Author Topic: CB carb trickery  (Read 692 times)

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Offline club_c

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CB carb trickery
« on: February 12, 2023, 01:27:41 PM »
Hello Honda fans, I’m a long time rider and Honda owner (as well as BMW). I’m currently working on a 1980 CB650 Custom bike. 32,000 km, came to me in pieces, a non runner with no history. After a lot of tinkering I have it running ok, and am trying to improve the infamous hard starting when cold. In my research the accelerator pump has been mentioned. In examining my pump I see that it doesn’t really operate. I believe the culprit to be the top spring. It was missing but I found one with the carb parts and thought it was correct. But it can’t overcome the spring behind the pump diaphragm at the carb bowl. Any thoughts to correct this?  Any insight as to what kind of stronger spring I could find to use?

Second issue is the choke cable seems a bit too long for the choke linkage. I’ve seen some carbs have a plastic bit at the linkage, I wonder if I’m missing that. Or something else?  I’ll try to post photos too.
« Last Edit: February 12, 2023, 02:02:06 PM by club_c »

Offline Don R

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Re: CB carb trickery
« Reply #1 on: February 15, 2023, 12:29:11 PM »
 Can you manually operate the accelerator pump? Often the accel pump squirter passages get plugged up. The choke cable housing needs pulled back somehow. I can't see the bracket in the pic. Some of them have adjustment at the knob end too.
« Last Edit: February 15, 2023, 12:31:38 PM by Don R »
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Offline MauiK3

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Re: CB carb trickery
« Reply #2 on: February 15, 2023, 01:53:59 PM »
Hard to see what’s going on with the cable.
1973 CB 750 K3
10/72 build Z1 Kawasaki