Motorcycle Repair: throttle wont reverse itself, gas leaks, honda cbr

Question
hello Wayne,
I am having 1989 honda CBR, and throttle won't reverse itself.  When I rolled on throttle and release it, it will stay and won't go back unlet I roll it forward.  Do you think maybe spring problem on the caburator side or cable itself.  

Another problem is that I smell alot of gas after starting a bike.  For example: if I started a bike in a garage for 5 min, and I a smell of gas stay for couple days.  I shutted gas after 5 min.  There is no side of leaking gas.  What do you think the problem is.  Please be adviced and thanks very much for your time.

Thanks

Don

Answer
Don,

-check the throttle spring, but most likely
it is the throttle tube or grip sticking.
Sometimes the end of the grip will rub
on the handlebar. Just loosen and clean
or lube it with something thin.(armor-all)
Possibly a sticky cable also.

-check your oil for gas smell,
maybe some gas has leaked into the oil.
Are there any loose hoses on the emission
canister? The gas tank vents into this
canister. If the hose was cracked or loose
you will smell gas.
Try an oil change and check the air filter,
if you see no gas leaks, the carb float needle
valves may be leaking internally into the
engine and down to the oil.
May need to replace the float needle assy.
eventually.