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Discussion Starter #1
Has anyone tried to set the sag on a stock 04 F4i ?

Double check my sag measurement technique:

With the help of a friend and my Pit-Bull Front stand, we tried to adjust the front fork sag to the recommended 30-35mm range. I weigh 150 lbs with no gear, so figure 160-165 with gear. Anyway, I put a plastic zip tie on one of the fork tubes, put the bike on the front stand (supported by the steering stem) and pushed the zip tie flush with the fork seal. We eased the bike off the stand, then I got on the bike in a typical tucked seating position while a friend held the bike upright. I then measured the distance between the fork seal wiper and the lower edge of the zip tie. We duplicated this several times as we adjusted the preload on the front forks.

Initial stock sag: Preload adjuster w/ 3 lines showing and the 4th even with the edge of the adjusting nut surface gave 44mm sag. From there we adjusted the preload until eventually we got to almost no preload adjustment remaining (<1 thread showing) and still had 40-41mm of sag.

Do these sag numbers seem correct?
Has anyone checked their sag and gotten similar numbers? I had read that the F4i had a soft suspension, but this is a bit extreme in my mind. I am no where close to recommended settings and will need new springs, etc to get the front forks anywhere close to what I will need for light track duty.

Any recommendations, opinions on what to do (get a 600RR or mod the F4i)? I plan to do 2-4 track days per year starting out, then maybe 5-6 later on. I have been looking at Race Tech springs ($110), new fork rebound gold valve ($160), fork oil ($25), other options? ; but all that adds up if I lack the tools to do the work myself.

Per the Racetech website using their spring rate tool:

Street Usage
Rider Weight: 150 lbs.
Recommended Spring Rate: 0.793 kg/mm (use closest available)
Stock Fork Spring Rate (measured): .660 kg/mm (stock)

If modding the susp seems the best route, I am thinking of the 0.90 rate springs. The rebound gold valve or gold valve kits are something I'm not quite sure about, are these really needed with the fork oil & spring rate changes?
 

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Sounds about right if the stock springs are 0.66, that's very soft. Your method seems fine. To me it seems kind of silly to go with much stiffer springs and expect the stock valving to work, but I can't tell you from experience. Another option is to pay a suspension shop to revalve your stock components, that way you don't buy the tools or the special RT valves, but you do pay for a pro to service your forks.
 

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Discussion Starter #3
After checking the online fiche at ronayers.com, I think that maybe Honda changed the spring rate on the 04's possibly. There's two different spring part numbers listed on the 99-05 fiche.
Hopefully I can confirm this somehow.
 

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Springs without valves...no worries there, Unless you are a VERY fast rider on the track...the springs alone will help immensely! Without setting sag, you will never know if your damping is adequete but my guess is with your weight, its probably just fine.

If you go with RT springs...go with the .85's. Thier spring weight estimator rates low. (I have used 3 different sets) Dont go up in oil wt, you will harshen up the damping. Use a good oil..(Maxima, silkolene etc,,) but stay with the stock oil Wt.
The valves will make a difference as well...and if you are gonna tear the forks apart, and you have the $$...get the gold valves as well. But...if you are on a budjet, the springs are definately the trick!
 
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