact to the front end for about $300 with labor.
Yesterday I went for a 150 mile ride, mixed highway and mountain roads. The bike was much more stable in all conditions. Brake dive was almost eliminated. Cornering was precise and confidence inspiring. I am very pleased with the setup and the fact I did it all for much less than I first considered.
If you are considering an upgrade and wrestle with the cost I highly recommend just replacing the front springs and oil and go from there.
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pattonme
If you really want to pinch pennies, source springs from Sonic ~$85. They are perfectly good springs, just not paying for name recognition.
 
In any event, good that you found a cost-effective solution that you're happy with. Motorcycle-Superstore tends to have a decent selection of the heavier fork oils.
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pattonme
I added a lot of verbiage to http://fz07.org/post/25375 to help clarify the options available.
 
Moderators, is there a way you can update the "edited" timestamp on the linked post to reflect the updates?

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hippiebikerchick
I bumped it for you.  :)

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grahamfz07
Thanks for sharing your upgrade. Im thinking about your spring/shock upgrade on mine. I talked to a local suspension shop here and for the ak20 kit and ohlins shock it would be $2500 cad installed. Cant justify that for my style of street riding, let alone try and come up with that cash

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rowdy
I'm thinking of doing a Sonic Springs upgrade, and a Matris rear shock (so ~ $700 total). I put Sonic Springs on my last bike (Ninja 500) and it made a world of difference.

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fflier9
Can someone clarify this quick? I'm trying to firm up the front suspension, so I'm going to get some Sonic springs and fork cap w/ adjustable preload.
I looked at a graph and for my weight (200lbs) the spring rate should be somewhere in the .9kg/mm range, whatever.
But I have a shop manual here and it says the stock springs are already .87kg/mm. Wtf?

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pattonme
Yeah that .87kg/mm seems to be a bone of contention. First that would be a profound deviation from the Jap4 SOP. Second, the front-end dive that is observed is incongruent with the spec. I'll measure here shortly and provide an update.

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fflier9
Alright, thanks. I am curious. Also, I decided to read RaceTech's "motorcycle suspension bible" (it's up on...a certain torrent tracker...as a .pdf) before I decide to do anything and the author says that front end dive under braking is "totally normal". I've seen tons of posts about redone front forks where there is "no more braking dive". I'm sure this is highly suggestive but...what do ya'll think?

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n2shotokai
Alright, thanks. I am curious. Also, I decided to read RaceTech's "motorcycle suspension bible" (it's up on...a certain torrent tracker...as a .pdf) before I decide to do anything and the author says that front end dive under braking is "totally normal". I've seen tons of posts about redone front forks where there is "no more braking dive". I'm sure this is highly suggestive but...what do ya'll think?
For clarity, my posts should have said "no more excessive braking dive". Every bike have ever owned has some brake dive. But the FZ-07 was by far the worst. I think those stock springs are for a 120 pound rider. 

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so1102
Yeah that .87kg/mm seems to be a bone of contention. First that would be a profound deviation from the Jap4 SOP. Second, the front-end dive that is observed is incongruent with the spec. I'll measure here shortly and provide an update.
Be interested to see what you find out.  FTR the US service manual also says 0.87kgf/mm

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bmwpowere36m3
OP what spring rate did you go with and what's your approximate weight geared up?
 
Springs will definitely help with brake dive, but low-speed compression needs to be increased really. Changing out to 15w fork oil definitly helps that as the factory weight is 10w.

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pattonme
@bmwpowere36m3, oil weight does ~nothing WRT to the slow (but really also fast) compression circuit since the chamber under the rod "piston" is basically unrestricted. Ok, maybe if you ran 50W vs 10w you might notice.

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n2shotokai
OP what spring rate did you go with and what's your approximate weight geared up? 
Springs will definitely help with brake dive, but low-speed compression needs to be increased really. Changing out to 15w fork oil definitly helps that as the factory weight is 10w.
I was shooting for 250 pounds so on the front I went with .95. 

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bmwpowere36m3
@bmwpowere36m3, oil weight does ~nothing WRT to the slow (but really also fast) compression circuit since the chamber under the rod "piston" is basically unrestricted. Ok, maybe if you ran 50W vs 10w you might notice.
 
 
Your right, in that damper rod forks the damping is a function of suspension velocity and it increases with speed squared (exponentially). That's the downside of damper rod forks, to get sufficient low speed, you end up with way too much high speed damping.
 
*edit* are you saying the factory forks, have such large holes in the damper rod to provide very little damping?

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