up FZ-1 Carb Kit
Part # FZ-0102SO...$120.00 For
off road use only
(best bang for the buck)
Part # FZ-0102MB...$120.00 For
off road use only
Requires K+N air filter
(slip-ons show no gain over part #FZ0102SO with this kit - except with
ported intake boots)
These kits were the
result of 6 months of testing and were designed into 2 kits:
Part # FZ-POD... $ 295.00 For off road use only
Carb Kit only $120.00
Custom Velocity stacks - (not available separately without kit)
FZ-PB Ported intake boots - *Discontinued*
These hand ported intake boots for the 2001-2005 FZ-1...
These boots will give a solid 5 hp gain above 8000 rpm with no losses
in hp at any point of the rpm range - no sacrifices !!
THIS IS THE MOD THAT ONE OF OUR COMPETITORS DID TO SHOW GAINS ABOVE THE
AIRBOX WITH POD FILTERS - BUT HE DOESN'T TELL YOU THAT.....
DIY instructions can be found here: http://www.yamahafz1oa.com/forum/showthread.php?t=47373
THE TRUTH IS, PODS FILTERS WON'T MAKE ANY MORE PEAK HP THAN THE AIRBOX
ON THIS BIKE.
THIS PROOF CAN BE SEEN ON OUR - fz1dyno2.htm
You must have our MB kit or Pod filter kit to get
the advertised gains - works with slip-ons and full system equipped bikes...
No jetting changes needed when using these ported intake boots with
our carb kits
One for any slip-on muffler and another for a Full 4-1 w/merge plate or
4-2-1 exhaust system.
The reason that we made two different kits is due to the dramatically different
scavenging characteristics of the two different configuration exhausts. Also
Full system applications will benefit from less intake restriction above
Continual testing has shown that a specific type of air filter cover modification
will produce a significant gain above 9000 rpm with no losses to driveability
in a Full exhaust application.
After all, if you went with a Full system on your FZ-1, you are looking
for every last hp that is available. With this kit, you are sure to get
The Full System kit (FZ0102-MB) is designed for a 4-1 w/merge plate exhaust
and also SMALL VOLUME 4-2-1 systems, with a secondary section less than
8 inches long. It has been designed with BOTH the Yoshimura Duplex Race
exhaust AND Akrapovic Full Race pipe. It works awesome with both pipes.
We have tested this kit with the Muzzy 4-1 full system as well, with excellent
results. The kit contains instructions on the necessary air filter cover
We now have a pod filter kit available for the FZ-1, it utilizes K+N dual
oval pod filters and our own velocity stacks to help boost midrange power.
Dyno charts can be seen in our comparison section below.
Typical results for the Slip-On Carb Kit and Slip-On exhaust are appx. 9
hp with a nearly flat torque curve and a dramatic midrange increase. This
is due to correction of a poor fuel mixture and reduction in backpressure
of the stock muffler.
All of our carb kits for this bike will eliminate all surging and excessive
vibration problems associated with this bike.
Why buy this kit instead of another brand ?
My FZ-1 Carb kit is designed to enable the carburetors to deliver the
maximum performance and efficiency that can be obtained.
The factory compromises for emissions and fuel economy (stock needles) are
replaced with new needles for optimum performance at all rpm and throttle
The FZ-1 has several carburetion problems in it's stock form. My kit takes
the approach of fixing all of these problems at their source. There is also
no need for any additional 'tuning' after installation. The thorough R&D
on the kit makes it truly 'plug and play'. Just install it and go.
Vibration at light steady throttle:
Most noticeable in the 3800 to 5000 rpm range.
This is due to the excessively large spacing of the three pilot bypass holes.
The throttle plate has to uncover the next hole before more fuel can flow
from this circuit.
Fitting larger pilot jets will make no difference to steady state operation
at light throttle due to the fact that the next hole is not yet uncovered.
Raising the needle does not help because the throttle plates have not been
open far enough to expose the needle circuit during light throttle cruise.
The result is surging and buzzing that cannot be eliminated without modifications
to this circuit.
Our solution is to:
Enlarge the pilot bypass holes. Enlarging these holes in the throat of
the carb makes available just the proper amount of additional fuel volume
at exactly the correct throttle opening.
Adjust the mixture screws for a richer mix.
Synchronize the carburetors.
Dynamically adjust the throttle position sensor. This also contributes to
the smoothness and takes care of all the ignition timing issues under 4000
Flooding when parked overnight causing the throttle to be partially opened
when starting cold with the choke:
This flooding condition is due to excessive fuel in the carburetor's
float chambers which overspills slowly when the bike is parked. The cylinders
become 'wet' and slightly flooded, causing the rider to be forced to open
the throttle slightly on a cold start with the choke. With the jet kit installation,
the floats are readjusted to alter the fuel level thusl vastly improving
Stock jetting causes an overly rich fuel fuel
mixture at full throttle above 8000 rpm:
Full throttle operation with stock jetting above 8000 rpm is overly rich.
In order to correct this problem, smaller main jets are supplied optimized
for use with the needles that come with the kit.
The original main jets that come with the bike are of a different size on
cylinders 1&4 as compared to 2&3....
Repeated dyno testing and exhaust gas analysis has shown a higher and wider
power peak as well as a more consistent fuel mixture throughout the rpm
range at full throttle with these new main jets.
All of these tests were comfirmed by road testing against another bike under
Excessively lean fuel mixture at part throttle
at any rpm:
The area of part throttle lean condition can only be fixed with a different
needle taper. The single, very shallow, taper of the stock needles simply
cannot cope with the fuel requirements to keep a consistent fuel mixture,
making more heat, vibration, and lazy acceleration.
My custom needles have five separate angles in their design to give the
most consistent fuel delivery possible. The result is a seamless power delivery,
excellent mileage, and smooth driveability in normal everyday use with no
sacrifice in top end power or midrange roll-on.
The needles that were chosen are the result of exhaustive testing in all
kinds of weather on the road and on the dyno in conjunction with exhaust
gas analysis. Over 70 different prototype needles were tested before settling
on the ones that come with My kit. Over 900 dyno runs were logged as well
during development on carburetion tests alone.
Lazy throttle response throughout the rpm
range as compared to the R1:
The stock FZ-1 has lazy throttle response due to heavy slide springs
that control the vacuum pistons (carburetor slides).
By clipping the springs to the desired tension, throttle response will become
instantaneous and the delay on full throttle shifts will be eliminated.
The result is a much more responsive engine.
By enlarging the slide's air displacement holes, you will be allowing them
to lift and return a little more quickly, and also to match the new spring
tension, and provide the desired improved response.
Other kits that use the stock needles
with an airbox mod will have excessively lean fuel mixtures at part throttle
and at full throttle operation throughout the midrange....
(4500 thru 9500 rpm at throttle openings larger than 20%)
Causing a/f ratios to be leaner than 16-1 and getting as lean as 18-1 in
This is due to the fact that the stock needles cannot supply enough fuel
at part throttle with an un-modified airbox with stock jetting... let alone
a modified airbox with reduced main jets.
Installation time for this kit is just 15 minutes
more than any other kit.
See the review
of our Slip-on kit in :
- January 2003
News - July, August ?? 2004
This is an R1 motor. Ignition advancers are not
recommended unless you have significantly raised the compression!
See our dyno test on This
Ivan's Rockland County Motorcycle
175 N. RT 9W Unit #1
Congers, NY, 10920
Mon - Fri 10am-6pm
Sat 10am-2pm Eastern Time
Dyno Charts View
Kit Photos FZ-1
Air Induction Removal Kit
Engine Kit Charts (discontinued)
FZ-1 ignition timing tests & additional dyno charts
Jet kit comparison page
(See this page for comparison to other brand jet kits)
i t p h o t o s
y n o c h a r t s