So my son has a little tao tao 110cc. His grand parents bought it for him. He rode it for about a year, and the little thing ran great. Then we moved, and it sat for about a year, year and a half in their garage. Finally got it moved up here, and the thing wont start. Replaced the battery. Wont start. Burnt up a starter, replaced said starter, wont start. Replaced spark plug. Wont start. Disasembled and cleaned carburetor (completely dissambled, soaked all jets in carb cleaner, blew out with air hose, verified each opening could see daylight through and not obstructed), wont start. Traced each wire looking for a short (after second starter burnt up), couldnt find one, wont start. Disconnected remote module, nothing. Disconnected rear safety lanyard at the connector, nothing. Reconnected remote module, tried using that to start, wont start. See a trend here? Now let me clarify the "wont start". I get spark. Motor has fuel. Air cleaner cleaned (even tried without air cleaner on carb to eliminate that). Starter will turn, hear faint noise and pressure from exhaust pipe, so im assuming has compression. I just cant get the little thing to fully turn over and fire up. Any suggestions? Oh, also, i drained and cleaned the gas tank too. Also tried starting it without the exhaust pipe in case that was somehow blocked up, nothing. I've got about another week of trying before I give up. He has a dinli trex too, but i dont wanna let this little quad beat me. Im thinking cdi maybe?

 

I would have Tryed the CDI first of parts to buy. Cheapest and common. Thats what I did when mine wouldn't start. $4 ebay

mine is taotao 125cc

 

Spark, Fuel, Compression.

You have spark.

After cranking the quad for a while, quickly pull out the plug and see if it is wet with fuel. Is it? Try spooning in a little gas through the spark plug (1/2 teaspoon). Replace the plug and crank. Any hint of ignition?

Remove the spark plug again. Put your thumb over the spark plug hole and press down *hard*. Crank the engine. Are you able to hold your thumb over the plug hole without air escaping around your thumb with a loud pop? You should *not* be able to hold the pressure in while cranking the engine.

Have you ever adjusted the valves? This is a required periodic maintenance item. Tight valves = no starting (or at least hard starting). Think back. Was this quad hard to start when cold before it got moth balled?

Another less common failure mode:

Sometimes CDIs fail where they trigger all by themselves independant of the trigger pulse (which is supposed to accurately time the spark plug firing). When this happens the quad gets spark - but not at the right time so the quad won't start. Bad CDI is the cause, but again this is rare. I would check everything else first.

 

I have spark, but for some reason it seems weak, i guess i just expected a little more spark. Plug is wet, ill try the compression test as soon as i get a new starter in (going to order one tomorrow off ebay). Also going to order a new cdi (cant beat $4 just in case it works). Ive never checked the valves or adjusted them. Never done this before, could you point me to a good reference for valve checking/adjustment? I have no idea where the original service manual is. Thanks for your help, its greatly appreciated.

 

Send me your email address by private message. I'll return an email with a couple light service manuals attached. Thes aren't full blown engine tear down service manuals, but they do contain necessary procedures like clutch adjustment, valve adjustment, etc.

The attachments will be around 5 MBytes total in pdf format.

 

have you tried starting fluid sprayed into the aircleaner then start it? If it starts with this you know it's a carb gas issue. If not then you know it's either electrical or mechanical.

 

Yes, i tried that when i removed the air filter and tried starting it. Sprayed directly into the air intake part of the carb. Didnt seem to help at all.

On a side note, does anyone know the cheapest place to order a new starter for this little thing? I've seen on ebay as low as $22, didnt know if anyone else has found them cheaper.

Thanks again for all your help!

 

did someone say.... blow up?

 

You did say a faint noise coming from tail pipe? you would think if it had good compression, it would pump air out pretty good, if you hold your hand over the carb, does it pull hard, or barely? Sitting for a year, the rings could have gummed up and stuck to piston, low compression will not start easy. Try some WD-40 down the sparkplug hole, let it sit over night, and see if it feels like it has better compression. Might be all it needs if it seems to have gas and spark.

 

Ill try that as well. Hopefully the starter will be here by the weekend and i can throw it on, ill let some wd40 sit overnight, and fire it up in the morning. Thanks for the tip!