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New 750K guy

Posted by chuck hahn on May 01, 2018; 2:38am
URL: http://vintage-and-classic-hondas.81.s1.nabble.com/New-750K-guy-tp4063270.html

Got a 79 CB750K and have been working on it a while.   Did the maintenance per a service manual I got . The manual is a Clymer manual by the way.  All the valves shims are within spec, I disassembled the carbs and did a 24 dip in berrymans carb sauce.  I also used the Morgan carb tune to sync the carbs.

It runs pretty darn good but i got a little problem accelerating.   Note this is while its running on the lift.   I am a bit confused on what mark i line up with the pointer at the top of the case.  I found a picture from google of the timing setup this bike has.   I currently have the pointer lined up with the right line of the double lines with the "S" to the left and the "F" underneath the double lines.

I thought this was the correct line which leads me to the problem.  If I roll the throttle on kinda easy..not a quick full throttle twist..it rev up nice and will go to 8,000 RPM smooth and easy.  Now the problem is that if I twist it real quick it wants to hesitate a bit and isnt as smooth and reactive like when i just easily roll on the throttle.   Am I making making sense trying to accurately describe whats going on??

If i have the pointer lined up right, my next thought was to bend the arm that pushes on the accelerator pump so thre is more of a gap.  My thinking was that maybe the accellerator pump is getting involved too early and kinda flooding the engine.

Think I should revisit the carb tune again and try resyncing the carbs yet again??   Ive worked on more than a few bikes but this Honda has got me fresh out of ideas where to check.