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Discussion Starter · #1 ·
Does anyone know the volume of oil in the front forks on an 03 999? and what Weight to use?
 

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DanTheMan said:
Does anyone know the volume of oil in the front forks on an 03 999? and what Weight to use?
That really depends on your weight and riding preference...

OEM the 999 comes with ~475ml of 7.5 wt fluid.

I'm 165 w/ full gear and I'm going with .90kg springs 120mm 5wt fluid as recommended my Jason @ Section8Superbike I'm still waiting on my springs to get in, but 5wt fluid is too light for the OE 1.0kg springs; you lose almost all rebound damping. Keep in mind that spring rate, oil weight (and level, to a degree) and valving all work together to affect fork action.
 

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Discussion Starter · #3 ·
Bella749 said:
That really depends on your weight and riding preference...

OEM the 999 comes with ~475ml of 7.5 wt fluid.

I'm 165 w/ full gear and I'm going with .90kg springs 120mm 5wt fluid as recommended my Jason @ Section8Superbike I'm still waiting on my springs to get in, but 5wt fluid is too light for the OE 1.0kg springs; you lose almost all rebound damping. Keep in mind that spring rate, oil weight (and level, to a degree) and valving all work together to affect fork action.
Thanks, ultimatly i will get it revalved and resprung for my weight once i get some cash to do it. In the mean time i just wanted to refresh what was in there myself. I think the forks have been siting a while.

What brand of springs are you going with Race Tech?
 

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I ordered race-tech b/c I got 'em cheap on eBay ($93 new from M.A.W.)

If you wanna go the cheap, easy, DIY route that is what I'm doing. If you are going for a full re-valve/setup check out Traxxion They are one of the best in the biz. Top dollar, but worth it IMO.

BTW- I think I overestimated on the Volume... start with about 425ml(cc) per leg and work up in 5ml increments. I got alot of late stroke harshness I'm attributing to too much fluid. I will be using the recommended 120mm air gap when I rebuild here shortly.
 

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What exactly are the effects of changing the weight or volume of the oil??? My wife's SS has too much (i.e. VERY SLOW) rebound. Everything else seems to suit her for now though.

P.S. Sorry if this qualifies as thread jacking!!
 

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Thinner oil will speed up the compression and rebound, all things being equal. Sounds like just what you are looking for to speed up the rebound. It will make for less compression as well, but on a streetbike, that's always welcome.

More oil will make for a smaller air gap at the end of the stroke (bottoming), which acts like a progressive spring, which kinda sucks. It will keep the fork from bottoming, but occasional bottoming is not a bad thing.
 

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Discussion Starter · #7 ·
galaxy said:
What exactly are the effects of changing the weight or volume of the oil??? My wife's SS has too much (i.e. VERY SLOW) rebound. Everything else seems to suit her for now though.

P.S. Sorry if this qualifies as thread jacking!!

I believe with lighter oil, thinner. Imagine swishing water through your mouth, then imagine trying it with oil. he thinner lighter weight will flow faster. the thicker heavier weight will flow slower.
 

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Yep, exactly. The 800SS has "damping rod" forks meaning the rebound and compression damping are controlled by a fixed orifice. You can experiment with different oil weights and levels to change the damping rates but rebound and compression will be affected similarly. You can get some degree of adjustability with a Race-Tech emulator (see Traxxion above) setup.
 
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