Motorcycle Repair: BRAND NEW BIKE PROBLEM, brand new bike, importing electronics

Question
Hi,

My name is NAGY and I am a fellow Expert in Home entertainment and satellite TV.
I will include my email address is case we are following up on the problem I have since I have pictures I would like you to have a look at:
nagygeorge@optusnet.com.au
I live in Melbourne AUSTRALIA and I've got an Engineering degree in Electronics.
I have been importing Electronics and computer peripherals for years from China but recently I have ventured in Dirt Bikes' Imports.
I have imported 125cc 4 stroke, 1cylinder, 2valve dirt bikes replicas of Honda from a manufacturer called Apollovehicle (www.apollovehicle.com)
To make a long story short, I have only sold ten  or 12 and I already have BIG problems with 2.
The second one I haven't checked on yet as it's an interstate customer but the first one I have already replaced to the customer and I am trying to see what could be wrong with it.
Customer bought on a Saturday, called be back Sunday saying he's got problems with it, I go and see him on Monday and the problem is:
Bike is very hard to start and when it does it only runs with chocke ON even after warming up the engine and is dripping oil heavily.
I tried a new carby and air filter with same problem.
I followed up the dripping and it came from under the engine cover, I took the engine cover off and it is dripping (or rather spraying if I can exagerate a bit) oil from all around the small sprocket.
Engine is not even 1 day old.
Could the customer have done something to the first engine run that caused that?
Let me add that for transport, the engine breather comes with a cable tie, when I went to see the bike the tie has been removed as per assembly instructions but if it hasn't been removed could it have caused that (I am thinking if customer didn't do it at first and is lying to me)?
Could the oil coming off around the sprocket and sprayed by means of the chain when it turns, affect the magneto and causing thebike to idle if not in choke?
As I said before I have some pictures if interested and sorry if I wrote a bit too much.

Any and all help appreciated (also any website addresses to read about engines, bikes and repair would be appreciated)

HAPPY EASTER

NAGY


Answer
Hi Nagy.

That's a pretty complex set of circumstances.  I've been hearing a lot, both online as well as here on the streets about those Chinese copies of Japanese bikes.

First thing that you need to do is get the repair manuals for each of the different models that you have there.  make sure that you get the factory manuals.  If you can't get them, then try to find the bikes that they are copies of and get the repair manuals for those.  It will work in a pinch for this until the proper manuals are available.

There's a couple of issues that could be going on.  One is that there is the possibility that the buyer could have run the motor too hard or may have used pre-mix fuel by assuming that it was a 2-stroke.
 Is it possible that the oil was overfilled or that the motor wasn't tightened down and set up properly?
 What about when the bike was initially set up for the local customer; Was the engine checked out and run to check for proper operation?

Start with those possibilities and I will drop you a direct e-mail from my personal e-mail so that we can try to sort this out more thoroughly.

Happy Easter

FALCON