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Just a guy with an SV1K
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Picked up my Redline 5wt synthetic fork oil just the other day :) A far superior and easier to find product.
 

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Oil? More like green slime!

I have an 03 S, silver, if that matters. Was time to change fork oil as I am second owner and have no info on whether it was done before or not. It was a low millage bike so I'm assuming not. So, I do the necessary research, gather the proper tools (I laid out $120 for a low capacity torque wrench) hoist up the front of the bike from the rafters with some of my arborist supplies and remove the forks. I didn't do my research very well because I did not loosen the caps on the bike. With the help of some latex gloves I was able to unscrew the caps. I turned over the fork and this weird mix of watery, globby greenish ooze poured out. It had blackish sediment in it and seemed to have separated into its individual components. I then used the brake cleaner and really pumped the crap out of the cartridge. Satisfied, I then used a hair dryer to speed the evaporation of the brake cleaner. Now this next part took entirely too much time. I measure out 494 mL of 5w Honda fluid and dump it in the tube. Just like the manual says it fills to the bottom of the nut on the inner rod. I pump both inner tube and inner rod many times to bleed air. Then I measure the air gap. 120 mm. Why? I dumped out the oil, 500 mL. Checked everything twice. I deliberated for quite some time on what to do and decided that measured air gap was more important than added volume and went with 150 mL gap. It's been too shitty out to reinstall and test, but the both hands on top of the fork leg and push test shows smooth movement and effective adjustment on damping controls.
The question is this. Why state exactly to fill with 494 mL? Then have to pull 30mL or so out to get the right measurement. Why overfill by 50 mm? Why not fill with 500mL? Is this similar to other's experience? I also did the steering damper. The same green gloppy shit came out of that. I also picked up an 05 GSXR 1K shock, but haven't installed yet.
 

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I love my SV
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5,783 Posts
I just recently done my forks cos I had to change a leaky fork seal.. I have had a Maxton fork conversion... But I put in 450ml of 7.5 Putoline fork oil in with a 150mm air gap... Haven't tried yet but hopefully will later if it's not raining and will report back...
 

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Thanks for the help and I'm still trying to find the OEM oil. There's just too many people on too many lists saying too many different things. Some say it's 2.5, some 5.0 and I've even read claims on other lists that its 10.0. I just want to use the same stuff that was in there originally. I had the suspension set up perfectly before and it'll be a lot easier to do again if everything is kept the same.
 

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Thanks for the help and I'm still trying to find the OEM oil. There's just too many people on too many lists saying too many different things. Some say it's 2.5, some 5.0 and I've even read claims on other lists that its 10.0. I just want to use the same stuff that was in there originally. I had the suspension set up perfectly before and it'll be a lot easier to do again if everything is kept the same.
Here you go. This chart from Motul will explain everything to you. The LO1 is between 2.5 and 5W.

http://www.motul.com.au/product_line_up/fork_brake_others/images/PDF/FORKOIL_EXPERT_BLEND_CHART.pdf

So using 5W is the way I went and if anything it could still use a slightly heavier grade.
 

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Crazy Old Foole
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7,313 Posts
and if anything it could still use a slightly heavier grade.
Any heavier, and your damping adjustment capability goes away.

Just think about trying to meter something through a syringe.
Which will be easier to quickly and accurately to move through it, chcken soup or cold molassass?
 

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A square wheel rollin' !!
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Thanks for the confirmation of the .85 springs, Longhair. By the way, I see that you also have a naked, silver model. There is no better measure of a man's intelligence than that he agrees with me!Ralph

Ralph, I loved that line. I had to steal it and put it in my signature ! Hope you don't mind.

Good info here on the forks , thanks again.

Mine have 10wt installed by the PO, so perhaps I'll swap it out for some 7.5WT Motul or Redline .

I read where some of you guys have used brake cleaner to wash out the forks internals. Is this ok , or can it damage the shims or other internals ? I used brake cleaner to clean the forks on my old Ninja , which worked great. Unfortunately, it developed a SERIOUS seal leak a few months after and has made me second guess using the brake cleaner. It only leaks on one leg though, so I suppose it was something else that caused the leak.

Anyway, what should I use to wash the innards ?





.....................Blake
 

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"Kiss my Ass"
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13,712 Posts
Any heavier, and your damping adjustment capability goes away.

Just think about trying to meter something through a syringe.
Which will be easier to quickly and accurately to move through it, chcken soup or cold molassass?
You've not seen my wifes chicken soup!!:shocking:
 

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KNEE DRAGGER
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5,122 Posts
Here you go. This chart from Motul will explain everything to you. The LO1 is between 2.5 and 5W.

http://www.motul.com.au/product_line_up/fork_brake_others/images/PDF/FORKOIL_EXPERT_BLEND_CHART.pdf

So using 5W is the way I went and if anything it could still use a slightly heavier grade.
Setting up any suspension these days you cannot do by "weight." Everybody's oils are different and in some cases some manufactures 5 wt is anothers 10wt. You need to decide on a cSt value and a hi VI fluid. What does this mean? It means a real engineering value for flow rates at 40C and 100C and a high VI value means it will changes flow characteristics much less when hot and cold than a low VI fluid. Modern forks really need hi VI fluids so they work the same on a cold day, and in race conditions on a hot day too. L01 is listed in my info as 15.5 cSt @40C. this oil might work well for some in stock forks but if you have stiffer fork spings you will not have a enough rebound adjustment to get them in the range they should be. Two ways to deal with this are a heavier oil or a revalve. Revalving is the best though. Heavier oil can helps but can also have adverse effects. Ultimately you want to use a light oil, as this will help the fork use the valving to control oil flow and not the oil it self. But this does take new valving and often new needle valves to control the suspension correctly.

Tuning can be accomplished by mixing oils as someone has mentioned and posted a link to it. This is great for the Motul oils but can not be carried over to other brands. Mixing of fluids is more complicated than what most people think. 50% 5wt and 50% 10wt by volume does not make 7.5wt. Resulting viscosity are dependant on the VBN (Viscosity blend Numbers) and then the mass fraction numbers need to be used to get the resulting viscosity. I just graphed up a blend chart for some redline 5wt and redline 10wt to show resulting viscosities are not the average of the two. The red line in the graph shows the result that most people would think you get by using a weighted average and the blue line is the actual resulting viscosity of the blend. They vary quite a bit.

For those that want to know

VBN = 14.534[ln(ln(v+0.8))] + 10.975 where v is viscosity in cSt
VBN blend = [Xa(VBNa)] + [Xb(VBNb)] + ... + [Xn(VBNn)] Where Xa and so on are mass fractions of the fluid in the blend
Now the resulting viscosity can be calculated by
Vr = exp{exp[(VBNblend - 10.975)/14.534]} - 0.8

I have also included a quick write up on the topic.

-MS
 

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