Factory Pro 800 869-0497, carb kit, extended fuel screws, needle jets, RF900, Suzuki

Suzuki RF900R, 94-97

Item	Description
Long Boy Fuel Screw set pn: CRZ-SCR-SUZ-5020M $89.95 "finger adjustable at about stock prices" with 4 new screws, springs, washers and o-rings 1. Choose your shipping method 2.	"Long Boy" Finger adj. extended Fuel Screw Kit Frustrated with trying to find an "almost 90 degree" screwdriver to fine adjust your fuel screws for best idle and cruise? Use Factory Pro's new "finger adjustable" fuel screws to adjust fuel screws for best throttle response. Traveling to high altitude? It's easy to lean out the lowend temporarily. Make your life easier! Installation: Remove old short stock fuel screws, old orings, old washers and old spring. The o-ring might be stuck in the carb, so, take a light and make sure it's really out if it didn't come out with the screw (or you can't find it after you took out the screw) Use a small bent wire to pull it out if it doesn't drop out. Keep the old parts for "spares". Fuel screw assembly comes with: 4 Long Boy fuel screws 4 new o-ring 4 new washer 4 new spring
CRB-S79-1.0 $139.95 1. Choose your shipping method 2.	Adds more low-end / midrange, if the proper main jet is selected, more top-end power. Easy to install and tune - no slide drilling! Note1: When replacing a dj kit with Factory Pro components, be sure to replace the emulsion tubes with stock type, Suzuki tubes (available nickel plated from Factory Pro. The dynojet emulsion tubes will not work with standard needles. The Mikuni emulsion tubes have ID numbers and the dynojet tubes are not marked with any part number. Note2: When installing the kit, be sure to inspect the needle jets for wear. That's the needle jet - not the needle, itself. It's the brass colored tube that the needle goes into in the bottom of the bore of the carburetor. The RF900's Mikuni carbs wear out the needle jet orifice quickly and cause rich running at cruise and at full throttle. If the wear is slight, you will be able to lower the fuel level 1mm to 2mm to compensate, BUT! - the engine will ALWAYS run better with fresh, tight needle jets and a higher fuel level. That will allow the carb to deliver the proper amount of fuel in smaller droplets, which burn better and produce more power per amount of of fuel delivered - as opposed to the same amount of fuel delivered in larger droplets.
CRB-S79-1.1-TI $159.95 1. Choose your shipping method 2.	Factory Pro's Titanium needles and Stainless steel allen screws for the float bowls. Adds more low-end / midrange, if the proper main jet is selected, more top-end power. Easy to install and tune - no slide drilling! Note! When replacing a dj kit with Factory Pro components, be sure to replace the emulsion tubes with stock Suzuki tubes (available from Suzuki). If dynojet emulsion tubes will not work with standard needles. The Mikuni emulsion tubes have ID numbers and the dynojet tubes are not marked with any part number.
RF900 emulsion tubes pn: CRZ-EMU-100195K $132 for 4 1. Choose your shipping method 2.	Factory Pro designed PLATED emulsion tubes in stock, now. Plated for longer life. If your mileage was 40+ mpg and has dropped to under 30 in the last 3000 miles, this is where to look. Call 800 869-0497 to order.
RTR-SUZ-61-04 $89.95 Ignition Advance Kit out of stock 1. Choose your shipping method 2.	This Factory Pro kit rotor advances the timing 4 degrees. With stock engines with stock compression ratios, there is more power everywhere. Part throttle power is better - helping corner exit speeds. Improved in-town drivability.
SHFT-PRO-SUZ-4 $139.95 1. Choose your shipping method 2.	SHFT-PRO-SUZ-4 Factory Pro MicroBearing Detent Arm, Factory Pro Shift Spring and gasket. Installs in 1-2 hours - no case splitting required. Make shifting MUCH quicker and virtually eliminate missed shifts. This is exactly the same kit that Yoshimura Racing has used in the past.

Just to let you know I did get Mick Hones to do the work and source the parts (your new needle jets and carb kit).

They did a great job and the bike is running magnificently (I didn't realize how much it had deteriorated over time). Thanks for your help and advice.

Question:
Will advancing the ignition timing on my RF900 help full throttle power?

Answer:
Yes. Because Suzuki missed the MBT (Makes Best Torque) setting at high rpm by a bit on the RF900, advance the ignition timing 4 degrees and full throttle / high rpm power increases. Additionally, part throttle power is significantly enhanced - improving in town driving and off idle response.

Question:
What about part throttle power - like driving around town or exiting a 2nd or 3rd gear corners.

Answer:
At part throttle, the trapped compression is obviously less than it is when at full throttle (otherwise you'd make the same power at part throttle as full throttle). The pressures and temperatures inside the combustion chamber are lower and cause the trapped air and fuel to burn slower than when at the higher pressures and temperatures as under full throttle conditions.
For best power, the peak cylinder pressure must occur at a crank location that is very slightly before TDC.
To reach peak cylinder pressure at the proper location for maximum power, you should "light off" the mixture sooner so that it can reach peak cylinder pressure at the proper crank location, not later - perhaps after TDC!

Answer:
They do "get it right" - under their test parameters, their conditions, their requirements. Your requirements of increased power may, just possibly be primary for you - but only 1 factor of many for the OEM manufacturer.
On the other hand, perhaps there's a guy that mapped out the ignition curve or carburetion and he blew it...... It happens.
It's always interesting to do testing on a bike that's "wrong" then try to figure out how and under what test conditions that the manufacturers provided ignition timing curve or carburetion actually showed that the delivered settings were optimum.
Sometimes, the high rpm timing and carburetion is off - even to the point of 2%-4% down in power. That's not emissions because some of the worst bikes ended up getting much too rich at redline. Seems consistent sometimes - with one manufacturer's 600, 750 and 900 sportbikes all suffering from the same malady for a couple of years. The bikes remained unchanged until the models were replaced. They fixed the high rpm problems in some of their 98 models. Another manufacturer's 600 and 750 sportbikes had problems leaning out at redline in 93-96. The 600 was fixed, but the early 600's, when the 1.7-RK RaceKit was installed, swept the WERA Grand National Finals in Atlanta in 94 - however, the riders struggled with poor power over the whole year up to the Finals, where we installed the 1.7-RK kits. That same manufacturer's 750 had the same problem - and when fixed with the #1.7-RK Factory Pro Kit, won the A Superstock Class (1100cc upper limit).