I have a 2003 Redcat MPX 150 that I acquired and have several questions as to what is what on this thing. I am new to the ATV world and want to iron a few things out here so I don't hurt anything. The first question I have is what engine oil does everyone run? The placard on the front end of this thing says 5W30. I live in Ohio. This will primarily be ran in the spring and summer on blacktop at the drag strip as a pit bike and occasionally around the yard at home but very rarely if at all on any trails. This has a Auto trans with Reverse. Does it take fluid at all? The rest of my questions are in the photos below. Below are several photos along with red arrows pointing at each item in question. Any help on this matter would be greatly appreciated. Thanks in advance!!
What is this black hose


What is this Tube? You can hear engine noise coming from it. If you stick your finger over it the engine sound becomes very quiet


What is this black canister? There are 2 empty ports on it. Is the smaller hose that is hooked up to it supposed to hook up to it? If not then where should it go. This thing no longer has the air box on it. The previous owner has a 1.75x4" foam Uni air filter on it.


What and where does this hose go? It's just laying here


Whats this black hose for coming off the side of the carb?


Whats this box with the fins? My headlights dont work and the bulbs look alright. They removed the tail light and its just the sockets tied up in the rear. But I dont believe that has anything to do with the headlights not working.

 

The Black hose is a vent from the fan housing.. it blows air on the carb..

The Tube is part of the smog items and a vent for the valve cover.

The Black Canister is more smog crap.. Usually that smaller hose goes from the side of the carb to the intake manifold.

The hose laying there looks like another vent for the head.. its ok where it is..

The black hose coming off the side of the carb is a overflow vent hose..

A rectifier.

 

OK on the small hose that you say ussually goes from intake to carb. I cant find an empty port anywhere for it to go. Any suggestions or ideas? Also on that smog tube what should I do there? leave it open? Where is the valve cover located that I could run a hose from it to the valve cover? Thanks for all the help on the above.

 

In pic 5.. does that small hose connected to the side of the carb go to the intake manifold? if so plug the one on the other side and toss it and the cannister. Unless your worried about being smog legal.

If it was me I would toss the xtra stuff and get it running.

The valve cover is in pic 2..For the tubes on the valve cover I would connect hose's to them and vent them under the plastic somewhere..

 

OK well I appreciate everything on the photos I posted. This thing has a 1 3/4" X 4" Uni foam air filter. The thing fires right up. The idle and part throttle is great. But WOT or anything after part throttle and it goes flat and then dies if you don't let off the gas. We have tried everything from a 1/4 turn to 5 turns out on the A/F screw. At 5 turns out the screw losen'd itself due to the vibration. Here's the thing though. If you wrap your hand around the filter and restrict the air flow it revs to the moon. But the minute you let go of the filter it will go flat and have no power and will die if you dont return back to idle. Any help would be great because I am lost now as to what to do. This thing doesn't have a choke either.

 

Winding the slow running jet out won't affect the running at over half throttle as the engine is on the main jet at that speed. On most CD carbs you can lift the needle in the CD piston to give more fuel on the main jet.

 

As long as there are no vacuum leaks around the intake manifold(you can find leaks by spraying carb cleaner around the manifold while its running)Id say your carb needs to be taken apart and cleaned..

I missed this.. motor oil.. use your favorite 10w-40 motor oil.. gear oil? yes I d assume there is gear oil in the gear box. 80wt-90 will work..

 

We pulled this thing apart and the needle doesnt appear to be adjustable unless were issing something. This thing doesnt have a fuel filter or a choke either.

 

Your choke is in pic 4.. to the right of the arrow... its electric..

 

Ok thank you. I pulled the carb back apart and everything g is clean and nothing clogged. The main jet is a 110. Not sure what I need to step up to in order to get this thi g richened up a little so it won't be lean with this new air filter. Any ideas??? Also do these Chinese quads use the same jets as a Honda or Yamaha etc.... Something I can get at my local motorsports dealer or will I have to order??