Forks fluid

[sthedreem]

I have a 1999 R6, I need to change my forks fluid.  I am looking for the fluid weight and fill level.  I use the bike for racing so I would need race setup info, not the stock street.
Thanks

[Thingy]

If the forks are stock, your service manual or a nice dealer should be able to give you that information if nobody does here.  

If they are Race-Teched, you can get that information on their website.  (I am not sure if the level is the same as stock.)

If they are Traxxioned, have Traxion do it.

[sthedreem]

The forks have not been redone (racing on a budget), I am only changing the fluid, but I wanted to find out the best fluid weight and fill level, considering that the stock fluid and fill level are ideal for the street and might not be suitable for the track.  If anyone has any reliable input please share it.
Thanks

[EX#996]

Suspension is a delicate science.....

I don't think anyone here can really answer your question because there are too many variables.  For example, Paul looks at the following before changing his fork fluid or level.

His weight
The temperature it is expected to be
The track
(There's another one that I can't remember, I think)

My suggestion would be is to talk with your dealer since your forks are stock.  A heavier fluid and level can make a difference and your dealer may have some idea as to the differences you may experience.

Good Luck!

Dawn   :)

[sthedreem]

I weigh 165 lbs, and ride florida and SE tracks ( for Temperature and track refrence), Savannah, Jennings, Atlanta, Daytona, Barber (soon).  
The stock level is 107 mm, the spec weight according to dealer is 5 weight.  I hope I have given some info to help.
Should I go with more oil (higher fill level)? or heavier weight fluid ? or both?
Thanks

[bweber]

If you reduce the air gap (higher fork oil level) it will give you a firmer feel progressively as your forks compress.  Changing to a 7.5 wt oil would give you more rebound and compression damping across the entire range of motion.  If you are an aggressive racer and prefer a stiffer front feel, reduce the air gap by 5mm (to 102mm) and try a 7.5 wt oil (or maybe new 5wt).  Reducing the air gap should really help, but going from 5w to 7.5 wt may be too much of a change.  I have heard of people mixing fork oil to get a different viscosity (like 3 parts 5wt to 1 part 7.5 wt) but I have never tried that or endorse that tactic.
Since you weigh in the magic 160-170 pound range that seems to be the weight to which most Japanese manufactures spring their bike, you should be able to get the proper sag measurements you need with the stock spring.   If you can get the correct front end sag numbers (about 30-35mm and 20mm free sag), you will be in the ballpark.
Be advised, the early R6's had Kayaba forks.  The cartridge has an orifice-controlled rebound mechanism that is non-rebuildable and simply doesn't work. The rebound needle has no taper and acts more like an on-off switch. You never will get a "good" setup without sending them out to be revalved by a reputable shop.

[sthedreem]

I think I am getting a little better understanding of how the oil level, oil weight and spring rate effect the behavior of the bike.  Thanks to all of you for your input.
The dampening of the forks is OK so therefore I probably should stay with the same weight.
The sag is at the maximum setting. Will having more fluid/ less air in the forks give me more room for sag adjustment and improve the compression ability and rate of the forks?
MY R6 is 1999 model so the forks are probably those being referred to (Kayaba?)  As long as the dampening is OK I shouldn't have to worry about that, right?
Thanks

[MELK-MAN]

I think I am getting a little better understanding of how the oil level, oil weight and spring rate effect the behavior of the bike.  Thanks to all of you for your input.
The dampening of the forks is OK so therefore I probably should stay with the same weight.
The sag is at the maximum setting. Will having more fluid/ less air in the forks give me more room for sag adjustment and improve the compression ability and rate of the forks?
MY R6 is 1999 model so the forks are probably those being referred to (Kayaba?)  As long as the dampening is OK I shouldn't have to worry about that, right?
Thanks

i would send them to Traxxion dynamics. if you dont need springs you would be looking at a few hundred bucks but the forks would be set up perfect for your bike, your weight and ridingstyle. you would get a spec sheet that you could then do the forks yourself by in the future.
what do you mean you have the sag at the maximum setting? sag is a measurement of how far the bike drops from fully extended to compressed with you and gear on the bike. to measure properly you must measure 2 things after you measure the forks fully extended....1) measure after pushing down on the bars a few times and let settle. 2) then meaure after pulling up and letting settle.  Why? because forks have what is called "stiction".. you will see a 5-10mm dif in these measurements. ADD them up..and divide by 2. this is what you then subtract from your EXTENDED measurment to get total rider sag. should be 20-25mm i think or so for racing. YOur preload adjusters at the top of the forks will let you adjust this.

[unforgivenracing]

stick to the manual on fluid changing.  It only a pain when you try to put the fork back together again.  syn types of fluid seem to be used alot.  [They don't heat up as fast or something] I know it makes for a long clean-up after a crash.

The forks have not been redone (racing on a budget), I am only changing the fluid, but I wanted to find out the best fluid weight and fill level, considering that the stock fluid and fill level are ideal for the street and might not be suitable for the track.  If anyone has any reliable input please share it.
Thanks