How to drive a motorbike?

A choke reduces the air flow to make the mixture rich. Unless the mixture is too lean because of fuel issues.

You will need to replace a gasket , from where the oil is leaking from , as you dont say from what side of the bike , you must take off any covers such as chain cover that hides the drive sprocket from the motor if that is were the oil is coming from so you can identify the exact location or wash the bike down so as to wash of most oil and then run the bike to see were the oil will start leaking from

This is complex, depends on the type of engine, and what electronics it has. You need to find out and buy a wiring loom for that bike.

I would speak to someone in the department as to what you can do as there has to be some mechanism in the system to allow for your problem. It may be as simple as signing a statutory declaration in front of a magistrate /lawyer or filling out other paper work to get you through the process.

For any 2 stoke motocross bike you can get specific two stroke gear oils from bike shop or simular just make sure it is motor bike specific as your clutch depends on it... as for brand and weights not so important just change regularly and use motorbike specific two stroke gear oil and will be just fine. I always use Bellray oils but its just personal preference and my local bike shop just happens to stock bellray products cheers mate

www.motoxpartsonline.com

Sounds to me like the fuel isn't reaching the main jet,which in all probability is due to either the needle valve being stuck and/or the float height out of adjustment

You can use the same lubricants as long as they match the specifications for your Mountain bike fork. Each manufacture of fork will provide a list of recommended weights and types for the specific fork model.

In general the mountain bike will use a much lighter weight lubricant and the heat resisitance needs are far less. So in general the Motorbike suspension fluids will be too heavy.

The Fork that is pictured in the bike represented will not work well with Motorbike oils but if you have a different fork it might.

Nice bike!
The gearbox may be save-able if it hasn't done too many miles with no oil.
I would use a good quality semi-synthetic 10-40 multigrade but for acurate description of your bike, check this web site out. It may help you out.
http://www.bikez.com/motorcycles/sachs_roadster_125_v2_2002.php

Safe riding.

Choke full on-1000rpm
warm idle-600-800rpm is my guess.

you could buy a shorter exhaust or just cut your old one short. that would make it louder the shorter it is the louder it goes