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1982 CB750SC Nighthawk Resto

TheDrummer212

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I recently traded a pit bike for this Nighthawk. Since I only had $100 into the pit bike, I essentially got this for that much. The guy I got it from had gotten it on trade, and knew pretty much nothing about it, except that it cranked over fine. Not horribly promising, but for such a low price I figured why not. As far as I know, it has sat in a field for at least 5 months. Here are some pictures from when I got it.

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Just under 12k original miles.

Problems it came with:
-Didn't run
-Smashed right side mirror
-One emblem falling off
-No brake fluid/brakes
-No title

First thing I did was remove and clean the four carburetors. In the process I found there was no air filter in the dirty airbox. I put the carbs back on the bike and cranked it over. Still nothing. I decided to take off the gas tank and flush out the rust-colored gas. Also found a clogged fuel line. Replaced that and the bike started right up, but there is a steady flow of gas out of the overflow tubes. More updates to come soon.
 
Lucky DUDE! Looks complete too. I have a 83 750sc project bike that my grand-son has picked out for when he's bigger. :bike: From 2 sc's I am still missing the rear cowl, OF COURSE.....

I know that removing the carbs is a real pain at best. I bought my wife a KAW 500 Vulcan much the same as your sc, years under a tarp out side. Even after cleaning the carbs a few times they still leaked(?) - overflowed. So, with Lots of gas w/Seafoam things started working good. Then it sat for a couple months and troubles again. If you get it working don't let it set, keep proper amount of Seafoam in gas. Its that or sonic cleaning and ............ a lot of little parts and stuff. :thumbsup:
 
If they use ethanol where you are much of the problem. Ethanol in fuel is pretty transparent as long as vehicle used every day but let it sit and the problems begin. I let my stuff sit a long time and no trouble until the ethanol showed up, then repeat flooding carbs as the float needles stick, you can touch them lightly with finger and fixed but you have to yank carbs to do that. I began to run the fuel completely out dry and much better then.

Ethanol ramps up gas evaporation like mad, spill some in summer and see how the spill can be gone in seconds. With that it dries up fuel in carb bowl lightning fast and why these carbs mess up so easy, they clog the idle feed super small holes first. Clogged idle on these is double bad because the idle is linked to primary mainjet in a seesaw system and then primary goes super rich because idle is lean. Good one, eh??? Why these carbs throw most experts for loops.
 
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