Topic: carb rebuild and now choke plates sticking/hard to open

[yitzac1990]

Hello, I just rebuilt the carbs on my 1978 CB750K, got them all together (minus the slow jets, still waiting on those), and now the choke linkage/plates are sticking.  when I pull up on the choke linkage (as the cable would do when installed), the plates basically dont move, or move very slowly and very little.  any idea why this is happening?  Can anyone point me to some close up, detailed pictures of how the carbs assemble together in their "rack", specifically where the 2 choke linkages meet?  I tried searching, but couldn't find anything too detailed in that area, nor in the technical service manuals.

Thanks

[b52bombardier1]

Spray some oil on the choke shafts and work it. Mine did the same thing but are good now.

Rick

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[yitzac1990]

Ok ill give that a try later today.  Is it safe to say that over time they will "loosen up" as I run the carbs on the bike?

[flybox1]

If you removed the choke plates during your rebuild, its possible they are shifted slightly and hanging on the carb throat walls.
To fix this, partially loosen the 8 choke plate screws so they can 'self-adjust' within the throat of the carb.  Lift the choke so the plates close, center the plates, and then gently tighten the screws.
There should be no contact between the plate edges and the cab throat walls.

[machacc]

Mine were stiff after sitting for years also.  I had to spray lube them twice but they did loosen up and do work right now.  Ron

[madmtnmotors]

If you removed the choke plates during your rebuild, its possible they are shifted slightly and hanging on the carb throat walls.
To fix this, partially loosen the 8 choke plate screws so they can 'self-adjust' within the throat of the carb.  Lift the choke so the plates close, center the plates, and then gently tighten the screws.
There should be no contact between the plate edges and the cab throat walls.

+1

There is no direct connection between the choke linkage and the choke plate shafts. The shafts that the choke plates mount to are spring driven and are very sensitive to any drag and/or misalignment. flybox1 has described a good corrective action.

[yitzac1990]

got it guys.  i loosened up the 2 center plates and they instantly became free to move.  snugged the center plates back up and were good.  thanks all!!

[madmtnmotors]

got it guys.  i loosened up the 2 center plates and they instantly became free to move.  snugged the center plates back up and were good.  thanks all!!

Thanks for posting your resolution.    Too many resolve their issue and never come back. 

[flybox1]

Glad it was an easy fix! 

[yitzac1990]

Thanks for posting your resolution.    Too many resolve their issue and never come back. 

no problem, I know how it is....searching forums and someone has the same question, but no posted resolution!

on a side note, my work computer proxy blocks this forum and i cant do anything on here until I get home... so sad!