By: Frank Hartung

Part I - February 1998 - Zx-11 Stocker
Part II - January - 2000 - ZX-1109 Modified

The following is a rundown of the changes and improvements made to my 1992 Zx-11 over a 6 year period. The products that I use and /or suggest are based on trial and error and experience. I have gained my knowledge through many years of wrenching on my 1969 Ford 428 SCJ Fairlane Cobra N.H.R.A. D/Stock Eliminator drag car.

Ford Fairlane Cobra, May 1994


In this class of racing there are strict rules on what can and cannot be used or modified. You must use bone stock heads, intake, carburetor etc. So to make more power one has to learn all the tricks and fine details. I applied this to the Zx-11 with the goal in mind of maintaining reliability, comfort, and speed ( of course ) with No cost / Low cost as a guide line.

I will list all of the changes that have been made over a five year period in order of the Kawasaki Zx-11/ZZR-1100 service manual chapters as this will make it easier for you to look at a certain systems or area of the bike. Whenever possible I'll list the costs, work involved and effects in power and/or handling. Also any weight removed, I'll list pounds and ounces as applicable. Any area where I haven't made any changes, where possible I'll suggest up-grades that I would do if I had the bucks.
Some of this information is general and other is quite detailed.

Enjoy and please feel free to e-mail with your comments and ideas.

Poor man's ignition advance - take your stock advancer out. Looking as if it is installed on engine, file the right side of the slot .032". Use Loctite and reinstall so the filed side of the slot is on the split pin.(counter-clockwise). Hold advancer firm as you tighten bolt. Just saved $90 Canadian and you have 4 degrees more of advance.

 

 

Weight as of May 1999 in light mode - full of fuel - 525 lbs.  No fuel - 493 lbs.

 

Still no Titanium in/on the bike, but the wheels sure helped.

-Throttle grips and cables - make sure throttle plate open fully
-Choke cable - fully opens
-Good and clean fuel filter
-K+N Air Filter - you do have one don't you?
-Fuel level sensor; C-model. (flashing lights):

I could give you my settings or tell you to buy this jet kit or that, but if you are really serious about setting up your carbs, then I suggest that you buy an air-fuel monitor kit. It usually comes with everything you need ( gauge, oxygen sensor, and fittings.)
Drill a hole six inches or so from the collector, weld in the fitting, wire in the gauge, go for a ride and it will tell you what the carbs are doing.
Best power is arguably 13.2 to 1. That is if everything is 100%. Having said that, I recommend 12.2-12.7 to 1. Adjust your main jets first. 8000 rpm and above in the higher gears. (3-4) Then the idle screws, and last the needles. Trial and error is the rule of thumb here. What you want is as close to a steady reading as possible. Needle and mains are checked at Full throttle. If the readings are higher than 13 to 1, it is time for a change.

 

-Keihin 148 jet flows as much fuel as a dynojet 140 jet (all things being equal)
-Keihin jets flow is progressive
-Dynojet jets flow more fuel in the 4000 - 8000 range compared to the Keihin jet
-Remove air screen.
-C - model - Ram-air needs to be opened up at least 1.5 sq. ins. at the front (2 sq. ins. would be ideal) with a minimum of 7.8 sq. ins. throughout the snorkel / airbox system.
-D - Model - Ram-air is just fine. but the tubes are limited to 6 sq. ins.  There is still something to be had there.  I would loose the screens though!

 

 

Final jetting for a 1109 with 12.2 to 1 compression is 158 keihin jets. Used a Dynojet jet kit for a D-model because of the stepped needle.  This with the airbox and snorkel mods allows for a 12.2 to 12.7 A/F ratio from off idle to redline.  Idle screws are 2 3/4 turns out and the needle in the fourth slot from top with one shim under it. (3 1/2). 

 

This is when you are looking for the last one half of one percent of available horsepower.  I did a little research and found that the local fuel stations 92 octane has a distillation curve of Initial boil of plus or minus 105 degrees F and 95% boiled off at 380-400 degrees F.  That means that the fuel has to reach a temp of above 400 degrees before the fuel 99+ percent of the fuel is in gaseous state(pun intend). 

 

Aftermarket fuel-i.e., VP or ELF or what have you racing fuels have a better quality components of fuel that are "brewed" to meet a specific blend that is far superior to pump gas.  Pump gas is made up of low and high grade to meet a octane rating.  It may be 84 octane in one area and 100 octane else where. Combined they "average out" to 92 octane. This is just an example, but this is what you get at the pump gas station.  They do add allot of other products to help reduce emissions, carbon build up, varnish,  etc.

 

I like to use VP racing fuel. The grade I have at the moment is MR8. This is a leaded fuel that has a distillation curve of 103 degrees F initial boiling and 95% boiled off at 203 degrees F.  In 100% fuel load it caused a excessively rich mixture as it was soggy.(I removed the O2 sensor as lead and O2 sensors do not mix).  I figured that a 150-152 main jet would have probably taken care of the mixture, with probably some movement in the needle to finish it off.  As this fuel is relatively expensive, I decide to use a more friendly approach of mixing it at 10% VP, 90% pump gas.  This worked quite well and was very noticeable at 3000-5000 with a greater tendency to wheelie, and pulled very clean on top in all gears.  The next batch I will be using VP's C-12 racing fuel.  It is less expensive and more readily available than MR8. 

-always use distilled water
-run at least 50/50 antifreeze.
-redline water wetter
(product that causes water to lose its surface tension)
-160 degree thermostat
-100 ohm resistor across temp gauge to give more needle movement
-exhaust header wrap - also saves legs in summer
-water pump bearings failed at 65,000 kms. repaired myself at a cost of $65. new pump cost $230.(Canadian funds)

Note: this is the Zx-9R plug. It has dual electrodes and will last at least twice as long as the stock plug plus more power. Torque plugs to 10 lbs. and use anti-seize compound on treads sparingly.

Split Fire Plugs - I glazed a set after only 12 passes at the drags.

Note: if you do your own adjust, make sure you do it at the same relative temperature to get accurate measurements.

This is very time consuming and involved procedure, but well worth it if you are able to do it yourself. Factory tolerances are anything but okay. The new or present setting that I am using I got from Muzzy (thank you).

From actual settings to Muzzy's settings was a change of the intake 6.5 degrees advance and the exhaust 6 degrees advance. This helped right across the power band. It is no problem slotting the stock cam gears. You will need to spot face the slots so the bolts will sit flush.

Rob Muzzy/Doug Meyer have been using cam timing in the 102/104 exhaust to 105/105 intake/exhaust. I like the 102/104 because it builds low to mid range power.  Since I am running 41 rear tooth at sea level and 42 rear tooth at elevation, from stock 45 tooth, it does help running the advanced intake timing. 

The valve can go away after 60,000 kms or so.  I had to replace 4 intakes and 3 exhausts.   Also 4 rockers were done.  Everything else was fine.  I used the 1109 head gasket as a template and massaged the combustion chamber accordingly.  Also cc'd the head so it was even across the head.  Final compression with 1109 kit was 12.2 to 1. Also took a small cut on the head of 0.015".  With the new pistons there was plenty of valve/piston clearance.  Something I found out was the wiseco piston pin is 10 grams lighter than stock. So if you ever have to take it apart and going to use stock pistons, you can decrease the overall weight.

I replaced the street baffle with the race baffle. I cut the race baffle down about 6 inches and reinstalled it. This keeps the oval third chamber intact and helps with the noise. It is noticeably louder, but not annoying. After 20,000 kms the packing was still good. Saved 7 ounces and increased power everywhere.
Haven't done a dyno run with race baffle installed, but in second gear can put front tire anywhere I want. Never been able to do that before!

This is something to do when you are changing the exhaust pipe or the gaskets. With the engine still in the frame, but all the stuff remove in front of it. ( rad, oil cooler, fender, wheel etc.). Make sure the valves in the port you are working on are closed. Take a little vaseline and smear it in the port near the valves, followed by paper tissue or towel. Then a liberal amount of vaseline to seal off the port, but away from the opening.
If you run your finger in the port opening, there is a ridge at the opening. Each port has a different flaw. So you have to port accordingly. You DO NOT want to open the port anymore than necessary, just make all the ports at the opening ( quarter inch / 7 mm. ) the same. Just remove the ridge. Remove all the aluminum filings and clean everything up.

 

 

Raised the exhaust port and filled in the floor.  Need I say more!!!

Note: This can only be done if a V+H pipe is used, as it is the only pipe of 1.550 inside diameter..

This is a 2 inch wide heat resistant tape that is wrapped around the primary tubes and at least the collector. This keeps the heat in the pipe and out of the engine cowlings, rads, etc. It causes a stronger signal at the carbs and therefore a stronger throttle response. Also helps the engine run overall cooler and keeps heat off the legs on hot days.

One of the strongest in the business. I am still using the original steel and fiber plates. As the power started to increase with modifications, the clutch would slip at redline while doing a clutchless shift. With 43,000 kms on it, I thought the clutch was toast. The clutch was perfect, no wear except for a couple of blue spots on the steels. I replaced the springs with Barnnett springs and no more problems until 64,000 kms when it did the same thing ( I had found some more power over the years ). I then up-graded the springs to EBC springs ( Stiffer than the Barnnetts).
At this time I noticed that the needle bearing and hardened washer on the clutch release plate had worn out. Cost $20 to replace.
One up-grade that is amazing is replacing the steel plates with some custom Aluminum plates. They are 1.4 pounds lighter than the steels. This is I think to be the best bang for the buck modification that is available. (for those interested, e-mail me). I haven't dynoed yet, or 1/4 milled it, but I think there will be a .1 to .2 sec improvement. I'll update as soon as I find out.
Replace the clutch fluid once every 2 years is fine, unless you store your bike outside, then once a year is recommended.

After break-in, I have only used either a semi-synthetic or fully synthetic oils. Presently I am using 10W40 Motul. I find it shifts the best with Motul. Never use a automotive oil as it is not designed for tranny's. ( I know there is a lot of controversy about this, but this is my belief ). I don't recommend any "SAE SH" or "SJ" oils as I heard that it may cause problems with stock clutch plate ( read slippage ).
Kawasaki recommends at this time "SAE SG" grade oils.
If you are running your balancer, I would recommend using a 10W50 oil. Especially if you are running in the 5 digit RPM's. The balancer is running in the oil and causes it to aerate the oil. I believe this is the cause of the # 3 rod failures in the Zx-11 motors. The balancer gets its oil from the same passage as the # 3 rod. Add a long, high, 1-2-3 wheelie and I'll bet dollars to donuts that you can kiss the rod good-bye.( This is solely my belief and not confirmed by anyone)
For more info check Q+A site Removal of Counter-Balancer:

 

On 1998 and newer Zx-11's, Kawasaki up-dated the oil pressure relief valve to a piston type plunger and 4 holes, instead of a ball and 2 holes. Go to the dealer and put the new relief valve in while you are pulling your balancer.  The Kawasaki part # is 16130-1058.

 

If you are rich, replace those engine mounting bolts with Titanium. Cost about $700 for a couple of pounds. 

If you ever have the engine apart, have the crank lighten up. Valley Crank of Florida will remove 3.2 lbs, balance, and knife edge it for a gain of 10 horsepower, and make it rev like a 2 stroke. I haven't done this yet, but will as soon as the motor comes apart for a major rebuild. Costs about $1000 U.S.
Removal of balancer at this time is a bonus, if you haven't done so already. The balancer is worth a 2-3 horsepower gain. In first and second gear it feels more like 10 horsepower. ( For more info, see section 6. Engine Lubrication.)

C - model 2nd gear is a 2.00 to 1
D - model 2nd gear is a 2.055 to 1
If you have to change any gears, I would put the 2nd gear from the D -model in.  Unfortunately, it requires a whole D-model tranny to do it!
It takes about 20,000 kms for the transmission to fully break-in.

 

At 75,000 kms the second gear started to go away, and by 79,850 kms the engine came out for the 1109 up-grade.  Second gear was still useable, but it would come out of and right back into gear in the most inopportune times. While the tranny was being repaired,(3 forks, shift drum, second and fifth gear) I also have the tranny gears shimmed. It was worth every penny!

I have been using Metzelers MEZ1 190/50/17R rear and 120/70/17R front.
One front tire to every two rear tires. I get about 10-12000 kms out of a rear with the center worn out. Would like to try the Dunlop 207's, but I got a new set of BT-56 of a Zx9r for the price of the rear. They seem to be lighter than the Metzelers. Felt like there was a improvement in straight line acceleration. It handles much better to, but that's to the fact that I never had to put my feet down anymore when I came to a stop!
If money was no object, would purchase a set of carbon wheels. 3.5 lbs front and 4.5 lbs for rear. Costs $4500 U.S. a pair. That's about 10 lbs out of the front and probably close to 20 lbs out of the rear. Maybe in my next life.

 

 

 

 

Well instead of a turbo upgrade, I went for the Dymag hollow DOT die-cast magnesium wheels.  Rear is 6.25 inch wide and the front is stock -3.5 inch wide.  It saved 9 lbs off of the rear (already had remove almost 2 pounds with the aluminum sprocket) and 5 lbs off the front. This required a re-think on what tires to mount.  So I tried a Pirelli Corsa 200/50/17 rear.  With two very minor mods, it fit like Kawasaki had planned this back in 1990.  The tire is 209 mm across and 24.8 inches tall. When leaned allot more throttle can be applied compared to before.

 

 

 

Stock setup is a 17 tooth front sprocket and 45 tooth rear sprocket with a 532 110 link chain. I was not enjoying all the weather reporting that I was doing.
I found out unofficially that Kawasaki was thinking of a top speed kit for the Zx-11. It was a new chain with a 42 tooth sprocket. Interesting! It never was offered to the public. I guess at the time 176 mph was fast enough.
I ended up buying a Specialty Sprockets Aluminum 42 tooth that also save 1 lbs. 10 oz.. and a Tsubaki 530 Sigma 108 link chain at 34,000 kms. Front wheel is much more controllable, even with the 7 percent taller gearing.
This bike will stand on its rear light with out pulling on the bars and just nailing the throttle at 2900 rpm. ( 1st gear ). It would be useless with 45 tooth and unrideable with a 47 tooth or greater.

 

After the engine upgrade and wheels installed, I decided to use a 41 tooth rear at/near sea level and a 42 tooth at 3000 and above.  With the 41 tooth on board the bikes theoretically redline in six gear at 204 mph.  With the 42 tooth it would be 198 something mph.  This bike has seen the back end of a topped out Hayabusa.  You can make your own conclusions.

 

 

First set of rotors were warn out at 43,000 kms. I replaced them with stock set.( got a good deal on them ) The front brake lines were up graded to steel braided and I have tried all the pads. I came to the conclusion that the stock sintered pads are the best. Having said that, I hear that the new EBC 101 Sintered pads are very good. Of course the sintered pads eat rotors.
Rear I haven't changed the lines as the brake is powerful enough. I ended up with SBS pads in the rear as they seem to apply more predictably. Change the fluids once a year and the best tool for the job is a Mighty-Vac brake bleeder. Use new brake fluid from an unopened container.

Note: If you up grade your wheels to lighter ones, then the power of the brakes increases greatly.

 

Well the EBC 101 Sintered pads are great.  And they actually don't eat the rotors as fast as I thought they would.  Still running stock brake components, except the rear caliper had to be changed to the D-model to work with the wheel.  Lost a pound for all the trouble.

Front: After 30,000 kms, the front springs are toast. I replaced mine with Progressive Springs. I use 10W synthetic fork oil and replace it every 15,000 kms.
Fork seals go on average one every 1 1/2 years. The fuel tank is pretty darn dent resistant though!
I use 1 1/4 inch sag in the front. Rebound is set at 3rd click. With rebound set at the 4th click, I once experienced a wicked tankslapper at 150 kms no less.
After 68,500 kms, I took the forks apart and the internals were in perfect shape. But I noticed that the 4th click in the rebound had no hole drilled(Stock). The first hole measures .060" 2nd - .045" 3rd - .020" 4th - .000". I didn't need more rebound than # 3 click. But what about less? So I put the dampening rod assembly in a drill vise, and picked a .034" drill size. Now the #4 click will be somewhere between # 2 click and # 3 click. As it turns out, it is a very useful setting. I also replaced the seals with Pro-Moly Leak Proof seals. But they are not that leak proof. I went back to stock seals and that's that. I refilled with Bel-Ray 10 weight fork oil and put the level to 150 mm from top. (454 ml each leg).

Rear: After 68,500 kms, the rear is still as good as ever. I have set the sag at 1 inch and rebound at the 2nd notch. I weigh 220 lbs. with gear on and it seems set up prefect for me.

If you have a weave or bar shake at or around 80 kph. chances are your Steering Stem bearings are loose. Lubricate the bearings as there isn't much lube on them from the factory. This will also move them in the bore and change the contact point of the bearings. I still have the original bearings installed.
The bar ends weight a ton. Replacing them with aluminum will remove 15 ounces. There is no noticeable increase in vibration.

Modifications:

Modifications:
Battery Replaced with 9 AH battery removed 3.5 lbs
If you buy a new battery, make sure that it has been treated with "Sulfate Stop". What this stuff does is allow you to run it dry, or totally discharge the battery and it will return to 99-100% new after recharging the battery. It protects the plates from sulfating which is what kills batteries. For those batteries that are not protected, you can buy the product for Kleen-Flo and it is called amazingly enough "Battery Treatment" It a little 4 oz. bottle with a clear blue solution. This stuff works great!

Fuel warning relay No more flashing fuel lights. removes 3 ozs.
Fuel warning lights Replace stock 3 watt bulbs with 2 watt bulbs
Horns Remove one all together and relocated the other below the oil cooler.( original pre-production location ) removed 15 ozs.
Tachometer There is a 4 % error in my tach (rev limiter cuts in at 11,950)
Speedometer There is a 0 to 5 % error in my speedo, depending on the temperature, ( colder reads lower, hotter reads higher ) keep the cable well lubed including the speedo head where the cable goes in. This makes it read more accurate. And yes I know it isn't electrical.

Part 2

After the 1109 kit upgrade the 9 amp battery no longer had reliable starting power to turn the 12.2 compression.  I opted for a Odyssey gel cell that was mounted sideways.  The other penalty was a 3.5 lb increase in weight. The storage capacity of this battery is amazing.  After 8 weeks of sitting in the bike, I checked it with a volt meter. It had 12.95 volts at the terminals in 40 degree F.  Hit the starter and it springs to life.  After 89,000 kms every electrical component is still original except for the occasional light bulb and the battery.

I reside in Surrey, British Columbia, Canada. There are some of the nicest roads in the world here. My personal best quarter is 10.46 at 136 mph uncorrected (98%) and at sea level fighting the weather reporting. The bike has seen sixth gear and 11,000 plus rpm's on the clock.
It gets on average 17 kms per litre (40 mpg ) and as high as 23 kpl (54 mpg ) at 120 on the highways. Lowest was 15 kpl.(35 mpg ) I also have quite a few 800 - 1100 kms one day trips under my belt.

 

Since the 1109cc kit upgrade, the bike is just wonderful all round sport tourer with a very large emphasize on the sport.  The wheel upgrade makes the bike feel more like a 750's or 900's(of yester years).    The engine is legendary. Even more so now.  One a dyno at 3000 ASL, It pulled a corrected 158 hp.  At sea level in a high state of tune with the right fuel it would be in the 160's.  With the cams set up for top end power, high 160's to a 170 would not be out of the question.  I failed to get the bike down a quarter mile track in 1999. This was a work and weather issue. I would think that it would be in the low 10's with a high 9 sitting in the wings. Speed should be 140 plus. Time will tell. The bike still see's sixth gear and 11,000 plus rpms.  Just quicker and higher. The mileage has suffered a little, but this is largely due to the lack of straight interstate kind of riding.   

I hope that everyone who has read this will have learned something or has found an idea that they wish to use to further improve their enjoyment of their ride. This information can easily be used on any other bike. Any bike, but especially the Zx-11 / ZZR-1100 has to be treated with much respect as it surely does not respect you!