ATC70 swap questions

[dcreel]

I'm looking to put either a Lifan 125 or 140 manual clutch motor in my atc70. I have some questions that some of you guys (Kasey) have come across.

What are the differences between the 125 and the or a 140 Chinese motor? Is it worth the extra money? Is an oil cooler a good idea for either the 125 or 140 motors? The 140 Lifan comes with an oil cooler.

To add the clutch lever, can I use the rear brake hand lever with the clutch cable (and add the foot brake) or is my best bet to use an aftermarket set of handlebars?

What do you use for an on/off switch for the motor? Can you use the stock thumb throttle and on/off switch?

To run the 125 or 140 is it neccesary to stretch the frame, or will the cylinder head clear the front fender? I realize it will fit an adult better stretched 3".

These are the motors I'm looking at:

140
http://www.ebay.com/itm/160685225459?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1423.l2649

125
http://www.ebay.com/itm/310379727713?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1423.l2649

Thank you for any info you can offer.

[MisterFurious]

I used the 125 when I did mine; instead of stretching the frame I cut a wedge out of the tube and bent it together and re-welded it, gave it a couple inches of rake. The head would not clear with some sort of mod. I also had to dent the underside of the gas tank to clear the carb, since the intake is angled out. I cut the brake lever mount off the handlebars and mounted a clutch lever and mounted a brake lever from a 110 on the throttle side. Also welded a 1/2 drive socket on the kick start post to start it with a breaker bar; mostly I bump start it, though. I believe I used the chain from the 110 as well. Hope this helps...

[hoosierlogger]

Yes you can use the brake lever bracket with the clutch cable.

I used a round push button kill switch. I dont see why you you couldnt use the stock throttle.

the 140 will need the frame stretched a couple of inches.

See my 140 swap thread in my sig line.

[Mosh]

IMO unless you are a big dude, the 140 is too much. It will actually wear you out. You can ride the 125 harder and faster and longer over the 140.
You also can get away with no oil cooler on the 125 unless you are going to run the snot out of it.

You can use the stock thumb throttle and kill switch. But hooking up the cable will pose problems to the stock thumb. It can be done. some tell me a 110 cable works perfect, but I have not tried it.
Generally I use a 300 ex thumb throttle and a Pirhana twist cable. I use the old elbow from the 70 carb cap, drill it out and use it on the bigger carb and all adjustments on the cable can be done at the thumber. It has a better smoother throw, and wont wear your thumb out as fast. And you can set it anywhere you want on the bars. The stock thumber has a locating pin for the bars you will have to grind off.

We use aftermarket pit bike bars and a clutch lever, and move the rear brake over to the right side of the bars with a second clutch lever, and hook up the clutch cable on the left side. Your stock brake cable will be long enough with pitbike bars.
The motor may hit the front fender depending on what engine you use and how straight your frame is. But you can trim about 1 inch off the rear of the front fender and it should clear.
If you go with the 300ex thumber, just hook up a dirtbike push button kill switch in line with your coil and ground to kill the engine.

Honestly if you are not going to be "racing" the 70, the benefits of the auto clutch engine outwiegh the manual IMO.
If you do get a manual motor get the kind with the top clutch actuator, not the side mount one.
The last lifan 125 Auto kit I put in a 70, the carb went right on with with no mods to the tank other than shimming the rear up with a few washers.
The pirhana 125 engine kits, you will fight carb clearence issues unless you get the drop down intake tube for the 70 application.

[dirtjunkie85]

In my opinion and what a friend and I did was go with a pisterpro motor such as the 150 or even 175. Pretty small, easy to mount up and depending on whose riding or how it's being ridden you have torque for some wheelie time or turn it down with just a throttle adjustment and let the little ones cruise around on it. We also left it in the completely stock frame, no added swing arm or anything.

[Jon Boy]

In my opinion and what a friend and I did was go with a pisterpro motor such as the 150 or even 175. Pretty small, easy to mount up and depending on whose riding or how it's being ridden you have torque for some wheelie time or turn it down with just a throttle adjustment and let the little ones cruise around on it. We also left it in the completely stock frame, no added swing arm or anything.
so just how small are the PP150 and 175? everything i've read says the frame needs stretched if bigger than a 125. also what do you mean "no added swingarm"? the 70 has no suspension to begen with.

[dirtjunkie85]

No like how most people will actually fabricate a swing arm for the 70 so that it's longer or something of the sort. We didn't have to necessarily stretch the frame but we did turn the motor and did weld a so called bracket in the front. Give me a day or two and I will post a picture of it to show what I'm trying to explain