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76 cb750k "bogs out" during strong acceleration

Christian1791

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Hoping for some advice.
I have a 1976 cb750k. I recently rebuilt the carbs (new gaskets, o-rings, needles etc.) 25 total miles on the rebuilt engine/carbs.
Right now I'm running 120 jets, needles are on mid setting, K&N Air Filter Pods - (48mm/1-7/8"), 4 into 1 exhaust with 2.50" Cone/Reverse Cone Slip-On Mufflers 12".

I sync'd the carbs using carb sec gauges. Idles and runs great until I try to accelerate quickly (in all gears) the engine bogs out with a little bit of sputtering.
Accelerates fine when taking it K&Npods.jpgDSCF1284_1024x1024.jpg easy but as soon as I get on it, bogs out.

What should I be looking at? Too rich? Too lean?
I also getting a bit of white smoke out of the exhaust at acceleration.

I would appreciate any suggestions!
Thanks!!!
 
Could be either to rich or too lean. Have you taken a look at the plugs? Did it do this before the carb rebuild? These carbs dont like very fast openings because there is no accelerator pump. Its probably going lean on a fast throttle opening.
 
Could be either to rich or too lean. Have you taken a look at the plugs? Did it do this before the carb rebuild? These carbs dont like very fast openings because there is no accelerator pump. Its probably going lean on a fast throttle opening.

Thanks dirtdigger;
The bike wasn't running when I bought it. It was a complete frame up restoration.

After a ride tonight I noticed that it would "sputter/bog down" at first then catch up at higher RPMs in every gear.
I only have 80 miles on the engine and carbs after the restoration.

Thanks, it's good to know the carbs "don't like very fast openings because there is no accelerator pump". It just seems I should have more kick or power in the low end of each gear.

Tomorrow I'll pull the plugs and check for signs of running lean or rich.

Thanks!
 
Mine acted kinda like that. Had to adjust my needles to enrichen it some and it went away. But only plug chops will tell you whats really going on
 
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