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Im at 160lbs and rear shock adjusted is ok for me but i want to change fork spring & oil to resolve diving on hard braking, anywone have only upgrade front suspension and how it work with rear stock shock?
 

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I did the Stoltec spring and 10wt oil in mine and I still have the stock rear shock, I really noticed a difference in the brake dive. I'm almost 190lbs without gear and I opted for the 0.90 kg/mm springs as recommended by Nick at Stoltec. I do get some bobbing caused by the rear shock and I'm planning to replace it before next spring with a Öhlins shock.
 

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Ideally, doing the front and rear at the same time would be best. An improvement in the front, may make the back feel worse. For myself, I'd replace the cartridges in the front, with new springs, and a Penske double clicker in the rear. The ohlins unit looks nice, but I'd get more personalized suspension rates with the Penske.
 

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I've got a good shock on the back and simply swapped to 10W oil in the front, to the factory level.
It improved things but not by a huge amount (30% - 40%) still dives and bounces back up but, I'm going to try 15W and maybe add another 20 - 50mils per fork and see what that does.
I weigh 154lbs.
 

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I would do the rear shock first. It will improve suspension more than the front IMO. Check out the zx10 shock threads if you go with the rear.
 

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I've got a good shock on the back and simply swapped to 10W oil in the front, to the factory level.
It improved things but not by a huge amount (30% - 40%) still dives and bounces back up but, I'm going to try 15W and maybe add another 20 - 50mils per fork and see what that does.
I weigh 154lbs.
If it bounces back up, your rebound may be too fast. Go harder on the rebound.
 

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Im same weight and i upgraded spring and 10w oil... I also had them slightly raise oil level from stock... Feels much better. I do have a zx10 rear shock in my posession that i have yet to install, but the forks feel much better than they did before... You wont notice a huge change when you're just riding, but under harder braking and cornering you will definitely notice the improvement.

08-2010 zx6rr (note the double r)
08-10 zx10 / zx10r if im not mistaken can be retrofitted by just increasing rear hole size from 10mm to 12mm
If you want to face canister down you wont need any other changes but if you want to face cannister up to keep away from engine heat you will need to trim the plastic tray beneath seat edge slightly.

Kaiser
 

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One turn with a flat blade screwdriver. Turn it all the way in clockwise and turn it 360 degrees counterclockwise which equals one turn.
 

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I've got a good shock on the back and simply swapped to 10W oil in the front, to the factory level.
It improved things but not by a huge amount (30% - 40%) still dives and bounces back up but, I'm going to try 15W and maybe add another 20 - 50mils per fork and see what that does.
I weigh 154lbs.

At 154lbs I would have thought 7.5w would have been thick enough. I wouldn't do 15w if I were you - if you make it too thick then your front end may chatter and bounce when you're braking.
 

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Im interested in what temperatures u guys ride in with oil changes (pls provide brand and weight)

, the VI (viscosity index) affects how big the fork's temperature sweet spot for damping . Mineral ones only cover up to +-6 degrees C, while all out race spec ester oils can up it to +- 10 degrees C imho.

eve more if you have a clicker~!

As i said, the weights have no standardization, brand X's 20W could be as thick as brand Y's 10W in 20 degrees C for example...

thats why I need a baseline (yamaha's oil OR a certain brands oil, like the maxima 10W mentioned )

For ex :

the maxima 10W which I presume to be the Maxima Racing Shock fluid , has 2[email protected] deg c and a whooping high VI of 336

I guess the oil yamaha added inside could be:

YAMAHA G5 which has 16 [email protected] and given it might be provideid by kabaya, a puny VI of tops 150

Yamaha aint gonna retool or buy oil just to make the FZ09 better, remember its bottom shelf pricing?

Now I could use some temperature data so i can pull a spreadsheet off~ :)


As for bottoming, its more related (i' say 60-70%) to the oil height (yamaha wont put more oil in! cost cutting hits like a brick wall again!!)

Peter Verdone Designs - Oil Height

If anyone can give me the initial stock oil height AND how many ML of fluid it takes to go up 1 or 5MM , that will be rad too, topping up with enough fluid will cause the air spring to come into effect faster and theoretically lessen the chances of bottoming.
 

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Spreadsheet really. Back when I was young they put cheap fish oil in the forks which cleared out the neighborhood when you drained the nasty crap.

I have tried everything from Racetech to Bel Ray, and the Maxima Racing Fork fluid passed my scientific research (a ride down the road).

From Maxima:
Zero Drag Formula – 5wt, 7wt, 10wt, 15wt

Maxima Racing Fork Fluid is designed to drastically reduce stiction and meet all front suspension needs on both standard & cartridge systems. This advanced formulation utilizes the latest friction reducers, anti-foam, rust & corrosion inhibitors and is resistant to oxidation & viscosity changes. This viscosity index over 190+ assures constant fork action over a wide temperature range and also contains seal conditioners and shear stable polymers for long life.
 

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The Yamaha stuff is Kayaba 01.

Stock oil height is 147mm on the left leg and 148mm on the right.

I currently have 5W Silkolene, a about 22Cst it's a little thicker than the stock stuff.
 

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As far as height is concerned, fill it up with the fork collapsed and level, pump the rod slowly until you get hydraulic resistance all the way up, let it down, insert the rod, and suck out the excess. I have an example of a homemade level tool in a suspension forum.
 
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