Yamaha FJ1200, 86-94

and Legend Series cars
(the "so good, it's illegal" jet kit)

Finger and screwdriver Adjustable "Long Boy" extended Yamaha fuel screws

Long Boy Fuel Screw Kit  $89.95
pn: 3020m1

 with 4 new extended screws, springs, washers and o-rings.

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"Long Boy"
Finger and screwdriver adjustable extended Fuel Screw

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!

Remove old short stock fuel screws, old o-rings, 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".

Each screw assembly comes with:
4 Long Boy fuel screws 
 4 new o-rings
4 new washers
4 new springs


Carburetor Tuning Kits

CRB-Y08-1.0  $139.95 
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STD drop-in carb recal kit

Boosts power a bit at full throttle, improves throttle response - especially at low rpm and part throttle, smoothing power delivery. Engine runs a bit cooler and usually smoother.

Comparison to dj kit: Much better driveability when properly tuned.

CRB-Y08-1.1-ti  $159.95
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Ti ProKit

Titanium needles, drop-in kit, uses Stainless Steel allen screws instead of zinc plated screws as in the #1.0 kits, otherwise, the same dimensions and jets sizes as the #1.0 kit.

Comparison to dj kit: Much better driveability when properly tuned.

$139.95 without filters
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Use if you remove the stock airbox and replace it with individual filters. Use with aftermarket exhaust, makes best maximum power.

Comparison to dj kit: Much better driveability when properly tuned.


84 Yam pn: 16H-14141-90-00
85-94 Yam pn:   50h-14141-92-00

$168.00  set of 4 pcs

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HDJ Style - patented
Hi Dispersal Needle Jet direct replacement for original parts for better mileage.

Ok - The average 1200 has accumulated a large number of miles - and by now, many of them have carbs on them that have really funky super-rich low rpm running "feature".
Symptom: Runs well when cold - but kinda stumbly mess when warmed up? Mileage 25 - 22 mpg?

Sound like yours?
Or - you are the best guy or the new guy at a shop, lowered the fuel level, dropped to smaller than stock pilot jets and put the needle in the leanest position - AND taken out the stock plastic 2.5mm plastic spacer and still can't figure out why the customer's bike is still spitting out more fuel than a blown up middle eastern gasoline pipeline?

99% of the time, on a high mileage 1200, the needle jet orifice part of the "emulsion tube" probably looks like an egg.
(needle jet wear, all carbs - click here)

That will allow too much fuel to rise up into the bore of the carb, decrease the engine's power and cause rich low rpm cruise and rich full throttle, low rpm running....     (Sound like yours?)

These needle jets are NOT what Yamaha would sell as replacements - They are full patented design that atomizes fuel to a finer degree - allowing a leaner burn w/o misfire and more power potential - along with 20th century improvements, like hard plating for longer life -

A suggestion? Before you start trying to make your FJ run right or even attempt to properly jet, replace the emulsion tubes.

Hi. First off, I`d like to say thanks for the FJ1200 emulsion tubes you sent. I had installed them and wow! What a difference! I`ve got back all of my missing midrange and fuel mileage. I guess it had deteriorated slowly to the point where I thought it used to pull harder than it does. I took a look at the emulsion tubes and couldn`t see any ovality but I took a chance and I`m glad I did. Just by changing the tubes I figure I got back anywhere from 30-40 km/tank.
Ray Tushingham
July 2009

Transmission Shift Improvement

SHFT-PRO-YAM-5   $139.95
(special order)
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Pro Shift Kit

F-Pro Microbearing Detent Arm
F-Pro Shift Spring
Clutch Cover gasket

Now that you've replaced the 2nd gear, it's mate and it's shift fork - Install this kit to make 2nd gear stay alive for years. Oh - nicer shifting, too.

Includes: Factory Pro Microbearing Detent Arm, Heavy duty detent spring and gasket. Makes shifting more positive at the expense of slightly stiffer shift lever action. The stronger detent spring rotates the shift drum faster, so the gears are more likely to engage under quick shift conditions. The Microbearing eliminates much friction, allowing the shift drum to rotate quicker for fewer missed shifts. Especially helpful in decreasing the 2nd gear and shift fork wear that the FJ1100's, FJ1200's and other bikes with large, heavy transmission gears are so well known for.
This kit fits both FJ1100 and FJ1200.

The shift mechanism is located under the clutch basket.
Kit installation requires removal of the clutch basket - using a 1/2" air or electric impact wrench and normal hand tools.



UPDATE JULY 2.012: after 10.000 kms the hard spring has just bed in and it is no more hard at all. The gear engage with less noise, less gearshift lever travel and more positive, resulting in a more pleasant riding, with less vibration, less effort on the up shifting and less worried about down shifting at high rpms. IT IS FANTASTIC!. RECOMMENDED



Ignition Components

(sample pic only)

RTR-YAM-6   88-94        $89.95
Does NOT fit 86-87 models

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Ignition Advance Rotor

Coupled with CRB-Y08-1.0, 1.1-Ti or 3.0 Carb Recal Kit, this advance rotor will improve throttle response. That equates to more "snap" in throttle response and better in town performance for you! Easy to install with normal hand tools -



Discontinued but we will re make if you can buy 25 of them



TL-float height gauge    $59.95
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The only way to accurately measure float heights. Works on nearly every carburetor.
More information on how to set floats, resultant fuel level, it's effect on low rpm fuel delivery, pictures.....
Float Height Page



main jets
pilot jets
carb kit

While we try to include enough jets in our carb recalibration kits to tune stock engined bikes, sometimes you riders and tuners just can't resist tinkering for a bit more power - and that usually means that you need different pilot and or main jets.
We have them in stock and ship daily!

main jets

Pilot jets

Main jet  #221 small, round slotted
Main jet #604 large round slotted
Main jet other types available  .
Pilot jet 30/96 emulsion type
Pilot jet  151/067 non emulsion type

Yamaha, fj1200, all years

84 Yam pn: 16H-14141-90-00
85 Yam pn:   50h-14141-92-00

$168 / 4pcs

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  Factory Pro
nickel plated
replacements in stock

HDJ Upgrade!

Subject:         FJ1200 Tuning
Date:               Sat, 20 Jan 2001 11:50:26 -0800
From:             "georgef" <georgef@c2i2.com>
To:                  <factory2@ix.netcom.com>

Thank you, thank you, thank you for your excellent site - who would have ever thought that lowering my float level .040" / 1mm would have transformed my bike so much.
1990 FJ1200
#45 pilot
needle #1170i-90q70rt
clip on /3 = center position
#132.5 main jets
fuel screws 3 turns out
Mid Arizona
70 degrees
1400 sea level
factory air box with six 1inch holes
K7N filter

Glad it all worked out, George. I think it's best to teach how to solve the problem!
Thanks for the feedback!


Feb 03,1999

I have a 1991 Yamaha FJ1200, and saw a tech article in Rider magazine about a problem that these bikes exhibit. At low speed, the throttle is nearly "light switch" touchy on my bike, and the article said that this was normal for FJ's but there was a solution. The article went on the explain that the FJ1200 has a very sharp ignition advance curve, about 33 degrees difference from 1000 to
2500 rpm. I checked the shop manual and saw that this was correct.

Rider magazine referred to your company as one offering a fix for this tendency. I checked your website and noticed that the FJ1200 was not listed (or I didn't see it) and was wondering if you offer an ignition advancer for this bike and at what cost. Also, do you know why the factory would put such a sharp curve in the advance of the ignition? Normally this is not a problem, but at parking lot speeds it can be quite a handful, as you can imagine.

Any help you could give me would be greatly appreciated.
Chris D.

Well, well, there's an FJ1200 page now!

Actually, the problem is twofold - the low-end carburetion is too lean and the ignition timing curve is pretty aggressive at low rpm.
Try adding the advance and see if that's enough. Adding the Carb Recal Kit and the advance will cure the FJ's "twitchy throttle" when properly tuned.

BTW - The FJ1100 needs the carb kit before the advance - as the advance alone will cause a light pinging at cruising speed when going up slight hills on the freeway.

Thanks for the question,

Tech Tidbits


Carb overflowing while sitting

Hi Marc,
thought I would update you on my carbs just as an FYI.  I was able to punch out the pins and remove the floats.  Cleaned the openings but had the same results, fuel overflow when the fuel pump turned on.  As is so happens, on this particular model of carb the entire needle valve assembly can be removed.  The needle valve assembly O rings had dried up and so the proper pressure wasn't being created in the fuel bowl due to the gas forcing its way around the bad rings.  I noticed that the valve assemblies were kind of loose when I wiggled them and that was when I suspected the O rings.  I've replaced them with similar size O rings and the problem is solved.
Thanks for the assistance and I hope this info comes in handy for someone else in the future.  I would never have found the problem if I hadn't been able to remove the floats.
----- Original Message -----
To: John
Sent: Friday, March 23, 2007 6:47 PM
Subject: Re: FJ1200 Carb problem

John wrote:
Hi Guys,
GREAT WEBSITE!!!!  I hope you can help me.  I'm experiencing a problem with my 91 FJ1200.  I've tried several time to clean the carbs with varying degrees of success.  I continue to have a fuel overflow situation.  I suspect that one or more of my float valves aren't seating properly to stop the flow.  The floats seem to be installed with pressed rods and I don't want to break something.  Is it possible that the floats are not removable?  This is the only part of the carbs that I haven't been able to remove and clean.  If I need a rebuild kit, how can I identify the carbs on this bike or is that an issue if they're the stock carbs? 
Hi John -

I use a very small punch and tap out the steel rod that the floats pivot on.
SMALL taps, as you CAN break the posts!
I've used a nail to tap the rod out, in a pinch.

Make SURE you are punching the right directeion -




Float Height Measuring

"touching, but not compressing the float valve spring"

Needle Jet wear
(sometimes called "worn emulsion tubes)
Inspect your brass needle jets for wear when you take out the needles. If the needle jets have oval wear pattern, they will allow too much fuel to pass by the needle causing excess low speed richness.
The fuel will also consist of more, large drops, rather than small droplets. Large drops of fuel tend to drop out of the airflow and not burn.
Check out Tech Section for "Needle Jets, Mikuni, worn"

Go to General Technical Support


Absolutely NO carb parts sold in California.

New and improved Suzuki Teka SFI  2

with new TPS display and "MMT" Memory Module Tuner

Finally - Quick, easy, cost effective Suzuki tuning with no expensive "add-on boxes"
Suzuki cruisers and sportbikes

Please click here for more info

Contact Factory Pro
M-F, 9am - 5pm, Pacific time, -7 or -8 GMT

800 869-0497
 USA and Canada

415 883-5620

parts information

EC997 dynamometer information

Product Support /Tech SECTION
click here


Mailing / Shipping address:

Factory Pro
101c Roblar Drive
Novato, CA

And most importantly
Restart back at the HOME page and click on the red box in the top left to find the bike that you want parts for...
restart at HOME page


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EFI and Carb Tuning - Most all FI and carb tuning

by Wheelsmith Racing

Flight Training - train with AMA race winner Todd Harrington.

The Harringtons own American Flyers, one of the most established flight training facilities in the USA.

 8 locations

The Rich Oliver Mystery School will help you discover your hidden inner strength. 
It will challenge you. It will teach you a new way of thinking, and a new way of riding. You can take your riding to an exciting new level!  

We use a variety of proven drills and training techniques. 
Practicing these techniques with our Yamaha dirt track trainers will enhance your abilities both on the track or the street.  

It doesn't matter what you ride or race, the Rich Oliver Mystery School improves everyone's skill level and mindset!

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(NEW!  Ask about the P-40 flights!)

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Just tell them that you saw this on the Factory Pro website!
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The extension of the laboratory for engines of the Swiss Federal Institute of Technology was completed in about 1935. Its architect was Rudolf Otto Salvisberg (1882-1940). He had a successful career in Berlin but returned to Switzerland after the advent of the Nazis. His architectural style was somewhat similar to that of Erich Mendelsohn. The staircase of the laboratory is in normal use but well preserved.
Edited to the tunes of Chemical Residue by Herbie Hancock.