Over the next few days, I'm gonna add a little info. on this type of mini quad. Some of the information will be useful to some of you newcomers that needs a little helping hand. This info. comes from the service manual and my personal experience. Blood, sweat, and tears! I do not take any responsibility for any mechanical failure or bodily harm that comes from any mods that you performed from my advise.

First, I gonna add a list of the basic specs, then I will break down each area on the mini.

2007-2009 Kawasaki KFX50 SPECS.

ENGINE: 4-STROKE, SOHC, 1-CYLINDER
Same engine as a GY6 139QMB 50cc commonly used in scooters.

COOLING SYSTEM: Air Cooled

BORE AND STROKE: 39X 41.4MM

DISPLACEMENT: 49.5CM3

COMPRESSION RATIO: 10.8:1

CARBURETION SYSTEM: Keihin PTE 16MM/ AUTO CHOKE

STARTING SYSTEM: ELECTRIC STARTER/ KICK START

IGNITION: DC FIRED 12V CDI

IGNITION TIMING: 13 DEGREE BTDC @ 2000 RPMS

SPARK PLUG: NGK CR7HSA / Iridium CR7HIX9(performance plug)

VALVE CLEARANCE: .04MM(.0016 IN.) ON THE INTAKE AND EXHAUST(COLD CHECK)

FRONT SPROCKET: 16 TOOTH

REAR SPROCKET: 32 TOOTH

 

First area I would like to cover is the electrical system. Mainly being the CDI. The stock cdi will only allow the engine to run @ 7500 rpms. It moreless cuts out right before it hits its stride. A good +1000 rpms would have done this mini justice.
Now, this electrical system is a 12VDC current system. Meaning, the cdi is powdered by the battery. The cdi needs 12vdc to fire. A AC FIRED CDI WILL NOT WORK! You will only make a molten plastic mess with a AC fired cdi.
There are now a few cdi's on the market that will work with the KFX50/90. I will add them later to a mods list I will make. Stay tuned for more!

 

I would like to add that the chain is a 428 o-ring type. When adding larger tooth sprockets, you do not have to buy a new chain.There is plenty of chain adjustment. Sprockets can be had a certain vendors, but I found a cheap , good made front sprocket that you can add if you can find it. You can run a 17T front sprocket from JT sprockets. Here is the part number that you will need to reference to find it.

JT SPROCKET PART #: JTF 259.17

The rear sprocket is a little more tricky. Certain mini quads rear sprockets will work,but it also depends on the year, so I won't go into detail what mini quads will work. I will say you can get the rear and front sprockets from Rebel Gears. With only a 17T front and a 28T rear sprocket, you should be able to achieve 17-20mph alone without a aftermarket cdi box.

16x13 roller weights is what you want to order when you replace the rollers in your variator. Total stock weight of all the rollers is 39.5 grams. I tend to run ours at 24-32 grams total depending what gear ratio we run and what engine mods were performed. A good starting point would be around 30-34 grams with a stock engine. Now keep in mind, those 16x13 rollers are for GY6 50cc size, so they can be had for cheap off ebay or any scooter shop. I personally like to run NCY rollers as of late. They are cheap and they make good quality products that exceeds other brands like Koso IMO.

 

New here and was wondering if this list was posted somewhere else on the site?

Thanks...

 

Does this mean that I have to have a good charged battery hooked up for it to run even with the pull start (I have seen on here that the ltz-50 and kfx50 are basically the same bike and I have the '06 suzuki model)?

 

I have a KFX 50 - I have located the aftermarket CDI- where can I find the wiring to hook it it up- i found one at monstergy6. If theres a better one or different one, please let me know. new here so thanks for the help