Anyone know whats up here?
 

Hey guys...My brother's Gy-5 just came in and we spent all day going over and assembling his bike. After dropping the battery in and filling the tank, we tried to start it and all we got was the starter turning over and nothing from the engine. We removed the starter gear cover and bumped the stater a few times. The starter in turning the gear but its not engaging the engine at all. I think it could be the sprag clutch slipping. I pulled the gear out and turned the internal gear by hand. I rotates in one direction but not in the other. This confirmed that it is a sprag clutch. The question is what can be done to get this clutch to engage. I thought it couldve been just from sitting up with the factory oil and lost the friction due to film build up. I dont want to tear into his engine just yet. So if you guys can come up with anything let me know.

Does the kick starter work?

Or does it push start?

Sure does, kick your ass off but she runs. It just seems as though theres way to much slippage on the sprag or the starter isnt spinning fast enough....?????????

You sound very mechanical, so please don't take this wrong.
Did you charge the battery well before using it?

Is the starter whiring (sorry about the hi-tech words) around but not turning the engine at all?

Charge the battery.

Problem solved guys and you wouldnt believe what it was. It wasnt the battery and was nothing you guys would ever guess. After a few calls to Bruce @ EJCycles, he and I poured over almost every possible cause and couldnt come up with anything. BTW if you guys ever need technical support Bruce is the man...and I do mean the man! Ok back to the solution, I went over the schematic over and over to the point of memorizing it. I took out my Fluke and started checking for power at every plug, and low and behold...ALL THE HOTS WERE GROUND AND ALL GROUNDS WERE HOT! Every plug was wired for reverse polarity. After switching the pins on every plug I got all the electrical problems solved except for the starter...I pulled the ignition and it was the same way. As I turned the key it reversed polarity to the starter causing it to turn backwards free spinning the sprag (if you know how a sprag works you'll know what Im talking about). Thus not engaging the engine. Some of you guys are thinking why didnt I just switch the leads on the battery...Well if you look on the schematic, you will see that you have a rectifier and diodes, reversing the leads would have fixed only 25% of the electrical problems except for the components connected to the rectifier and diodes. I mentioned a sprag earlier, for the ones who havent seen one, what that is, is a one clutch or one way bearing. It will free spin in one direction and grab in the other. This is how your starter cranks the engine, once your enging is started, centrifical force disengages the sprag not allowing the engine to spin the starter. The sprag is an actual bearing and not a true clutch, clutches usually comprise of springs, drum, disk or some kind of friction material. A sprag is an actual roller bearing(s) and is located on the back side of the flywheel, it has frictional material on the faces of the cage to allow lock up, theres is also a housing that the sprag sits in and has detents which keeps the bearings free spinning in one direction. This housing is attached to the flywheel and provides the centrifical force to seperate the sprag thus keeping the friction material from burning up. My bros GY-5 is a grey Lifan which he bought from the internet, compared to my American Lifan the 2 bikes are identical but once you remove the fairings the grey Lifan is a totally different animal. Quality is not even close to the American Lifan, the frame is different, the wiring harness is different as well as a few other items. There nothing on the bike that is stamped with LF, American Lifan stamps just about every single part with LF even the heads of the bolts. Learn a lesson from this nightmare and DONT BUY A GRAY LIFAN! Get yourself an American Lifan from a respectable dealer like Bruce @ EJCycles. Thank you guys so very much for the input.

Good info and great advice. Thanks. :D

Wow...I would have never figured that one out!
Bruce saves the day again!
I said the same thing after buying from a non dealer. (Mine was an MSO problem not mech/elec)
Go to a real dealer that carries the real thing, especially if you are not mechanically minded.

I have a grey Lifan and quaility is actually pretty good and most things seem to be stamped LF.
But it does seem that the bikes can be ordered all sorts of diffferent ways.
I wonder if the Chinese are counterfeiting their own bikes. :twisted:

I think the difference between bikes is the company owner or rep actually watching the assembly. I think that the owner of, let's say, Roketa, uses an OEM manufacturer to make their bikes. If they are conscientious, they will visit the factory where their "brand" is made, and ensure that they are assembled to their specs. (There are probably a few options to choose from, such as rear sprocket size, though most seem to choose the 56 tooth).

The American Lifan rep is probably doing this to eliminate many of the warranty headaches. The Chinese Lifan company is just making bikes, and shipping them to importers. I bet the American Lifan head is kicking himself for not ensuring that his company is the only importer, rather than the official importer of Lifan bikes!