I just recently got a 1983 Honda vf 750 s that had been sitting for a few years. Everything seems to be in pretty good condition. I have done some basics on it prior to trying to start it to make sure it is good to go. New battery, starter, spark plugs, changed oil and filter, changed coolant. I have taken the gas tank off due to there being some rust inside. It is currently being de-rusted. Yesterday I cranked it up for the first time it ran by putting either gas or carb cleaner through the fuel line, but only on full choke and only after it got warm could I give it any throttle (and barely any at that, before it would die). I have put a can of sea foam through the carbs by way of the fuel line, put some in and let it sit for a few days hoping it would clean any gunk out. I suspect that the carbs have got some issues and I may have to attempt pulling them out and cleaning them. Today, I tried starting it again and got it going for a little while (again on full choke with no throttle), but after not too long, it stopped and would not start at all. Another issue it has and is kinda giving me a scare is when it has been running, there is pretty thick white smoke coming out of the left exhaust pipe. What could this be from and what do I need to do to fix it?

Any comments or suggestions would be greatly appreciated.
Thanks!!

 

could be where its sat so long or coolant leak headgasket

 

I think you might have just found the reason it had been sitting for a few years!
Can you get any information from previous owners?
Any blue-ish tinge to the smoke or does it smell like burning oil?
It's probably oil or coolant (assuming it's liquid cooled) that's getting in there somewhere, an engine compression test might show you what cylinder/head is in trouble. (or even a quick look at each sparkplug)
If it's oil thats burning, you might need to replace valve seals or piston rings, or the gasket, or the cylinder barrel could be damaged.
Coolant can also enter the cylinder if gasket is gone/head warped.
Heads warp from overheating, if that's the case you'll need to find what caused it or it might happen again after the fix.

Either that, or you've killed it with seafoam lol
Good luck, let us know how you get on with it.

 

Ah gee tom, this is from a month ago?? He's hardly gonna check back now!

 

i have a problem with my run stop switch. i am trying to by pass it any ideas?