'82 CB650 Nighthawk cafe.....say what?!?!

CB650Ben

Got a lot to learn....
So I bought an '82 CB650sc for just over a half bill. The motor has 11K miles on it, and is in great shape. Hooked up a battery, and sprayed starter fluid in the airbox, and she fired right up! I know these clunky old things, don't make the cleanest cafe racers, but I'm gonna try. The P.O. did a halfway job trying to café it. He did a decent job on the steel seat pan, but did a hack job on an old Kawasaki Avenger tank, trying to move the petcock, and make it fit (lot of JB weld, no cap, rust inside, etc.), so i bought an old CB tank off of ebay (looks like an old 450 or 500 tank, it's on it's way). So here is the bike when I brought it home. My first goal is to just do the minimal to get it back on the road. I live in the NC mountains...great summer weather, and great curves.
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Here it is with the tank and seat off. I slid the forks down a bit, just to see how it would look with clipons later, or if I lowered the forks (I've already been informed that they won't work like that).
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Here it is with the seat pan. The seat got a little off center with his lines, if you look at it from the back but I think i can build up about a 1/4" of Bondo in layers and minimize how noticable it is. I've heard not to go more than 1/4" with Bondo.
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Here is the mess that is the fork area. The P.O. had chopped the original handlebars to mount at about 90°. I'd like to get some clip-ons down the road. Any ideas on how I could clean it up?
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And here are a couple of quick sketches, with what I would like to do to it...pardon the inaccuracy of the tank shape / mediocre artistic ability
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Anyway, I have sourced a few parts I need: brake adjustor, new tank, exhaust flange, and fork air valves (thanks to Swivel), so when I get all of the parts, I should be able to start her up. Wish me luck!
 
thanks Swivel! I know man, you already told me about the forks, remember? ;) That's why i put the disclaimer above the picture. The throttle isn't tightened down, I had to sand the paint off the bars, it was causing the throttle to stick, also, I think I have some cable tension issues, since the bars have been dropped. I guess I might need shorter cables? But yeah, the bar looks all janked up because I just slid the throttle halfway on for the pic.
 
This is what I was thinking for the plate / tail light:

http://www.ebay.com/itm/BOBBER-VERTICAL-BLACK-LICENSE-PLATE-BRACKET-BRAKE-TAIL-LIGHT-615-/120917071769?pt=Motorcycles_Parts_Accessories&hash=item1c27381799&vxp=mtr

Swivel, are these the kind you were thinking of as a PITA?
 
I got the new tank in today, gonna work on it tonight. I got the tank off ebay, and all I know is that it's an old cb tank of some wort. Can anybody help identify it? I think I'm going to have to rig up a bracket for the rear of the tank, and relocate the petcock. Can anybody point me to some good threads / info on moving and rewelding a petcock bung? Or another solution? I've heard they can be a real PITA to get watertight.

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Here is a close up of the current petcock bung. It sits directly over the carbs, so I think I'm going to have to move it in front of the carbs on the other side.

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Found a guy nearby who can do it, if I need him to. Next question, would there be a way to install like a small 90° elbow joint for the fuel line and then have an inline petcock? Or any other ideas to avoid having to move the petcock?
 
Do you think it would work if I fit a low profile one like this with an inline fuel filter?

http://www.dimecitycycles.com/vintage-cafe-racer-caferacer-bobber-brat-chopper-custom-motorcycle-carburetor-tank-parts-npt-fuel-petcock-54-12-0039.html

The one that's on there now looks like this one (below), and I don't think I need a petcock with a duel fuel line...

http://www.dimecitycycles.com/vintage-cafe-racer-bobber-brat-chopper-custom-motorcycle-fuel-tank-parts-honda-cb450-fuel-petcock-16950-292-000.html
 
So, here's an update. I haven't posted in forever. The weather is getting warm here, and I've been back to work on the bike. I'm really close to having a rideable bike, which is really exciting. Here's some recent pictures. I just have a coat of primer on it for now. I'm still deciding on color:

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I am having an issue with my LED brake light that I bought, however... The running light works, and the brake light works, but when it's running and I hit the brake light, it doesn't get brighter, it stays on the running light. Any thoughts? Or could anyone point me to a previous thread?
 
Are you sure you didnt get your wires switched on your LED tail light? If your brake light was on as a park light it wouldnt get any brighter when your brake switch came on.
 
It's possible, but the brighter LED is on the brakes, which seams right, and when it's in park the dimmer light along with the license plate lights are lit up. It seems to me like they're both working separately, just not together...would it be a voltage issue?
 
Also, I'm having trouble getting her started. I'm getting spark and compression, so I think it's a fuel issue. I took out the spark plugs from the outer two cylinders, and poured some gas directly in, and it started and ran for just a second. So I thought it might be the cards, but I took the float bowl and the top of one of the carbs, and they looked clean as a whistle inside. then I hooked the tank back up and waited a while, then opened the drain on the bottom of one of the carbs, but got nothing, so I'm not sure if fuel is even getting to the carbs. Does anyone know anything about the automatic fuel valves on these things, that the fuel goes into before the carbs???
 
CB650Ben said:
Also, I'm having trouble getting her started. I'm getting spark and compression, so I think it's a fuel issue. I took out the spark plugs from the outer two cylinders, and poured some gas directly in, and it started and ran for just a second. So I thought it might be the cards, but I took the float bowl and the top of one of the carbs, and they looked clean as a whistle inside. then I hooked the tank back up and waited a while, then opened the drain on the bottom of one of the carbs, but got nothing, so I'm not sure if fuel is even getting to the carbs. Does anyone know anything about the automatic fuel valves on these things, that the fuel goes into before the carbs???

IIRC your petcock has three settings: On, Res, Pri. "Pri" allows fuel to flow without using the vacuum method and should provide fuel to the carbs even if the little diaphragm inside the petcock is shot.

Pull the fuel line(s) off the carb(s) and see if you can get fuel to flow. If not, you need to clean and possibly rebuild the petcock.

If fuel flows freely from the line, then you have an issue - likely with the floats - that is preventing the bowls from filling with fuel.
 
Get rid of the automatic fuel valve. It is called the spawn of satan for a reason. I it very easy to remove IIRC. Check here for info. If you cant find any check out cb750c.com. They have great info there about removing it. Here is a pic of my 82 Nighthawk 750. It has a 5 inch rim and a 180 rear tire.
 

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Nice bike! Also, great info! I bypassed it, and just went directly into the carbs from the tank petcock. She fired right up! Still doesn't stay running unless I keep gassing it. The carbs may need syncing. I took one apart and it was clean as a whistle, so I don't think they need cleaning. The bike set dry for over a year with no fuel in it. Any thoughts? Here's a YouTube video of the first start up. Took a bit to get it going:

http://youtu.be/XAvykh33Npg?t=29s
 
The carbs on these bikes are a real pita for sure. Make sure the air box is on and sealed and also the boots between the carbs and head. Have you tried turning up the idle with the adjustment knob?
 
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