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Setting the Accelerator Pump

TequilaSqueela

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The bike dies when giving it throttle and I have been working through the carbs and the FSM. Set my float height and went to do the measurements for the accelerator pump. The rod rests on the control arm when the spring is out. With the spring in it is 0.5mm from the arm. When opening full throttle the arm stops just short of contacting the pump rod bottoming out on the idle adjustment housing notch. The book says to “bend the adjustment arm” to get between 0 and 0.4mm clearance between the rod and the arm. It then says to measure the gap between the control arm and the idle screw housing stop. This is a 79 and I’m not sure if it is an issue with the rod spring, the adjustment, or both. This is a rebuild kit. The old diaphragm was shredded.

The picture is black and O have read elsewhere to never touch the accelerator pump adjustment, but that was for the SOHC so I’m not sure.

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All the pump rods on DOHC 750-1100 are supposed to be the same. Likely cheap crap Chinese kit with too short a pump rod. Simply bend the tab above it down slightly until it barely touches. You can always bend it back up if the rod gets changed again later.

I do zero clearance, not even the .4 mm. You want the pump active wit6h the slightest movement of the throttle. I would cycle the throttle to wide open to make you you don't hit or bind the rod at max open. You should be able to tell by watching the spring.
 
So it turns out I had the spring on the wrong side of the diaphragm which I only checked after bending the arm. With spring on the right side it actually sits where it should. But now the arm doesn’t bend back. Looks like I’ll have to dear down the whole thing to bend it backwards.
 
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