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**SVSooke** · 02-14-2012, 02:26 PM

Jetting guru's can chime in but a Dyno-jet stage one kit is probaly what you need.

**cableguy** · 02-14-2012, 02:43 PM

DJ says you can use either stage 1 or 3 with your set-up. If you change the intake side to anything more free-flowing than stock you'll have to go with stage 3 or you'll be too lean.

Jet Kit for 1989-1997 Suzuki Katana 750

http://www.dynojet.com/pdf/3130.pdf

Dynojet Jet Kits Whether you run a standard motorcycle, or a tuned sportbike, Dynojet Carburetor Jet Kits can provide you with a simple and affordable solution to all your carburetion problems. Dynojet Jet Kits increase power and smoothness throughout the entire rev range, while maintaining optimum fuel economy. Each Dynojet Jet Kit includes comprehensive instructions which show step-by-step installation and testing procedures to ensure a perfect setup every time. This is backed by free telephone and Internet support to Dynojet customers. Kit installation and Dynamometer services are available in many parts of the world. Please see the Dynamometer Center Search Page to locate your nearest dyno shop. Read Full Description Jet Kit Types Needle & Needle Jet Caps Many newer bikes have very flat power and fuel delivery curves when used with the stock exhaust and air-box. When aftermarket pipes are used, the power curve is usually not flat. You find the need to lean out for low speed and richen up for top end; or leaner on the top end and richer at the low speed. In order to achieve full function and driveability, Dynojet develops shrouds or cap style nozzles for adjusting the upper or lower top end. They also have an effect similar to fuel injection by breaking up the fuel as it enters the air stream. Fuel Needle The design of the needle is where Dynojet spends most of its R&D time. The needle is designed to give the correct amount of fuel throughout the mid-range and is also designed to allow adjustment from groove 1 to groove 6 with little or no effect below 3000 R.P.M.; then with the correct end dimensions, the needle will have little effect on the main jet regardless of needle position. This isolates all circuits from each other and ensures easy set-up of the midrange and driveability. Main Air Jet This jet allows air into the emulsion tube to mix with fuel being drawn up from the float bowl. It controls the amount of fuel which can be pulled from the float bowl into the venturi. The larger the size of the main air jet, the more air you get and less fuel. The smaller the main air jet, the more fuel you get and less air. Dynojet alters this only to achieve the flattest possible fuel delivery curve. Pilot Circuit This controls 100% of the engine idle and 25% of the transition onto the needle. Dynojet has found that the engine will idle with the standard pilot jet, with or without the air-box and with the slides and needles removed from the carburetors; therefore we never change the pilot jet. Doing so is proof that you are not using the other circuits correctly. Idle and off idle is controlled by the mixture screws and the float level which have the most positive effect below 4000 R.P.M. On some models the pilot air jet is changed to provide optimum fuel economy. Correct balancing of the carburetors also ensures a smooth idle. Main Jet We develop our main jets to correctly serve two functions; static load and dynamic load. The static load is the fuel received through the main jet in the upper gears, where the tachometer is moving very slow. The dynamic fueling portion of the main jet is the amount of fuel received from the jet in the mid-range potion of the power. For example, you have a GSXR1100 G,H with #130 main jets. You then install #125 mains. After running the bike you notice the top end has improved but the mid-range doesn't pull as well. You then install #135 mains and you notice the mid-range is great but the top end is slower. This is a common compromise when using stock main jets and needles. If you install Dy 93 Dealers Orders Dealer Orders "Dealer Orders Dynojet Research Inc. dealers much call in to place an order. Please call us at: 1-800-992-4993 (Toll Free)/Suzuki/Katana 750 (GSX-750)/1997

Or you can search the GS database for the jet chart and order what you need. You can't go wrong with the DJ kit though. It's complete with new needles, and really good support from what I hear.

Happy jetting!

JJ · 02-15-2012, 05:23 AM

I'd suggest the Dynojet kit, too. You will still have to fine-tune it with some plug chops, but it will get you there faster and easier

**trevor** · 02-25-2012, 10:48 PM

So I got the pipes on and with some carb adjustment it seems to be running great. No flat spots. I have not put in a jet kit as of yet. I have been monitering the plugs and they all look really good (dark not lean) except plug #2 it is pretty white. I have backed the carb screws off and readjusted so that they are all the same adjustment. Number 2 carb screw was a little leaner setting. So went out for a test ride and the #2 plug still is white. Anyone have any thoughts? I'm pretty new at this and had the help of fellow GSr AZR.
Thanks

**Nessism** · 02-25-2012, 10:55 PM

Get that Dynojet kit. It's important to not run the bike lean because that means hot.

hot = bad (for air cooled motorcycles)

**trevor** · 02-25-2012, 11:12 PM

Originally posted by Nessism View Post

Get that Dynojet kit. It's important to not run the bike lean because that means hot.

hot = bad (for air cooled motorcycles)

Thanks Nessism gonna get one right away!

**trevor** · 02-25-2012, 11:21 PM

here is a pic of what my plugs look like now...

**1980GS1000E** · 02-26-2012, 12:23 PM

Looks ok. Maybe get an IR thermometer and check the head pipes too..

**azr** · 02-26-2012, 09:47 PM

Don't mean to be jumping in the thread here but being I have no experience jetting for 4 into 1 pipes I've got some questions I'm dying to get figured out. Before Trevor put the 4 into 1 on I looked at his plugs and they were all lean, not a spec of brown/black or carbon...but the bike ran great, no hanging, flat spots, etc.. Stock pipes with a K&N filter. He put the new Vance pipe on and immediately 3 plugs changed colour. # four looked great, nice brown, the other two a bit more to the lean side but still not a bad brown and then #2 is as lean as lean can get and hot, the electrode is showing signs of being too hot. So here lies my confusion. With the first plug colours I couldn't figure out why they were looking lean yet the bike ran great. With the plugs after the new pipe was put on I was expecting to see all the plugs looking like #2, lean colours and signs of being too hot...but 3 out of 4 are not. Now Trevor hasn't pulled apart the carbs so there is no telling what jets are in there of course and I know that could be the answer to all of this but any ideas to cure me of these questions rolling around aimlessly in my head would be greatly appreciated.

**Steve** · 02-26-2012, 10:58 PM

Originally posted by trevor View Post

... I have backed the carb screws off and readjusted so that they are all the same adjustment. Number 2 carb screw was a little leaner setting.

What "carb screws" did you turn? Which way? How far?

I ask, because the only external adjustment on your carbs is the "IDLE MIXTURE ADJUSTMENT SCREW", which is pictured below:

Turning them out to the same number of turns is only to get them to a starting point from which you will do some fine-tuning. Most of us recommend starting with three full turns to make sure your mixture is rich enough to start and run properly, then, when the bike is fully warmed up, slowly turn each screw in, listening for the point where the engine either runs the fastest (it won't be much of a change) or starts to decrease. If you get to the point where it decreases, back the screw out about 1/8 to 1/4 turn and go to the next carb. Due to differences in the tolerances of individual parts in the carbs, there can easily be 1/4 turn difference from one carb to another.

By the way, turning the screws OUT (anti-clockwise) will richen the mixture, turning them IN (clockwise) will lean it, and this is for the IDLE mixture ONLY. That circuit in the carb is only good to about 1/4 throttle, so it is responsible for most of the low-throttle operation, too.

If you have only done your testing at low-throttle settings, it will not be obvious that you need to change your jetting. It is your MAIN jets that need to be changed, they don't even get used until over half-throttle. If you do some 3/4 to full-throttle runs with your stock jets, you can probably plan on replacing pistons and cylinders, too.

.

**paco13** · 02-29-2012, 07:11 AM

#2 supplies vacuum to petcock, maybe a leak drawing air in. Are carbs clean, could be something clogged also.

**trevor** · 02-29-2012, 11:32 AM

Originally posted by paco13 View Post

#2 supplies vacuum to petcock, maybe a leak drawing air in. Are carbs clean, could be something clogged also.

I ordered the stage 1 yesterday from Z1 enterprises so with help from AZR I'm going to have a look at what I've got going on in my carbs later today and have it ready to install the kit. Also got progressive rear shocks showing up today.
Boy it sure is easy to spend money!!

To everyone who has responded thanks very much and I will keep you posted on how she is running.

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