Yamaha FJ1100, 84-85


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-Y07-1.0 $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.
Note: Inspect needle jets for wear!!!!! We have replacements in stock!

CRB-Y07-1.1-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.
Note: Inspect needle jets for wear before starting to tune!!!! We have replacements in stock!

$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.
Note! Really! Before trying to rejet these carbs - make SURE you inspect the needle jets for wear!!! We have replacements in stock -

$168 / 4pcs
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Poor mileage? Rich running at low rpm?

Factory Pro HDJ Emulsion Tubes (needle jets) - - - - - nickel plated for durability

Direct replacements in stock

replaces all fj1100 original part numbers:

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


Transmission Shift Improvement



(special order)

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Transmission Detent Arm Kit

Includes: Factory Pro Microbearing Detent Arm, Heavy duty detent spring and gasket. Makes shifting more positive. The slightly stronger detent spring rotates the shift drum quicker - 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 will not fix a damaged transmission.
If 2nd gear consistently pops out at full throttle, you probably need to split the cases, replace the 2nd gear shift fork, 2nd gear and the gear it mates with.

Hi Factory Pro guys!
I just wanted you to know that I finally installed the Special order FJ1200 Detent Arm Shift Kit you put together for me late last year.  It went in no problem, fit like it was OEM for my bike. (1989 FJ1200) It should have been OEM matter of fact! 
I had a chance to put the FJ thru it's paces on a 50 mile test run right after installing the kit. It is like having a *new* transmission!  Before i always had to remember to take care to get a good shift into second from first...and sometimes it would hang in neutral no matter what!  Guess what?  Problem G_O_N_E!  It shifts quick and smooth and sure with no more effort than with the stock spring & arm, maybe even less.  Be looking for more orders--i think some of the guys on the FJ board are very interested! :-)
Anyway, I had to write and tell you how happy I am--I could KISS you guys!  (don't worry, I'm a girl..;-)  anyway, you guys make any hats??  I'd sure be proud to wear one!  :-)
Thanks again!
...and wishing you a prosperous 2007!
Mardi Clark aka 'Kitkat'
ps: The GSXR jet-kit that my roomie (Jackie Gregory aka FastCat) bought from you for the 38mm "slingshot" carbs on the 1127 motor made her extremely happy as well!  Followed instructions, just dropped the kit in, and it runs perfectly well without any additional tweaking! Right on! You have two big fans out here in Tacoma WA!


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

Ignition Advance Rotor

no longer made - sorry
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!



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

Float Height Measuring
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 excess fuel to pass by the needle causing excess low speed richness.
The fuel will also consist of large drops, rather than small drops. Large drops of fuel tend to drop out of the airflow and not burn.
Check out Tech Section for "Needle Jets, Mikuni, worn"

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 -



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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!  

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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.
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