There are two types of oil that are recommended to be used in a 4 stroke dirt bike. It is recommended that you use motorcycle transmission/gear oil in the transmission side and usually 10W-40 motorcycle oil in the other side. Some people, use 10W-40 in the transmission, but I don't do this and the factories do not recommend it.
The quicker 2 stroke dirt bikes use a gas/oil mix. Most bikes you see on the road are 4 stroke and use regular gasoline.
No we can't use 100cc 4 -stroke dirt bike race against 85cc dirt bikes.
All of the Orion bikes use a 4 stroke engine.
No
Assuming you are referring to a street legal motorcycle (IE: Kawaski Vulcan, Ninja, etc.) these machines have four stroke engines. Dirt Bikes and such sometimes do not. Two-stroke engines generally use a fuel+oil mixture. (Such as a weed whacker) Four stroke engines generally have an oil sump. (Like a car)
The motor oil to use in a 1982 Yamaha 250 XT 4-stroke dirt bike is a 10-30 or 10-40 weight oil. Castrol GTX Motor Oil that is of this weight is the best oil to use in off road bikes, because it is a cleaner oil. It will not gum up the works of smaller engines like regular motor oil.
Soy
Best to use two stroke oil. Mix it with the petrol, (I guess you know this)
For stroke engine bikes use the engine oil as gear oil. In case of a two stroke engine you can use regular 80 W / 90 gear oil.
Depends on the manufacturer as to what type and weight oil to use.
Dirt bikes come with a MSO (manufacture statement of origin). They have OFF ROAD USE on them. The dirt bikes that can be tagged for road use will have an actual title.
a half of quart 2 stroke .....2 stroke oil mixes with the gas only!!! use automatic transmission fluid type f for your gear oil..DO NOT USE 2 STROKE OIL FOR GEAR OIL!!!!