ATC70 help, spark/compression questions

[gli_ryan]

So I've been looking for one of these for a while now, and just took one home last night. Its in decent shape, but has been sitting for years. The previous owner tells me he was riding it, it backfired, and he pushed it home. Put on a new coil, and a carb, but it still isn't sparking, then he gave up. I've been messing around with it all day pretty much, and found one likely issue. The woodruff key was shot, so I replaced that. Then I was looking into the points, and noticed that when they open they do NOT loose continuity. The wire side is always grounded. I followed that wire down to the condenser and its good. Then looked at the copper coil and thats good, but it grounds out on the end, which I assume it is supposed to do. That all looks good, everything looks factory. At the condenser all the wires are soldered together, which also looks factory and it the reason why the points are always grounded. Am I missing something here?

Also I checked the compression, its low when the throttle is closed about 40 psi. But when I open the throttle I'll get 140 psi. I have no idea whats going on here…maybe the carb is clogged and no air gets past it?

I'm getting ready to call it quits and wait for a 125 lifan. I feel like it should run though once the spark arrives.

http://i127.photobucket.com/albums/p140/gli_ryan/IMG_2766_zpsd9a55708.jpg
http://i127.photobucket.com/albums/p140/gli_ryan/IMG_2776_zpsb8718202.jpg
http://i127.photobucket.com/albums/p140/gli_ryan/IMG_2777_zps14e8ba8d.jpg

[fastatc70]

Good luck with the old points stuff. I haven't had any luck. I have a couple of stator plates and coils if you want resistance readings.

I had a couple of them going but I just swaped out for larger motors

[shortline10]

Install a new set of points and condensor and also make sure the missing screw on the stator is installed again and I bet she will give you a good spark .

[gli_ryan]

that missing bolt is present, I had it off though trying to find out what was going on. Someone near me has a 125 for $100, just needs a cdi box. So I'm contemplating that, depending on how much new points/condenser is going to cost me I suppose.

[shortline10]

Points and condensor are cheap!!!!
http://www.dratv.com/atelpar1.html

[gli_ryan]

Yeah thats cheap…Maybe I'll give it a shot. but the compression issue still makes me wonder.

[shortline10]

140 on the compression is fine and the compression test is supposed to be done with the throttle open not closed .
When you get it up and running you might see a little more compression .



Yeah thats cheap…Maybe I'll give it a shot. but the compression issue still makes me wonder.

[gli_ryan]

cool thanks! I was looking for a good reason to take this motor out or leave it in. If the condenser is that cheap and the compression is fine I'll give this little motor a cha

[sledcrazyinCT]

Good luck fixing it, take your time setting the points it might take you a couple tries to gap it properly. I am considering a CDI set up for about $100 for mine - never have to screw with points again

[gli_ryan]

well swapped points and the condenser, still no spark. Tried unplugging the kill switch, still no spark. Whats the ohm reading supposed to be across the points when open? I'm only getting about .3 variation between closed and open.

[philgipson]

are you unpluging the wire going to the coil when you check ohms.

[gli_ryan]

No I'm not, I'll give that a try next time. I'll have some free time this weekend.