First project: high idle (4k), ignition lock cylinder issues

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Hydefree
Posts: 3
Joined: Thu Mar 02, 2017 6:15 pm

First project: high idle (4k), ignition lock cylinder issues

Postby Hydefree » Sun Mar 05, 2017 8:24 pm

First bobber project
82 cb650
Threw a new battery in it and got it fired up.
Idled a little high at first (around 2k). Now after riding a few miles it idles about 4k. I've checked for vaccum leaks and found none. I believe one of the float adjustments is off because it leaks a little fuel.
Any suggestions?
The ignition lock cylinder was a little touchy at first and after riding for the same few miles I shut it off and now it doesn't work at all. I'd tried fidgiting with it to see if it will still make a connection but nothing works. Is there a way I can wire around it and throw a switch in?
Thanks for any input.

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Folsoml
Posts: 1634
Joined: Sat Apr 07, 2012 9:02 pm
Location: North Florida

Re: First project: high idle (4k), ignition lock cylinder issues

Postby Folsoml » Mon Mar 06, 2017 6:06 am

On the 1982, the floats were not adjustable. Have you tried tapping the float bowl with a screwdriver handle to see if you can get the needle to seat? If that doesn't work, check the drain screw to see if it may be damaged. If that's fine, you may need to pull the carbs to inspect the needle and needle seat.

When you say the ignition lock doesn't work, will the key not turn, or is it just not powering up? If it turns, sometimes you can just turn it on and off rapidly about 50 times and it will clean the connections. If that does not work, here is a link to an instructional post on how to rebuild them:

http://www.cb750c.com/modules.php?name= ... pic&t=6204
Have a problem with your CB650? Have a technical question? Click here!


My Current Bikes: 2005 HD FLHTCUI Electra Glide Ultra Classic, 2007 Yamaha Vino,

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tario
Posts: 166
Joined: Sat Mar 07, 2015 2:26 pm

Re: First project: high idle (4k), ignition lock cylinder issues

Postby tario » Fri Mar 10, 2017 1:59 pm

Does the fuel line run from the tank to a little aluminum dohicky bolted to the carbs? Then run down to the carbs? If so that is a vacuum fuel shutoff. It can cause fuel starvation problems. You can just remove it and run fuel straight to the carbs. (Many people do this) Just block off any hoses that don't run to a carb fuel inlet. Other than that it could be the regular carb problems.

If you check your sparkplugs you can tell what the fuel mixture is like on each cylinder. If it's white and a bit crispy it has too much air. If it's black and a bit greasy or sooty there is too much fuel. If it's tan and maybe slightly white it should be about correct.
1979 cb650
1980 cb650

Hydefree
Posts: 3
Joined: Thu Mar 02, 2017 6:15 pm

Re: First project: high idle (4k), ignition lock cylinder issues

Postby Hydefree » Sat Mar 11, 2017 9:47 am

Update on the ignition issue.
I removed the switch and tested for continuity with the key on. It has continuity and has between 4.8 and 6.8 ohms of resistance.
Could there be an issue further up the line causing no power when the key is turned on?

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Folsoml
Posts: 1634
Joined: Sat Apr 07, 2012 9:02 pm
Location: North Florida

Re: First project: high idle (4k), ignition lock cylinder issues

Postby Folsoml » Sat Mar 11, 2017 7:00 pm

Check the master fuse. It is on the starter solenoid under the left side cover. If it is burned out, you will have no power at all.
Have a problem with your CB650? Have a technical question? Click here!


My Current Bikes: 2005 HD FLHTCUI Electra Glide Ultra Classic, 2007 Yamaha Vino,

Hydefree
Posts: 3
Joined: Thu Mar 02, 2017 6:15 pm

Re: First project: high idle (4k), ignition lock cylinder issues

Postby Hydefree » Mon Mar 13, 2017 6:08 am

Good call on the fuse. I checked and someone had replaced it with a piece of wire that had pulled out of the crimp connector. I have since installed a blade style fuse block in its place with a 30A fuse.

To add to this thread..
I have a cb650c parts bike with excellent tires where mine currently are pretty dry rotted. It also has more desirable spoked wheels. I would like to swap these wheels and tires but the front only has a single disk where the complete bike has twin disks. Can I just swap the wheels and plug off one of the lines and remove the extra caliper? Or do i need to swap the whole fork setup?
Thanks for the input.


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