What jets should I get?

[drivingbored]

I bought a 1993 fj1200 abs from a man in Texas with 23k miles on it. It already has a suppertrapp 4-1 exhaust and when he sold it to me he gave me 2-1 foam pod filters. I need to know what size jets I should run and how much I need to shim up the needle jet for these mods. I'm a novice when it comes to carbs.

[fj1289]

Use the search function

Don't you hate it when asshats at most sites respond with that?!  (Also, to be honest, the search function here does leave a bit to be desired...)

Seriously now - welcome to the site!

I went through the files section - and I don't think we have a single comprehensive/concise post for this - lots of good info, but it is still a bit of a hunt.

Here's a hodge podge of info for you - only thing I really didn't get a good post for was shimming the needle.   I'm sure Robert or Randy from RPM (banner up above) can help you out - they know these engines well.  Also, where are you?  Elevation will make a difference in the recommendations too.   And make sure you confirm there is NOT a jet kit in your carbs before you follow this jetting advice.   Different jet kits have different style needles that will make a BIG impact on the main jet size!  This assumes the stock needles!


Jetting info that seemed closest to your setup:
http://www.fjowners.com/index.php?topic=1974.msg19698#msg19698

New setup
Supertrap full stainless 4-1 pipe
UniPod filters
Main jets 117.5
Pilots 42.5
Needle 5Fz272 (stock)
Air 155 (stock)
Needle clip pos. 3 (middle)
Air screw 2.5 turns out.
Float height 21mm (lowered 1mm)

Blip test was hanging slightly, so I turned air screw out to 2.5 turns.(started at 2) Comes right back to idle. Re-Synced carbs.
After 1st test run :
Ran great. Low end and middle throttle response muchly improved. Driveabilty(is that a word?) is excellent. No hesitation from low rpm right through to redline. Pulled hard and steady.  Maybe a little flat at top? (bigger mains? 120) is ok for now. Will ride a bit and tweak from here if need be. Check plugs after a ride or two. I think it is real close right now. Will have to check mileage.


Initial setting for idle mixture screws:
http://www.fjowners.com/index.php?topic=18722.msg189454#msg189454

Fingernail setting for idle mixture


Adjusting the idle mixture:
http://www.fjowners.com/index.php?topic=19852.msg203332#msg203332

Blip test

[drivingbored]

I live in south Arkansas so my sea level is 312ft. The whole bike is stock except a Corbin seat and the supertrap exhaust. The guy before really didn't take good care of the bike and I get pops and bangs on deceleration from it not being tuned after install. From what I have been looking at I might try a main jet 117.5 a pilot of 40 and shiming the stock needle .05mm.

[Pat Conlon]

^^^ That sounds perfect....