davefrombc

Shoulda looked at a picture o your axle before I posted LOL.... I see your quad has an IRS rather than a solid axle like my old Honda. I just watched a video on removing the axle and see it is just slid into the differential housing so it is the hub that keeps everything in place. It likely is the right one and play should be pretty much gone with everything buttoned up. My only experience with an axle similar to that is the drive axles on my car .. They are held in the same way , and there is a little play withing the cv joint on them that I originally thought was a problem but it is a function of the joints .

Is it possible the axle has a short spline one one end and a long on the other and it has been installed the wrong way around?.. There should be no end play in the axle if it is installed correctly and the proper axle for the installation .

Today is our day to celebrate being the best nation on Earth.. Canada Day .. July 1st ... to those celebrating our countries birthdays ( Canada and the U.S.of A. ) this weekend, I say have a very Happy and Safe holiday weekend. To those that will not be online Tuesday.. Have a very Happy and Safe July 4th.

My first guess would be a faulty accelerator pump (hole in diaphragm ?) but also look for an air leak, or lean run from a partially plugged jet. Try adjusting the air bleed screw. It may have turned out on its own.

Note there is a connection from the starter relay to the CDI box to deliver power from the relay to the CDI when the starter is running . When the starter is not running the CDI gets its power from the ignition circuit.

Since it you have replaced everything in the spark circuit , it is time to start checking again to make sure none of the wires and connections are broken or corroded. Here is the wiring diagram for your quad.

The stator and the pick up coil or just the stator ? The stator and pickup coil together produce the power and pulse to fire the CDI and coil. The stator produces the electricity to run the machine and all its components and accessories. The pickup coil creates a pulse to trigger the CDI box at the proper point in the cycle to fire the spark coil.

The clear tube was used to show the fuel level in the float bowl. it is not part of the installation .. To use it , the screw would be backed out to allow fuel to fill the hose .. Since liquids will seek an equilibrium level, it is an easy way to see just where the fuel level in the float bowl is when chasing carb problems . That screw would normally shut off fuel to the line except when draining the float bowl or using that trick to see the level the floats are actually holding in the carb... It could be low causing fuel problems, or with the fuel tank above the carb, it could show that the float needle valve is leaking allowing the catb to flood and leak. If the needle valve is in tight and fuel is still leaking from that line , I would say the the needle seat is damaged and allowing the leak. With that screwed in all the way there should be no fuel getting into that line .

I searched on your carb and it appears it is a float bowl drain hose (if I got the right carb in my search) there should be a screw to close the drain. If it is right , close the screw. Looks like it is there to easily drain any water out of the carb if you get some contaminated gas. https://www.google.ca/search?q=bayou+300++carb+adjustment&tbm=isch&tbo=u&source=univ&sa=X&ved=0ahUKEwjskrywpNrUAhUH32MKHeiKARYQsAQIXQ&biw=1696&bih=1015#imgrc=UhZ7gJl4FLWlWM:

Did you check to see if the driven clutch is free to open up?.. If it is sticking it can prevent the drive clutch from closing all the way. You can get tachs that work on a optical system. Put a reflective mark on a rotating pulley , clutch or whatever and the hand held optical tach reads the reflections as pulses to calculate rpm Search on "hand held optical tachometer" or "laser photo tachometer"

I searched on the revving problem and found suggestions that the slide could be in backward or the crank seals could be leaking several suggested the crank seals were the most likely culprits. Here's where I found the discussion https://atvconnection.com/forums/suzuki/348745-1991-lt250r-reving-its-own.html

If the motor will rev up ok , I'd suggest blocking the quad up with back wheels off the ground.. Make sure it can't fall off the blocking and can't move. With the cover off the CVT so you can see what's happening , rev the motor up and watch the clutches.. The motor clutch should close until the belt is at the top of the groove and the driven should open until the belt is almost down to the bottom. . Without a load on the tires , it may not open all the way since opening and closing of the clutches is determined by the load on the system as well l as the RPM. The motor should rev well over 3500... should go to around 6000 - 8000. Have you also checked to be sure you don't have a brake dragging ? The tires should turn fairly easily when off the ground. There will be some resistance from the drive train , but it should not be difficult to turn the tires

My guesses ....Bad ground, neutral switch or relay, wonky ignition switch.

The symptoms you describe all point to fuel problems , and a stcking float needle valve is the most likely culprit .

That sounds like the float or needle valve in the float bowl is sticking and not letting the fuel into the float bowl. . You might als try disconecting the fuel line and asee if fuel flows freely from it .. There could be an obstruction in the line or fuel petcock.

A lot more information is needed before anyone can begin to try to help you . There is a download of the service manual for the 400ex in the forum's archives .. Go to Browse at the top then click downloads and click through to the Honda section service manuals. If the motor turns over , check the spark plug for spark and the carb is getting fuel. If it doesn't turn over, then check battery, fuses and neutral switch for starters.. Then use the service manual as a guide to check other components .

I wouldn't think they'd interfere with the spark.. They are part of the charging circuit.. The pickup coil uses voltage produced in the stator to send a pulse to the CDI at the proper point in the cycle to fire the spark plug. The stator is producing a constant 3 phase ac voltage the regulator / rectifier changes to the 12v DC for the charging system .

Here is the link to download the yfm 250xl 1998 service manual .. Your 2000 250cc motor most likely has the same stator and pickup coil.

Did you check the pickup coil that works with the stator to produce the pulses necessary for the spark?. .The stator not only produces the voltage pulse the pickup coil uses for the spark circuit , but also the voltage for charging the battery. The stator and /or the pickup could be bad and still produce some voltage.

Sounds to me like either there is still some blockage in the fuel passages of the carb making it run lean without the choke on, or possibly the throttle slide needle is set wrong .. This video on rebuilding the carb might help:

Check that the quad is in neutral for certain. From that point it is a case of trouble shooting the wiring . You can download the service manual for that quad here: Page 327 has the wiring diagram for the starting system

I also came up with Bayou 185 searching on that info. Lots of hits on sites offering parts for it.

I looked at the title of the request and realized it was actually an mz 100 you needed info on ...Searching on that didn't bring much of help up. Seems it was a Chinese quad imported into Europe by a German company .. Searching on it brought up a forum where someone stated it was a licensed copy of a Jehm Blazer. Searching on that, I found there are some US dealers in them and parts.. You may be able to get more info from one of them. I hope this helps and you're able to get the little mz running .

Searching on mx 100 ATV and muz mx100 ATV brings up references to Yamaha mx100.. That is quite possibly the quad you have.. Try searching on that and see if it is the same quad you're working on .

Then all is working as it should.. The fan won't cut off unless the engine cools below the temperature sensor switch turn on point and the switch opens.. You could just wire in a switch to disconnect the fan switch. I wouldn't recommend it though. Kawasaki had a reason to set it up that way , and if you wire in a switch to disconnect the fan switch it is too easy to forget to turn it back on when you want to run the quad and end up overheating it. You could wire in a master disconnect between the battery and the wire to the ignition to disconnect all power so nothing will be powered with it off; but as long as your battery is good it won't hurt anything to let the fan run until the engine cools to the point the fan switch opens and the fan turns off on its own... It easily could take a half hour or more on a hot day. but the fan motor shouldn't draw a lot of current and deplete the battery. I would be inclined to just wire in a battery disconnect. Not only does it ensure there are no powered circuits when it is opened, but it also slows down a thief who just tries to hotwire the ignition . It won't stop determined thieves who knows to look for a disconnect , but it does slow them down and could be just the delay needed to make them look elsewhere.