ATC70 Bogging Down

[3wheelers]

So I bought an ATC70 that's in pretty good shape. It had been sitting for 4 years. I got it, took it home, cleaned the carb, and filled it with gas. It started up, and idoled perfectly, but it won't take any throttle. It dies immediately if you press the throttle at all. Assuming I didn't give the carb a good enough clean. So I took it off, cleaned it out real good again, and put it on. And it still has the same problem, idols but won't take throttle. I adjusted and tweaked the carb, didn't help. Sometimes it would take a little throttle when it was cold. But once warm, it has no chance of taking any throttle. What could be the issue? Could it need new points? Or maybe do the valves need to be adjusted? Could the carb just be junk? Maybe it needs a new coil? If anyone has had this problem and fixed it or have any idea what it might be, let me know. Thanks!

[webbch]

Check to make sure you didn't install the needle jet backwards...I've done that before with those exact symptoms being the result - idled fine but wouldn't take any throttle at all.
http://img.photobucket.com/albums/v708/webbch/Misc/needle_jet_zps840b0b2a.jpg (http://smg.photobucket.com/user/webbch/media/Misc/needle_jet_zps840b0b2a.jpg.html)

One end of the needle jet has a larger opening (the one NOT shown in the photo), so if you can look through the carb bore and what you see resembles the end shown in the picture, you have it installed backwards

[aefultz]

Im having the same problem with my 110 i put a new carb on it and it did the same thing ?

[3wheelers]

My jets are in the right way and they are in the right holes. Aefultz, did it have the problem before you put the new carb on? Or just after you got the new carb on? I'm thinking maybe it's somthing electrical? Or maybe the valves need to be adjusted?

[CRAZY70MAN]

Your pilot jet or one of the passages are plugged,most likely the pilot jet. Did you unscrew the jets themselves and run a small wire thru them? Pull a long wire from a wirebrush,straighten it and use that along with compressed air. 90% of the time the pilot is plugged vertically. Not the several small holes at the bottom,but thru the jet itself. Sometimes takes a pretty good effort to get it cleared.try soaking it in blaster or evaporust if it is that bad. Soak entire carb after you remove all circuit screws and float needle,the will gum up also. I would bet your idle jet is plugged though.

[webbch]

Assuming the OP disassembled and individually cleaned the jets/blew out the passages (but good idea to confirm).....I'd think an off-idle issue would primarily be needle and/or needle jet related. It's possible that the PO messed with the carb and installed the incorrect needle jet and/or needle. A carb kit would have replacements for these items. Also, what groove is the needle clip on?

[briano]

I'm willing to bet it needs points. 70s are pretty fussy with their points and can act like carb problems

[3wheelers]

I just adjusted both valves and I sanded down the points and adjusted them, and it worked! It's running great now! It was either the valves or points. Most likely was the points. Thanks for all your help and suggestions guys!

[webbch]

Good to know and thanks for posting what worked. My trikes are all CDI - didn't know that points could act like that.

[aefultz]

3 wheeler it was doing it before with old carb and with new one it will idle Fine and we'll bog when you give it throttle if you choke it it runs fine .mine has cdi i will try to adjust valves to see if it works

[3wheelers]

I have had a similar problem with my 110, it runs fine if the choke is on, but if I turn it off it will die with any gas. But once it's warmed up it will run ok without the choke. I'm not sure what the problem is, but it doesn't bother me. I just run it with the choke on.