Author Topic: CB350F stalling if I open throttle too quickly from idle  (Read 1121 times)

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Offline fotodmick

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CB350F stalling if I open throttle too quickly from idle
« on: March 17, 2016, 05:46:21 PM »
I tried to search for this 6 ways from Sunday but no luck so I will start a thread. 

I have a 73 cb350f.  New coils and wires, carbs cleaned last fall. Was running great, I did lay it down back in february on a beautiful day we had here in Cinci.  Had to replace my steering stem but not that i have it up and running again I noticed that it doesn't like to come out of idle.  Starts fine, idles fine, screams on up to 10k just fine.  It is still almost unnoticeably bubbly around 4500-6000 when cruising but that is separate from this.  It won't stall when i am taking off from a stop because of easing into the throttle, but if I goose it in neutral from idle it will stall.  What am I looking for?

Cheers!

Offline drumstyx

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Re: CB350F stalling if I open throttle too quickly from idle
« Reply #1 on: March 17, 2016, 05:48:42 PM »
Is it warmed up completely when you do this? I have a bike that likes to be nice and warm before it's completely comfortable going all out from idle. Not a Honda, but still, I think that's a thing for carb'd bikes....they call it 'cold blooded' I think.

Offline fotodmick

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Re: CB350F stalling if I open throttle too quickly from idle
« Reply #2 on: March 17, 2016, 05:50:48 PM »
It does it cold, warm and hot

Offline whizzer

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Re: CB350F stalling if I open throttle too quickly from idle
« Reply #3 on: March 17, 2016, 06:18:24 PM »
Had this happen on cb350f after cleaning and sorting out carb settings. Hesitation when popping throttle. Before it would just rev like a dirt bike. What to do?   Loosened the clamps on all the carb boots and reseated them, ie, pushed on carbs a lot. Tightened clamps and got the quick rev back. Getting the old clamps tight takes care. Could be lots of things. But this fix was simple. Something to try first.
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Offline flybox1

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Re: CB350F stalling if I open throttle too quickly from idle
« Reply #4 on: March 17, 2016, 07:03:34 PM »
adjust your timing and advance?
was it able to handle a quick twist of the throttle before?  these are not FI bikes and usually act this way with a quick twist...
if your timing checks out, hyper-clean your carbs, and verify your fuel level is correct with the clear tube method.
« Last Edit: March 17, 2016, 07:09:22 PM by flybox1 »
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Offline Deltarider

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Re: CB350F stalling if I open throttle too quickly from idle
« Reply #5 on: March 18, 2016, 12:27:03 AM »
What are your airscrews set at? Slow jets should be 100% clean.
« Last Edit: March 18, 2016, 12:31:09 AM by Deltarider »
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Offline bochnak

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Re: CB350F stalling if I open throttle too quickly from idle
« Reply #6 on: March 18, 2016, 09:48:45 AM »
I can make any bike die in this manner. Is this a new problem for you? How quickly are you opening the throttle? What is your idle set to?

If it does not bog during a "launch" then maybe it is nothing to worry about.

Offline camelman

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Re: CB350F stalling if I open throttle too quickly from idle
« Reply #7 on: March 18, 2016, 06:39:22 PM »
If it was running well before the fall, then might not hurt to check carb sync and airscrew settings. Those air screws can work themselves loose in my experience if the little black caps are missing.
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