Author Topic: Carb Rebuilding - Needle Jets, Jet Needles, etc (Read 7287 times)

jcmjrt · « **on:** September 30, 2005, 06:59:51 PM »

I'm wanting to put my Bandit in tip top shape and part of that includes rebuilding my carbs to last for the long haul. There has been discussion here of discontinued parts. There's a microfiche of parts on a sticky up top and there are three pages of parts for the carbs. I refer to the numbers from it. I called the local Suzuki dealer and Factory Pro and this is what I found. Reference number 12, Part Number 13383-10D10 needle jet is discontinued. This is the part that Factory Pro replaces with an adjustable needle in their kit. There is a part called a jet needle, Reference Number 28. There are three versions of this needle - one for model M/N, one for model P and one for California Only. The California Only model is discontinued. I've ordered the model M/N version and am guessing/hoping that won't cause issues as I do have a California model B400. Does anyone know what the differences are between the jet needles and performance implications?

I've ordered o-rings, diaphragms, springs, gaskets, jet needles (#28), and pilot jets to rebuild the carbs and make them fresh, fresh, fresh (I hope). After I finish hopping up the Bandit, I intend to get a Factory Pro kit and rejet which will the needle jet and main jets getting replaced.

The parts guy was very helpful and we discussed what parts are unique to the GSF400 carb and might cause problems in the FUTURE for availability. The parts that we identified were the jet needle (#28), diaphragm (#5), slide/valve piston (#6) and the float/needle valve assembly (#32).

If I have any problems getting any of the parts, I'll let you know.

b4cruz · « **Reply #1 on:** September 30, 2005, 07:24:59 PM »

the cali model has the can for emissions controls.
Get rid of it. Then set up your carbs with normal/stock
non-cali internals.

Are you sure the needles are that bad?
Most people have only done the O-rings
i mean if it runs good and starts up easy - why mess with it

Mine is a 91 non-cali with 20,000miles
and all it needed was a really good carb cleaning,
plugs and wires, airfilter, and a new 2nd gear

gsxr400 racer · « **Reply #2 on:** September 30, 2005, 07:55:33 PM »

CALI MODELS ARE SET UP TO RUN LEANER NO BIG DEAL SWITCHING IVE ORDERED THE P MODEL ONES SAME SAME JUST JET FOR !

jcmjrt · « **Reply #3 on:** September 30, 2005, 08:23:38 PM »

Quote from: "b4cruz"

the cali model has the can for emissions controls.
Get rid of it. Then set up your carbs with normal/stock
non-cali internals.

Are you sure the needles are that bad?
Most people have only done the O-rings
i mean if it runs good and starts up easy - why mess with it

Mine is a 91 non-cali with 20,000miles
and all it needed was a really good carb cleaning,
plugs and wires, airfilter, and a new 2nd gear

My main aim is to put the bike in new/better than new condition and have it last for a number of years in great condition. This is the bike that I love. I'll save any parts that aren't toast...and I'm contemplating what I'll lay in for the future. More parts are going to be discontinued as time goes on.....

interfuse · « **Reply #4 on:** September 30, 2005, 11:19:15 PM »

I think you're getting the jet needle and the needle jet confused. It's easy to do.

Don't ask my why -- but in the parts manual the "," means read backwards... Ie: Part 12 "NEEDLE, jet" is actually the Jet Needle. The JET NEEDLE is the the thing that looks like a needle.

Factory pro set comes with JET NEEDLES, but no NEEDLE JETS... Suzuki has discontinued NEEDLE JETS. Meaning, there's no easy source for them...

Once the weather here turns to total crap, I'll take my carbs apart and take the NEEDLE JET to the Mikuni dealer and see if they can match it. I'll keep you posted.

Edit: Re-reading Jays other message it sounds like he has a source... talk to him...

jcmjrt · « **Reply #5 on:** October 01, 2005, 01:13:41 AM »

I was confused but now I've got it straight. I posted this because I think that others might have been confused too. That's why I pulled out the parts page, talked with Suzuki and Factory Pro with the parts page in front of me and them looking at it online. The Reference Number 12, Suzuki P/N 13383-10D10 is what I'm talking about as being the part that is discontinued and is replaced by the adjustable needle from the Factory Pro kit (as per the Factory Pro rep who was looking at the same fische - we talked about reference number 12). You can call the part needle jet, jet needle or John Brown but names are much more confusing than discussing reference numbers or part numbers. When you order it's by part number and since it can be easily replaced with an aftermarket kit, I'm not worried any more. Factory Pro has an 800 number, they can pull up the parts Fische online and you can talk about it. 1 800 869-0497

Herr Tod · « **Reply #6 on:** October 06, 2005, 01:32:04 PM »

Does anyone know which jets are in the Factory Pro kit? I'm using #100 main jets and #32.5 pilot jets. This is the stock setting but the engine is running too lean. I had to raise the needles one clip to make it better. However this is not the way to do this so I want to order new jets. I was thinking of #102.5 main jets. I have also removed the snorkel from the airbox which causes a little less than 10% more airflow. Any idea's?

PitterB4 · « **Reply #7 on:** October 06, 2005, 01:45:03 PM »

Quote from: "Herr Tod"

Does anyone know which jets are in the Factory Pro kit? I'm using #100 main jets and #32.5 pilot jets. This is the stock setting but the engine is running too lean. I had to raise the needles one clip to make it better. However this is not the way to do this so I want to order new jets. I was thinking of #102.5 main jets. I have also removed the snorkel from the airbox which causes a little less than 10% more airflow. Any idea's?

For the US market, 102.5 was stock. The FP kit comes with 97.5 and 100, I beleive. The reason for smaller mains is a narrower needle. I'm honestly not sure of the pilot size.

Maniac · « **Reply #8 on:** October 06, 2005, 01:53:49 PM »

Quote from: "Herr Tod"

I'm using #100 main jets and #32.5 pilot jets.

My 32mm stockers had #97.5 mains and #32.5 pilots, whereas the 33mm ones had #112 mains and #32.5 pilots. The stockers worked fine, considering their condition, until they started falling apart on me. The 33mm carbs worked OK but the bike fell flat above 7000RPM, which I now believe was related to poor fuel delivery with the larger mains.

Oh, and the 32mm carbs had a jet-kit in them, stock mains were #102.5 for those as well. The #97.5 with the adjustable thin needle and the Slipon made a HUGE difference.

Herr Tod · « **Reply #9 on:** October 06, 2005, 03:18:40 PM »

I think I'll order #102.5. I have 33 mm carbs. #112 would probably work if K&N filters are used. Which main jets are in a GSXR 400? I know the carbs are not the same but it helps getting the idea.

Herr Tod · « **Reply #10 on:** October 14, 2005, 12:50:36 PM »

Now here's a mystery. After I removed the restrictors I found the bike running lean. I raised the needles one clip and it ran much better. Yesterday I have replaced the #100 main jets for #105 main jets. Started the bike and I found that it didn't go past 4000 RPM with the throttle fully open, it went past that with 1/2 throttle. It appeared to be running too rich, so I lowered the needles but this made matters even worse. I raised the needles again and installed the air filter. Problem solved... now I find this very strange because with the air filter installed it runs even richer.

I think the #100 main jets were the right ones, but I need bigger pilot jets because the problem is only below 7000 RPM. I also think the stock needles don't work with the bigger main jets. Any idea's?