1972 CB350 Carb Issue

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jryftc

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So I'm helping a buddy re-do a 1972 CB350. Got it with one cylinder firing (left one) No spark in the right boot. Simple electrical error from the previous owner solved that. Put new plugs in, and made sure both bowls had fuel. At first the right bowl had no fuel, so I pulled the carb off. Sprayed carb cleaner throughout, seemed to fill up fine, however I noticed that the swing "valve" flap type thing that is goes with the choke on the right carb is cracked down the middle. I've attached a picture of the piece. It's that flap literally cracked.

Didn't try to fire the bike up on two cylinders, just left the right carb off, but does anyone know where that single piece can be ordered? Does it make sense to get a new set of identical carburetors? Hesitant on that...theoretically though, the bike should still fire, just run like shit because the right side is almost permanently choked, nah? What do you guys think?
 

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Also, these are how the carbs should look. It's that flap on the back that's shown here thats split in half.
 
After rereading I'm still not exactly sure what you're asking, and what's cracked. But I'll take a stab at it. Sounds like you have a crack in the choke plate. You should replace that ASAP as you run the risk of sucking something into your engine.

That being said, your other cylinder should fire with the choke off. Spraying carb cleaner around might not solve your fuel starvation issue --you've got a stuck float valve, your valves are getting caught up something, your fuel passage is blocked, or your overflow tubes have cracks in them.

Have you checked the condition of the diaphragms? Torn ones make it a bitch to get the bike running right.

To replace the choke plate buy a shitty set of parts carbs with a good choke plate and replace. If your diaphragms are shot, and you can't solve your fuel starvation issue, it's a roll of the dice. You can find decent carbs sometimes for somewhat cheap (under $100) with everything intact. Finding those diaphragms can prove tougher, although there are kits to replace the diaphragm yourself.
 
Sorry, I actually worded like shit. Bowl was full when i pulled the carb. Drain screw was clogged. Bowl fills, fuel shuts off, empties with screw now, etc. Diaphragms are 100% fine, and actually I have a website you can order them off for $40 for Honda CB Models like the 350, 360 if you need it. But yes, choke plate is fucked. Looking into replacing it off an old set of carbs. Thanks for the response.
 
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