Hey, guys and gals.

Recently, I got my hands on a 2007 Buyang 110cc kids quad. When I got it, it ran great. I thought it would be a great idea to give it to my nephew for his first quad. Unfortunately, I was only able to ride it for about an hour before it randomly died on me and I had to push it home. It wouldnt crank at all. Boy was that a long push all bent over.

Some info about the quad: although it is labeled a 110cc, the engine stamp says it really is a 107cc. It has absolutely no identifying marks on it at all other than a VIN. I used Cyclepedia to find out that it is a Buyang by searching the VIN there. There isn't much info online about Buyang, but I assume it is similar to a Tao Tao. It has no gears or clutch.

I got it back to my garage and looked into some things. First, I pulled the battery and checked to make sure it had a charge. Sure enough, my voltmeter said it was putting out 14.9v, so the battery tested good. Next, I checked the starter by removing it and bench testing it. It benched fine, so this isn't the problem. I put it back on the quad and benched it on the quad and the engine cranked over. Next I benched it with the spark plug removed to see if it was getting spark and it wasn't. So I went and bought a replacement regulator, solenoid, and 5-wire CDI box and replaced these parts. Same issue. No crank.

Getting a bit peeved, I started removing the wiring harness. I was appalled to find out that either the factory or some yahoo shadetree mechanic wired this thing by twisting wires together and just electrical taping them. Thinking this was my issue, I obtained a new wiring harness. Here's where things go to hell in a hand basket.

The harness was a "direct 5-wire CDI replacement". I got it from eBay, and it was advertised as fitting Tao Tao, Eagle, and Buyang. Except it doesn't. And it came with no directions, so now I have to puzzle out how this thing fits on to my quad. Too many connectors were just wrong, so I called it a $30 loss and decided I would just run my own wiring using the factory connectors. (Meaning I pulled the wires out of the connectors, cut off the metal inserts and replaced them with new metal crimp on prongs to reinserted into the connector.) Should be simple, right?

I labeled the connectors and started clipping them. Using a few posted diagrams, I started. And I'm fairly certain I did it correctly. But the thing still won't crank at all. I on quad benched the starter again and still get no spark.

I eliminated every single kill switch on the thing except for the handlebar switch. This includes the fall off switch (the one with a tether that kills the quad if you fall off) and the stupid alarm. I'm certain there's a kill switch on the stator but I'm positive I didn't mess with that because I have never removed the stator. I did cut the connector off the harness to rewire it, but that's as far as I got.

Can someone lend me a hand? I feel like I'm missing something obvious. Having an automotive mechanical background has helped, but I'll be honest here... I failed the electrical certification and have never got it. Wiring things up isn't my strongest.

Moderators: if this is in the wrong section, please move it to the correct subframe please and thank you!

Thanks for reading and any help you can give me.

Edit: here is a picture of the main wiring harness diagram I used: https://goo.gl/images/58XUNh

Second edit: I am getting power to the solenoid. I haven't determined whether I am getting correct voltages because I lent my multimeter to a friend. I'm stuck using a "noid light", or a simple light tester.

 

This is one of those "I wouldn't have started from here" situations. Best way of avoiding confusion is to fix the fault rather than re-doing all wiring connectors as it is all too easy to introduce another fault. You need the Buyang wiring diagram. I found this on Google, http://jialong.me/buyang-atv-wiring-...kewise-bright/ pretty poor and annoyingly, found a better one, but the link from Google's thumbnail to it doesn't work.

 

I was under the impression that I was fixing the fault as the wiring harness wasn't soldered at junctions and was instead just twisted together and electrical taped.