Carb cleaning manual

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Folsoml
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Carb cleaning manual

Postby Folsoml » Mon May 08, 2017 10:25 am

When you first bring home your new (to you) CB650, the carbs will almost certainly need to be cleaned. This link is to a manual on cleaning the VB style carbs--like the ones that will be on your 1981 or later CB650, CB650C, or CB650SC Nighthawk.

http://www.cb750c.com/publicdocs/SeanG/ ... l_revG.pdf

This manual is actually for the DOHC style carbs like those on the CB750C, but the techniques you will use are the same.

Unfortunately, the 1979 and 1980 CB650's had PB51 carbs--which are completely different from the one shown in the manual. The manual will not help.
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fatk1d1980
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Re: Carb cleaning manual

Postby fatk1d1980 » Wed Jun 14, 2017 6:39 am

This will save someone a lot of time! Thanks for posting this.

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Hutch1
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Re: Carb cleaning manual

Postby Hutch1 » Thu Jul 13, 2017 4:37 am

Can anyone confirm if the fastener sizes listed on p. 6 of the manual apply to a 1982 CB650SC? From the manual, these are the recommended replacements:

 Qty 8 3mm x .5 x 6mm socket button-head screws (for the choke plates)
 Qty 12 4mm x .7 x 16mm socket-head screws (bowl screws)
 Qty 11 4mm x .7 x 10mm socket-head screws (air cut covers and accel pump cover)
 Qty 16 5mm x .8 x 16mm socket-head screws (top caps and rear frame)
 Qty 8 6mm x 1.0 x 12mm socket-head screws (front frame)
 Qty 23 4mm split washers
 Qty 16 5mm split washers
 Qty 8 6mm split washers
1982 CB650SC

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Folsoml
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Re: Carb cleaning manual

Postby Folsoml » Thu Jul 13, 2017 7:18 am

Hutch1 wrote:Can anyone confirm if the fastener sizes listed on p. 6 of the manual apply to a 1982 CB650SC? From the manual, these are the recommended replacements:


 Qty 11 4mm x .7 x 10mm socket-head screws (air cut covers and accel pump cover)



All of them apply with the exception of this one. Your carbs do not have air cuts, so you only need three of these. Also, since you don't need eight of these, you can get by with 8 fewer of the 4mm split washers.

If you are ordering the set from SeanG (the author of the manual), you can get the complete set for $20 shipped, so you might as well have extras. The O-ring kits he sells will also work on your carbs.
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Hutch1
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Re: Carb cleaning manual

Postby Hutch1 » Thu Jul 13, 2017 1:08 pm

Thanks Folsom, I just placed the order.
1982 CB650SC

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Hutch1
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Re: Carb cleaning manual

Postby Hutch1 » Wed Jul 19, 2017 7:08 pm

Can anyone tell me if the pictures below are part #16038-422-004 SCREW SET D? I see that the part is obsolete, and I'm missing one of the 4 screws? The overall length is approximately .8mm and the head diameter is approximately .7mm.

How can I determine the size screw and type of thread, I'd like to find a replacement at boltdepot.com.
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1982 CB650SC

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Folsoml
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Re: Carb cleaning manual

Postby Folsoml » Thu Jul 20, 2017 5:32 am

Hutch1 wrote: The overall length is approximately .8mm and the head diameter is approximately .7mm.



I would double-check these measurements. Less than a millimeter is pretty tiny.

Those screws cover the holes where you would connect a vacuum sync tool. Did you order the complete bolt kit discussed earlier in this thread? I would try those screws to see if one matches the thread. You will then know the size you need, and can just adjust for length.
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michael_650
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Re: Carb cleaning manual

Postby michael_650 » Tue Mar 06, 2018 3:44 pm

Folsom -- Can you check the link? I'm getting errors.

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Folsoml
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Re: Carb cleaning manual

Postby Folsoml » Tue Mar 06, 2018 7:22 pm

Thanks for the notice. It works for me, though. Is this the one you're trying:

http://www.cb750c.com/publicdocs/SeanG/ ... l_revG.pdf
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Efferdy
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Re: Carb cleaning manual

Postby Efferdy » Tue Jun 05, 2018 8:59 pm

Thank you very much Folsom! We will be working on an '83 right after we finished installing the new rack and tonneau cover for kayak mount on the current truck project.

michael_650 wrote:Folsom -- Can you check the link? I'm getting errors.


The link is working here in my end.

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Folsoml
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Re: Carb cleaning manual

Postby Folsoml » Wed Jun 06, 2018 6:36 pm

8) 8) 8) 8)
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wely
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Re: Carb cleaning manual

Postby wely » Tue Aug 24, 2021 9:31 am

Hello folks,

Hope everyone is going well.

Anybody know where can I find this broken niddle seat?

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