Topic: Uh, yeah...that ain't right. CB650 accelerator pump rod

[Scott S]

 So, I'm working on a set of VB44A carbs from a CB650. The accelerator pump rod seems too short. It won't hit the actuator tab even at W.O.T. The diaphragm is bad, so I just ordered a new one, thinking maybe someone used the wrong diaphragm or something.

 Here's the old one. See how short it is? The gap is supposed to be  0.4-0.6mm.



 The new acc. diaphragm arrived today. Obviously, something ain't right. 




 I got it from http://www.motorcyclecarbs.com/ . I ordered the one listed for "ACCELERATOR PUMP DIAPHRAGM KIT: HONDA CB650 (1979-1982) ".


 Does anyone know the correct length for the rod? I can cut this one, I guess, but I hope the seller will make it right.

[Scott S]

 Well, now that I took the old rod out and actuated the linkage, the tab is where it needs to be and moves the old rod correctly....Hmmmm. I must have gotten something out of whack when cleaning the carbs.

 My options now:
 1) Contact MotorcycleCarbs.com and see what they say about the new rod, or..
 2) Cut the new rod and get these things back together.

[trueblue]

If the diaphragm is the same and only the rod is longer, I would just trim it to the correct length.  Remember to measure thrice and cut once .

[Tugboat]

Trim to correct length.

[jtb]

+1    Easier.

[Scott S]

 Chewed up pilot screws replaced, accelerator pump rod cut and new diaphragm installed. I also figured out why the tang for the accelerator pump rod was giving me fits....some numbskull had the spring on the wrong side of the diaphragm. Not me, though....NOooo, not me.... :oops:

 I also trimmed the tabs that kept the idle mixture screws from being adjustable. Set them all at 2.5 turns, but at least I can get full adjustment out of them now if need be. No more "EPA lilmiters".

 I'll probably check the sync on the bench, but the carbs look ready to go for now!