Saturday, November 21, 2009

Yamaha FZ1 Gen II technical

My findings about not very well documented stuff will appear here. They are subject to change. Updates every weekend until my setup is perfect.
Check out these pages for guidance:
London Bikers, suspension setup demystified and

Riding style and conditions: Commuting to work, either 15 minute ride through town or a 10 minutes on the freeway. Occasional wheelies to remind myself that fun's not over yet even though I'm 30+. Occasional 15-20 minutes of freeway ride, and B-roads every weekend or so in the summer.

5,0L/100KM Highway easy riding
8,6L/100KM Town commuting

Weight savers:
Removing the tools and center stand saves 1,3 Kg. The OEM silencer weighs 7 Kg, and replacing it with a Yoshimura TRC steel sleeve slip-on saves 3,5 kg. Removing the centerstand also makes getting the sidestand out easier.

Suspension adjustment
Rider weight: 110 KG + gear = 123 KG
Suspension adjustment fork:
Preload adjustment:
One+ spring preload indicator decreases fork travel by 8mm. The manual indicates 5,5 "clicks" as standard, 6 is too soft for me, the bike dives too much.
Setup scenario: I want my bike to be a bit stiffer as for inspired backroad driving, somewhat like a sports bike, but not as a bench (read: Ducati)
5 is firm-ish, but it looks like there's too much travel way left, about 50 mm by eye-measure.
With the spring preload at 5, You will feel potholes as with a german car with stiff springs. The fork will be a bit stiffer, the bike doesn't dive as much under braking, and the ride will be comfortable enough. This setup will swallow speed bumps at ~40 km/h without a problem.
You might want to try 4,5 or 4 to harden the preload, and make the bike dive even less.

Compression damping: (left fork leg)
Standard is 5 clicks to the left. My setup is 6 clicks to the left. You'll want at least 6 clicks to the left if you're doing wheelies all the time. Landings are pretty hard otherwise.

1 click to the left is megastiff, like a bicycle. Speed bumps will be rock hard at 35 km/h.
26 clicks to the left will feel like you're jumping in bed, a jump, and you go up and down on the springs a couple of times. This will swallow the speed bump softly, but you'll bounce up and around after impact. Terrible sensation.

Rebound damping: (right fork leg)
Standard is 18 clicks to the left out of 28. My setup is 18 clicks to the left.
The standard is good for street riding, I don't feel the need to change it.

Suspension adjustment rear:
Tried 1+ preload, 10+ rebound. Bike spins on full throttle. Rebounds are too hard, you feel shocks in your back , even with smaller obstacles
Current setup: 3+ preload, 8+ rebound - default

Spring preload:
Standard is 3 clicks, I run with 3 atm. I tried 1 click
Rebound damping:
Standard is 8, I tried 10, and the rebounds were a bit too hard, I felt the shocks in my back. Slower rebound can adjust chassis pitch, and slow down weight transfer to the front.

Also make sure You read the suspension setup info at the following pages: (for Fireblades)

Fuel gauge issues
The fuel gauge stays at 100% for over 90 km, then suddenly drops to 50% and then makes another sudden drop to the reserve. This was resolved by changing the fuel pump unit which has the fuel measurement unit incorporated. Now the gauge goes to
-1 dot after ~40 km
-2 dots after ~70 km
UPDATE: My Yamaha shop changed the fuel pump unit, which has the fuel meter incorporated, on the extended warranty. It's all good now!