I just completed an Air Filter Mod for a 150cc Quad. Take a moment and check out my pictures of the mod and let me know what you think. Any comment is appreciated whether good or bad. I am looking for ways to improve the mod if possible. Haven't had the chance to take it out and test it, however, when I do, I will post an update.

I had to modify this air filter due to the fact that the original paper air filter rubber, even though it was properly tightened down, did not keep the dust from getting into my carb. Also, I was concerned with the placement of the air filter. Original design required me to dismantle the front-end (i.e.: seat, fuel tank, plastic, etc...) to get to it. After taking the air filter off, I then proceeded to take off the carb and found light dust. Fortunately, I caught this in time and no damage was done.

I went out and purchased the following items:
1-1/2" to 1-1/4" Pipe Reducer Price: $6.45 Found in plumbing section at Home Depot1-1/2" Electrical Conduit Pipe Price: $0.00 Already had, but you can find it at Home DepotTwo (2) 1" Rubber Insulated Clamps Price: $1.25 each ~ Used for pipe supportUNI Air Filter No.: UP-4182AST Price: $16.95

Total Mod Cost: $25.90 plus tax

 

I tell any one that I can that the stock airbox on these Chinese atv's are junk. I put on a clamp on K&N. Works great and gave it a little more power.

 

This quad did not come with a stock air box, just an off-beat style K&N air filter that was clamped directly to the carb. Looks just like a K&N, but obviously it is not. With my mod and the UNI filter, quad now has a lot more low end torque, is faster and will even pop a wheelie going up hill in the driveway whereas before it would not even pull up off the ground.

 

smb05,

Looks like you are pretty handy. You should have good luck with the chinese quad. Mine have been great for about a year now. Kids were out in the snow today and had a blast. One more thing I would highly recommend is a better set of tires. The stock tires are junk. They are very stiff and makes the handling poor. I went from the stock size 18x9.5x8 rear / 19x7x8 front to a 20x9x8 rear/ 20x7x8 front and went with Fox A/T tires. They work awsome in the snow. The stock ones would just dig down and he would get stuck alot. The handling is way better. He loves it now.

 

toomanytoys,

Thanks, the tires will be one of my next to do's. The tire size is what I was not sure of. Are those Fox A/T tires a good brand to go with? Haven't looked too much into tires yet . We mainly trail ride and don't have to worry about snow that much.

Next, I am also going to tackle making a rear rack for this thing. I'm going to try and design the rack for under thirty dollars hopefully. Trying to keep cost down as much as possible. Bought this quad because it was fairly inexpensive and do not want to put a lot of money into it. The more money I dump into it I should have just bought a Japanese Quad.

This little quad keeps me busy when I run out of other things to work on. What is cool, is that a person can modify these quads due to the fact that they have some design flaws that a person can try and improve on.

Thanks again for the tire info.

SB

 

I think the Fox A/T tires are a great tire for a kids atv. They work really in just about any situation. I bought them from Dennis Kirk for $130. I went up a few sizes because the first gear was about useless and in 3rd gear it would wind out at about 25-26mph. Now he can use first and 3rd gear doesnt wind out till about 32mph. That is plenty fast for my son. He can keep up with me at a good cruise speed. I think overall that they are decent atv for the money but like you said there is plenty of improvement to be made.

 

Nice job! Since you've changed your pipe and your air intake, have you changed your jet in the carb? I'm going to do this air filter to mine too. Thanks.

 

rocketmagnet,

With just the pipe mod did not have to rejet. But with the new filter mod it does look like I am going to have to rejet carb. I will post info once I find a place to buy new jets for these carbs.

 

I think it looks real good to me smb05, And like 2manytoys says your a perfect person to have bought a chinese quad. With a few fabrication skills these can be decent quads. I had to change a few things on my wifes Yamoto myself. There is a few pics on my page of the mods if your interested.

 

mywifesquad,

Thanks, I have looked at your pics numerous times to get ideas for my 150.

Right now the quad is running very lean. But I think I have narrowed the main and pilot jet down. Still looking for the Jet needle. Will have more info next week on the jets that I purchase. Right now though if anyone is interested the Carb is a Dekni PD24J. Main jet is 111, Pilot is 35, and jet needle DB4. I measured the jets and it looks like Keihin is the winner for the jets. Now Mikuni also has a main jet that might work. If any one has any other info on these jets I would really appreciate it. Any info helps.