airfilter oil urgent!

Nope, best off just to get air filter oil. If you have a K&N you can get a recharge kit. But K&N still suck too much dirt. If your running a foam filter then get filter oil its thick, very sticky, impossible to wash off your hands, and is certian to make a mess. but it keeps your engine safe.
 
ive always used motor oil it works fine

i just use the leftover yamalube from the trans

the manual says its ok too
 
While those might work in a pinch, why risk it? A bottle of No-Toil or UNI filter oil isn't very much and will work much better. Unless you just really enjoy changing rings all the time. Even Bel-Ray isn't as thick as filter oil and its not tacky like it needs to be. Filter oil is thick like honey and also tacky like honey (and no you cant use honey:-D)
 
streight from wiki

SAE operates a separate viscosity rating system for transmission oils which should not be confused with engine oil viscosity. The higher numbers of a transmission oil (eg 75W-140) do not mean that it is necessarily higher viscosity than an engine oil.