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  ZRX1100 / ZRX1200 FAQ

This Frequently Asked Questions page was originally written by Walt255
and Revised February 27, 2004, by chuckc

Some of the info on this page is no longer valid, but it will be updated soon.
Please let chuckc know if you find any problems.
Your input will improve this document.


1 WHAT IS THIS FAQ DOCUMENT ABOUT?
 

2 OVERVIEW OF THE ZRX1100/1200
2.1 Deep in history:
2.2 Shop manual:
2.3 Your new ZRX:
2.4 Recalls:
2.5 Usage:
 

3 SPECIFICATIONS
 

4 ENGINE
4.1 Air filters:
4.2 Cams:
4.3 Oil:
4.4 Reed blocking plates:
4.5 Exhaust systems, slip-ons, bolt-ons:
4.6 Jetting:
4.7 Spark Plugs:
 

5 ELECTRICAL
5.1 Horn relocation:
5.2 Engine temperature warning light:
5.3 Electric clothing:
 

6 SUSPENSION AND HANDLING
6.1 Understanding how steering works:
6.2 Shocks:
6.3 Modifications:
6.4 Settings:
6.5 Rear Shocks:
6.6 Steering damper:
6.7 Fork boots/protectors:
6.8 Brands of tires:
6.9 New tires:
6.10 Understanding slip angles:
 

7 CHASSIS
7.1 Brakes:
7.2 Mirrors:
7.3 Chains:
7.4 Rear axle eccentric chain adjuster:
7.5 Sprockets:
7.6 Alignment basics:
 

8 COMFORT
8.1 Windshields:
8.2 Seats:
8.3 Handlebars:
 

9 MAINTENANCE PROCEDURES
9.1 Valve adjustment:
9.2 Rear axle nut:
9.3 Some maintenance guidelines:
 

10 ODDS AND ENDS
10.1 Touch-up paint:
10.2 Luggage:
10.3 Spare keys:

*****

1 What is this FAQ about?

This FAQ is inspired from information that has appeared on the message board. It is not intended to replace the existing sections of this ZRXOA site (such as specifications, road tests, vendors, and part numbers) since they are already so well done. Rather, it is intended to structure some answers to questions specific to the ZRX that are not covered in the other sections.

The purpose of this FAQ is to help visitors find answers more quickly than by reviewing the whole message board. References to other sites are made where topics of general interest are well covered. The message board remains an excellent means of finding any additional information on any topic.
 
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2 Overview of the ZRX1100/1200

2.1 ZRX history:
Interesting info and pictures on the lineage of the ZRX are available at http://www.ixpres.com/jvanslyke/kawi/kawi.html

2.2 Shop manual:
Kawasaki's shop manual (part no. 99924-1196-02) is reasonably priced at around 40 $(US) or (US) $(CAN), and covers all ZRX1100's produced from 1996 to 1999. It is also applicable to 2000 and with exception of the larger 1200 motor, to the 2001 ZRX as well . Neither Haynes nor Clymer have a manual for the ZRX1100/1200.

2.3 Your new ZRX:
Following the break-in procedure in the owner's handbook will start your ZRX off right. There is also a case for taking it easy with a new bike until you are sure everything works as it should and until you get a good feel for it.

2.4 Recalls:
There have been two recalls of ZRX1200's. Find details of recalls on the ZRXOA message board.

Members have mentioned these items to watch out for:

     1.Low coolant level when delivered or air in cooling system
2. Engine ticking when cold or idling
3. Headlight adjustment off
4. Front brake squeal
5. Early scoring of cams
6. Exhaust paint peeling
7. Carb mixture screw adjustment off from factory
8. Leaky fork seals
9. Defective petcock or kinked vacuum hose (see below)
10. Rear axle seal defective        
11. Chaffing of wiring harness with extended mileage and vibration
       
12. Loose engine mounting bolts
       
13. Loose tail section bolts

 Some things to know about that give the ZRX "character" are :

1. The sidestand is ready to go! The ZRX will roll off its sidestand more easily than expected. Park facing upslope when possible and leave her in first gear. Modifications have included grinding of the forward stop & bending the stand leg to minimize this tendency.

2. Who is that behind me? The stock mirrors leave a lot to the imagination. Riding so fast that it doesn't matter what is behind you is tempting but not a solution. A tight jacket helps. Arm bands (reflective is good) will help if you have a bulky synthetic jacket by keeping the sleeve snug to your arm. Most leg bands made for cyclists will work for this purpose. Some owners have replaced, modified or extended the mirrors (see chassis section below).

3. How fast are we going? Speedo accuracy is around 10 % optimistic. For instance, it reads 66 when you are going 60.

4. Hard starting? Don't touch the throttle when starting cold or hot. Find the right dose of choke for your situation.

5. Clunky shifting? This is probably due to the clutch not being worn in enough. It takes a little longer than the engine break-in period but ends up smoothing out nicely. Your choice of oil might be a factor. Synthetic oil will provide easier shifting. Pre-loading of the shifter will help greatly.

6. Adjusting rear spring preload with the tool is not knuckle friendly. One member reports that a BOA CONSTRICTOR strap wrench (the smaller size) as sold in most hardware outlets makes an easier job of adjusting rear preload.

7. Strange noises? Fuel tank “sighing”? When stopped the fuel tank vents excessive pressure, which is evidenced by a hissing sound. This is normal.

8. Engine stops for no apparent reason? If turning the petcock to “PRI” fixes the problem, look for a kinked vacuum hose going to the petcock.

2.5 Usage:
The ZRX is probably the most competently versatile bike on the market. It doesn't really fit any one of the usual street categories (sport, touring, cruiser, standard) but does many things very well. Owners use and modify them for a broad range of purposes from dragracing, roadracing, canyon carving to two-up touring.

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3 Specifications
Click for brochure specifications.
 
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4 Engine

4.1 Air Filters:
Some members have installed individual filters (pods). Air box removal is a royal pain and requires some other mods like reed blocking plates, and rejetting is recommended. Some sensitivity to strong crosswinds which has been traced to the carburator overflow tubes placement. The problem has been eliminated by either routing the tubes so they are shielded by the engine or removing them all together. Some members have opted to install a K&N replacement filter and retain the airbox. There is considerable debate over the superiority of pod filters or the airbox. In either case, when a less restrictive filter setup is installed, rejetting is recommended. Guidance in rejetting is usually provided by the jet kit manufacturer but a wealth of owner information can be found in the Mods section as well as in the threads. Some owners like using Marvel Mystery Oil for the K&N style filters.

4.2 Cams:
ZX-11 cams fit the ZRX and provide 1mm more lift. ZX-11 D cams are popular and available used from the dragracing fraternity. Muzzys , also offers replacement cams. Members have experimented with a variety of Kawasaki and aftermarket cams with varied profiles and specificaitons. Some decrease in low end torque and drivability is usually sacrificed to obtain more top end power.

4.3 Oil:
ZRXers have a keen interest in using the right oils. Synthetic versus conventional oil is a popular discussion. The difference between the two is blurred since some petroleum-based oils are so full of additives that they could be considered as partially synthetic. Some synthetic oils may have a conventional carrier. Mixing synthetics with conventional oils is OK. After putting approximately 2000 miles on, the switch to synthetic is highly recommended by the membership of the ZRXOA.

Synthetic oil offers higher viscosity stability, reduced oxidation, reduced wear, reduced loss of oil through evaporation, reduced engine temperatures, lower oil consumption, lower engine deposits, and better mileage. Additives used to widen the temperature range of conventional oils also reduce wear resistance. This is why synthetic oil outperforms conventional oil at a given multigrade application. Some sources say to avoid synthetics until after the break-in period. Check your owners manual for the viscosity application to use under different conditions.

Another side of the great oil debate is use of automotive oils in motorcycles. Some members have reported using automotive or diesel oils without any problems. Motorcycles may operate under more stress than automobiles and call for extra protection. According to some sources, synthetics have been linked to grabby clutches and Energy Conserving conventional auto oils (API SJ service classification) have been linked to slipping clutches or malfunction of the starter mechanism (not mechanical failure).

Motorcycle-specific blends are formulated to keep wet clutches and gearboxes happy. A motorcycle-specific synthetic oil is best but also the most expensive. A motorcycle-specific conventional oil is a little less expensive but entirely suitable for normal operation. Motorcycle oil manufacturers now have their own oil specifications, JASO-MA (the best) and JASO-MB (the good).

There is no one oil that is the best to use. There are many choices, but the best advice is to pick the top quality oil you prefer, then keep it (and the oil filter) changed every 3000 miles; sooner if you ride extremely hard or in harsh conditions.

Oil change intervals should be the same regardless of oil type because contamination by dirt, water or gas occurs. It is incorrect to use the color of the oil as the only criterion in determining when to drain the oil.

4.4 Reed blocking plates:
Reed blocking plates permit the removal of some pollution control hardware under the tank. Improved drivability and idling have been reported after this mod. Naturally any changes to the pollution control system is illegal per Federal Law. The current ZX9-R sales brochure has a good picture of Kawa's system which dates back at least to the GPZ 900 Ninja of the 80's. The system allows fresh air into the exhaust port to complete combustion of exhaust gases. In addition to blocking plates there are a variety of DIY methods of blocking the reed valves, the simplest being to use a short piece of plastic tube between the hoses.

4.5 Exhaust systems, slip-ons, bolt-ons:
The most popular topic on the message board. Exhaust systems and slip-ons have become a major cottage industry. In some areas, exhaust system laws are lax and in some areas are oppressive. The only way to really judge the sound of a system is to listen to it on a ZRX - one of the many good reasons to go to some of the ZRXOA events.

There are a great many exhaust systems available for the ZRX1100/1200, either in slip-on form or full systems: Vortex (Holeshot Performance), Two Bros., Beet, D&D, Muzzy, Kerker, Arete, ART, Bito, Borla, Devil, Harris, Hurric, Jardine, JB Power, Laser, Moriyama, Moriwaki, Quill, Remus, Shark, Akrapovic, M4, Stainetune, Sudco, Hindle... all make systems and/or cans.

For the DIY members interested in changing the sound of their ZRX or saving a few dollars, drilling or modification of the baffles in the stock muffler is an option.

4.6 Jetting:
Exhaust system, valve train, or air intake modifications usually lead to rejetting the carbs for optimum performance of the engine. The air-gas mixture at full throttle is determined by the main jets hence the need to change the rate of gas supply if the air supply rate is changed. Jet kits are intended for professional mechanics or advanced amateurs who are willing to spend many hours fiddling to get the gas-air mixture optimized for a given set of modifications (cams, exhaust system, carbs, air filters, etc.) Dynojet, Holeshot, Factory Pro and others sell jet kits for the ZRX. There is considerable debate on which of these brands are best. Final results would seem to depend more on the skill of the tuner than the brand of kit.

If you remove the idle screw plugs, the screw settings may be disturbed in the process. Unless you have reason for a special setting, reset the idle screws to 2.25 to 2.5 turns out.

4.7 Spark Plugs:
The original plugs (NGK CR9EK or ND U27ETR) can be hard to find and expensive if purchased from your Kawasaki dealer. An NGK C9EK plug can be substituted. The R designates that the plug has a radio interference suppresser which is not necessary on a bike (unless you have a radio on it). Check out the info on NGK plug codes at http://www.parlorcity.com/pkahlert/zephyr/ngk.htm

4.8 Cooling system:
After any work on the cooling system, thorough air bleeding should be done as explained in the maintenance section below. Hose clamps should be tight and after a bit of operation, checked for leaks.

Some members remove the radiator side shrouds for better looks and weight savings. It is not clear what these shrouds are for besides supporting the radiator (i.e. heat shield, hot air diversion, etc. ). Removal of the radiator shrouds leaves the bottom of the radiator unsupported. Some members say that the remaining top mount and the radiator hoses provide sufficient support but some others prefer to add a brace. Some cracking of the upper radiator support tabs have been reported by some members, so radiator mounting changes should be approached with caution. The horns obviously have to be relocated.

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5 Electrical

5.1 Horn relocation:
Horn relocation has been done by some members to get them out of sight. Some relocate them to the engine mounts behind the exhaust pipes in front of the engine or inside the fairing. Several members make horn relocation kits.

5.2 Engine temperature warning light:
The temperature warning light may come on without evidence of an overheating problem. It is suggested that coolant level be checked when new and periodically thereafter. Also, there may be air trapped in the cooling system which could cause the temperature warning light to go on due to it's sensor location. Refer to bleeding the cooling system in the maintenance section below. FYI the thermostat opens at 80-84 C and is fully open at 95 C. The radiator fan switch goes on beyond 95 to 101 C. The temperature warning light goes on beyond 112 to 118 C and off again at between 108 to 111 C. If the light comes on while the fan is off, one of the switches is defective.

5.3 Electric clothing:
The ZRX has a decent generator at around 400 watts. This is enough for electric clothing for rider and passenger. Widder or Gerbings provide a lot of useful information on this subject at their web sites. Heated gloves are a logical and effective measure for cool weather riding on the ZRX because of the lack of hand protection afforded by the stock fairing.

5.4 Accessory hook-up:
A 10 amp accessory connector can be found in the tail section behind the tool compartment. The tail box must be removed to access it.
 
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6 Suspension and handling

6.1 Understanding how steering works:
James Davis offers an informative article titled COUNTERSTEERING that deals with many aspects relating to stability http://www.msgroup.org/DISCUSS.asp (currently #48 in the list)

6.2 Shocks:
James Davis offers an excellent explanation of the functioning of shock absorbers http://www.msgroup.org/DISCUSS.asp (currently #5 on the list).  Modification of the front forks and rear shocks for better handling are popular. Works, Progressive, Race Tech and Ohelins, to name a few, offer replacement springs, valves and complete replacement components.

6.3 Modifications:
It may be fun to mess around with motorcycles but results don't often measure up to expectations. Take the time to get as much information as you can before making changes. Where possible, ride a ZRX that has the modification you are contemplating.

6.4 Settings:
The suspension setup page provides most of the answers on using the adjustments available on the ZRX. The ZRX offers many adjustments which are worth making to get the best handling under different conditions. See the SUSPENSION SETUP PAGE for suggestions on suspension setup.

Front and rear preload should be changed when carrying a passenger and then changed back when riding solo again. Special tools are available for adjusting the front (Snapon #YA8980 and others). Convenient adjusters are available that can be installed on the front which allow the adjustments to be made without tools. See kyleusa.com for an example.

6.5 Rear Shocks:
The rear shocks have a chrome collar under the preload adjuster that seems to allow for two ranges of preload settings. This collar carries the two bosses against which the notched preload adjuster slides. The collar in turn is held by two bosses on the shock body. There are two sets of slots in the collar that would indicate the possibility of rotating the collar 90° to increase the range of the five preload settings.

Rear preload adjustment is hard on the knuckles with the tool provided. Use a firm, steady pressure when turning the adjusters. Make sure your knuckles won't slam into something if the wrench slips. A better technique or tool would be welcome.

6.6 Steering damper:
The necessity of one is not obvious with stock steering components and geometry. Riding style and ability are also factors. A steering damper could be good insurance if you make some suspension mods that quicken the steering (such as turning the chain adjustment eccentrics to raise the rear end) and/or raising the fork tubes. Dampers seem to be on most project bikes, so you can get more info from suppliers featured at this site.

6.7 Fork boots/protectors:
It is reported that Triumph fork protectors fit well. The Triumph part number is A9641010-N/T. Other protectors are available with aftermarket fork braces, some of which are made by ZRXOA members.

6.8 Brands of tires:
Brand choice is a matter of personal preference and a broad topic of discussion on the ZRXOA message board. Manufacturer's sites are helpful and provide general technical charts and info as well as info specific to their own tires.

6.9 New tires:
As most of us have heard, the mold release stuff that is on new tires must be worn off a tire before going full tilt. A new tire isn't to be trusted until it is scuffed up a little. It is also important that the tire be seated properly on the rim before carving up the canyon. Allow around a hundred miles of riding (or at least a day) for the tire to grow and stick to the rim before getting too aggressive in the twisties.

6.10 Understanding slip angles & tire deformation:
James Davis offers more information at http://www.msgroup.org/DISCUSS.asp (currently #76 in the list)

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7 Chassis

7.1 Brakes:
Brake squeal is a common occurrence on the ZRX and is classified as an annoyance. Most occurrences of serious brake squeal seem to happen when the outside temperature drops below 50 degrees (F). No solution has been found that eliminates the problem 100% of the time.

7.2 Mirrors:
Accessory mirrors such as Napoleon mirrors have been recommended by some members. Bar end mirrors from Hindsight are also a solution to seeing what's behind. Stock mirrors have 10mm x 1.25 pitch threads, both right handed.

Mirror extensions are built by some ZRXOA members. Some members have modified their stock mirrors by heating, bending, and repainting the stems.

7.3 Chains:
DID provides an FAQ on chains at http://www.didchain.com/question.html. The stock chain has 110 links. Kawasaki recommends the master link pins be mushroomed to retain the side plate. Some members have reported success using a locking clip “safed” with a dab of silicone.

7.4 Rear axle eccentric chain adjuster:
Marks are provided on each eccentric to maintain wheel alignment. Marks on the swingarm may not provide perfect wheel alignment so a more precise adjustment using the "string method" can be performed. It is recommended that the axle and axle nut be removed, cleaned and coated with anti-seize compound.

When adjusting chain slack it is not necessary to loosen the axle nut once you are sure of wheel alignment. Just loosen the eccentric clamp pinch bolts. Some members have reported difficulty in loosening the pinch bolts when adjusting chain slack. The torque spec for the pinch bolts is 29 ft-lbs.

Some members have rotated the eccentrics 180 degrees which effectively raises the rear of the bike. This change quickens the steering somewhat and reduces squat under hard acceleration. The chain slack adjustment procedure would not be affected, however the markings that Kawasaki has provided for wheel alignment only work in the stock position. A string alignment must be performed. Once the alignment is made and the axle nut tightened, new reference marks can then be made on the swingarm to facilitate future chain adjustment. Some chainguard mods might be required if the chain rubs on something.

7.5 Sprockets:
Some members go down to a 16T engine sprocket from the stock 17T. The ZRX sprocket has a boss on it that sets it apart from a ZX-11 sprocket. To fit a ZX-11 sprocket, a 3mm or 1/8inch washer (ID=30mm, OD=40mm) must be added behind the retaining nut. Larger rear sprockets of 47 teeth and up have become popular with bikes equipped with ZX-11 cams. Steel and aluminum sprockets are available. Steel is preferred for longevity and aluminum is preferred for light weight and improved rear wheel horsepower readings on the dyno.

7.6 Alignment basics:
Rob Tuluie has some good articles at http://www.motorcycle.com/mo/mcnuts/chassis.html

7.7 Swing arm stands:
The swing arm lugs have a 10mm x 1.25 metric thread. The use of a quality swing arm stand will ensure the stability of the bike during maintenance procedures or other work.
 
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8 Comfort

8.1 Windshields:
The original fairing seems to give good protection for its size. Givi, Zero Gravity, Lockhart and Targa are all selling replacement windshields . If you find more helmet buffet with a larger windshield try removing the vent insert (held with 2 screws) to let more air get behind the windshield. For even more coverage Slipstreamer also has a universal model (SS28-29.5" wide) that covers the hands and rises to the height of the mirrors. It replaces the whole fairing but mounting it is tricky. Rifle also offers various fairings adaptable to the ZRX.

FYI: Larger windshields can be expected to reflect more engine noise and/or lighting back to the rider. Also, they change the aerodynamics of the bike which means that handling is affected especially at higher speeds. One rider's impressions of a product do not necessarily apply to another rider of different height, proportions, or posture on the bike.

8.2 Seats:
Some owners find the seat uncomfortable. Some don't. Corbin seats are popular among some members but options such as Sargent seats are also mentioned by other members. The Corbin is lower than the original seat but because it is flatter, shorter legged riders may actually find it harder to reach the ground. Corbin seat is considerably heavier than the original seat.

The metal bracket must be taken from the original seat and put on the Corbin. Obtaining another bracket would allow either seat to be quickly installed in case your favorite passenger prefers the other seat. The bracket only is not available from Kawasaki. A simple design for a DIY bracket is available in the How-to section.

8.3 Handlebars:
There are many varieties of replacement handlebars available. Here are some that are available:
AFAM (aluminum)
Holeshot Superbike (similar to the now-discontinued K&N Superbike)
K&N (if you can find any)
OEM bars off of other machines.

8.4 Highway pegs:
Highway pegs can be mounted on Renntec case guards (see VENDOR page) or clamped to the frame tubes. Clamps for frame mounting must be custom or homemade until a product is available from somewhere. The frame tubes are thin walled and larger than usual. Both are not of the same diameter. Moreover, the larger tube is aluminum so great care must be taken to avoid crushing of the frame tubes when installing clamps on the frame.
 
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9 Maintenance procedures

9.1 Some maintenance guidelines:
The best overall source of comprehensive maintenance information is contained in the Kawasaki Shop Manual.

9.2 Rear axle nut:
The rear axle nut can be difficult to remove, possibly because of rust or galling. Galling can occur if the nut is torqued over spec or the threads are dirty. To remove the nut, do not loosen the eccentric pinch bolts. Start by removing the retaining rings on each side. The axle nut is on the muffler side of the bike. Place the hex key in a horizontal position pointing towards the rear and stand on it. In case of difficulty in removing the nut, use a good quality 12mm hex key socket and torque bar. Before installing, the threads should be cleaned and lubricated with a good grade of anti-seize compound. The tools supplied with the bike should be up to the task of tightening to spec. The torque spec of 72 ft-lbs. should not be exceeded.

9.3 Valve adjustment:
Shims from a dealer can be expensive. Some dealers will swap shims with you without your having to buy them outright. Some members recommend buying shims from Discount warehouse (tel 800-448-8611) at 4.50$ each. Be careful when removing the valve cover that the spark plug well gaskets don't fall into the engine.

9.4 Bleeding the cooling system:
After any work on the cooling system, thorough air bleeding should be done.
 
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10 Odds and ends

10.1 Touch-up paint:
See the part number section for Colorrite products. Hobby stores have a good choice of colors for models at a reasonable price. The bottles are small and inexpensive so you might want to mix colors to get a better shade match especially if the paint has faded on your bike. A Q-tip works well for applying to small dings.

10.2 Luggage:
A tank bag is a basic option. A trunk bag too. There seems to be a choice of brands and models that work on the ZRX. Eclipse, Ventura, Renntec and Givi have trunk racks for the ZRX. The upswept muffler and the rear flashers don't leave much room for saddlebags. Corbin offers streamlined hard bags. Givi hard bags are an option as well. The ZRX is rated for a maximum load of 408 pounds. This includes clothed rider and passenger, and full luggage. Soft saddle bags would be preferable for two up touring because they are lighter than hard bags, carry the luggage lower than a trunk bag, and make it easier for the passenger to get on and off. A heat shield might be necessary depending on the saddlebags to be used.

The original exhaust system can be removed and modified to make more room for saddlebags. This can be accomplished by cutting a wedge out of the pipe close the wedged shaped gap and rewelding the pipe. A short muffler-mounting link must be added between the muffler and the footpeg bracket.

10.3 Spare keys:
Key blanks are only available from a dealer. Note that only one side of the key needs to be ground. The other side of the key can be ground for a different Kawasaki motorcycle if necessary.

10.4 Side stand plate:
The small foot of the sidestand will easily dig into pavement. A jar top or other type of disc can be carried and used under the foot whenever the situation warrants. Welding of a 2” diameter washer to the foot helps eliminate this problem.

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