HONDA CUB 90 SMOKING

[angelapod]

WAS JUST WONDERING TERRIBLE SMOKE COMING OUT OF THIS HONDA WHEN YOUR DRIVING IT, WHAT COULD THIS PROBLEM BE AND IS IT SERIOUS THANKS

[pauric141]

is it burning any oil ?

[Josh8178]

Probably worn out barrel/piston. top end kit is about £45 on ebay, an hour job at most and that includes removing stubborn gaskets!

[Jon]

I had smoke coming out of mine and it turned out to be very old petrol. however, if you put petrol in it recently the nature of the problem depends on the colour of the smoke. If it is blue, then it is burning oil. If it is dark geay/black, it's a fuel problem and your choke might be stuck or the carburettor has a problem.

If your bike is smoking blue smoke badly it will probably be burning a lot of oil and will very quickly run out of oil and then the engine will destroy itself ...So...you MUST check your oil level immediately ( unscrew the plastic oil filler plug, wipe clean the dipstick, then, with the bike upright and level (rest it carefully against a wall but not leaning over so it's nearly falling) put the filler back in but NOT screwed down...just resting in the hole. Then check the level on the bottom of the stick. Ideally it should be covering the hatched area. Top up as necessary. This will keep the other bits of the engine in decent condition.

if the engine IS still running then repair is not too bad. It may need some parts replaced but the bits it may need are cheap and the work is easy. I suspect it may need a new piston and rings and the cheapest solution is to buy a new piston, rings, barrel and gaskets. They are around £60 delivered off eBay and any reasonably competent 'first time' mechanic can fit it all in about two hours.
Whatever happens you are probably going to have to take the top of the engine apart so it's almost worth simply replacing those parts anyway

Hope this helps!

[angelapod]

no dont known if it is burining oil or not

[Pjam]

Blue smoke = oil (open up engine and check for wear)
white or grey smoke = burning fuel (check carb for wear/adjustment)

Apart for that, as guildbass sayS, old fuel or water in fuel perhaps?

[Jon]

Blue smoke = oil (open up engine and check for wear)
white or grey smoke = burning fuel (check carb for wear/adjustment)

Apart for that, as guildbass sayS, old fuel or water in fuel perhaps?

The only time I've seen white 'smoke' is when it's water vapour. Generally when the condensation in an exhaust pipe is heated first thing in the morning after a cold night, or if a water cooled engine has a head gasket problem and the water is getting into the cylinder head. This time of year there isn't enough humidity to deposit enough water in the pipe and I doubt if a Cub will run with enough black fuel smoke to be visible.

The water in the fuel made mine smoke horribly...Not sure why actually...unless there were other things in there too. It ran terribly lean as well...you'd almost suspect a petroil two stroke mix...Except i don't have anything two stroke...Very strange!