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FZ-09 Fork Springs and Tech Specs

After nearly a month of the FZ being down and apart, opportunity came knocking today: 60 degree weather, sunshine, and a fully-functional bike. Didn’t even need to don the heated gear (sweet!).

First order of business…the forks. As mentioned earlier, I weigh about 178 lbs in the buff. Fully geared up (with street clothes underneath), I weigh in at about 204.5 lbs. I have three sets of springs earmarked for ‘spring rate development’ (0.85, 0.875, and 0.90 kg/mm). Based on what was learned about the stock springs and the valving, I decided to jump right to the 0.90 kg/mm. Rider sag is currently 40 mm with 1.5 bars of preload. Oil weight was increased to a 10 wt Motul to add additional damping. Due to the lack of a service manual, I took a stab at the oil height (currently set for 150 mm). Still have plenty of travel left, but admittedly, I only got about 30 miles in on smooth tarmac.

Long story short: the spring rate feels great, there is still remaining rebound adjustment (unlike the stock setup), and the high speed compression damping is finally here. It does feel a bit soft on low speed compression, but it’s better than stock. Brake dive is now very manageable and the bike is much more composed. Increased feel through the front, which was expected. The thicker oil really quelled the pogo stick activity and provides good feedback. Is this ready to set lap records? No. But, for the money, the improvement is substantial.

Tomorrow will be the day to dig a bit deeper. So, in summation: sag ‘works’, 10 wt oil is a definite improvement, and the oil height is in the ballpark. After tomorrow’s note taking, revalving the stock internals is hot on the agenda.

On a separate topic…

Tech Specs. The results are really good on this bike. Some bikes don’t have enough coverage to really get the grip you need out of a set of tank pads. NOT a problem on this bike. Braking is effortless now (certainly combined with the firmer fork springs). Legs and knees feel velcro’d to the tank and really improve transitions and hard braking. As to be expected, of course. So for those on the fence, take advantage of the group buy. These will be in stock after the group buy, but now is a good opportunity to save a few bucks. Anyway, enough salesmanship in the build thread. They work. Me = happy.

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