Author Topic: Need advice  (Read 610 times)

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jtrain

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Need advice
« on: March 22, 2008, 11:26:02 AM »
how far will I have to tear down carbs on a 79 cb650 to clean air and fuel passages. This bike sat about 5 years before I got it. It would run what seemed to me ok but only with the choke all the way on. I have the carbs off now and dont want to take them off a third time. Any input would be appriciated. Hope to hear back soon. thanks

Offline TwoTired

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Re: Need advice
« Reply #1 on: March 22, 2008, 11:54:11 AM »
You have to tear down to where the fuel level in the carbs were at, when it evaporated and left deposits.  The float bowls are usually filled just below the gasket surface where they mate.  Any part of the carb immersed in the fuel will likely need attention.

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Lloyd... (SOHC4 #11 Original Mail List)
72 500, 74 550, 75 550K, 75 550F, 76 550F, 77 550F X2, 78 550K, 77 750F X2, 78 750F, 79CX500, 85 700SC, GL1100

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Offline eurban

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Re: Need advice
« Reply #2 on: March 22, 2008, 12:17:28 PM »
Once the assembly is removed, I rarely break down the carb rack unless things are an absolute mess.  Basically I remove all the covers, slides, jets (pressed in pilots removed of course) etc etc, but keep the carb bodies together.  The individual parts are soaked in carb / parts dip where appropriate.  Since there are still some rubber bits on the rack assembly, particularly the interconnecting fuel lines and the lines for the accelerator pump, carb dip is not appropriate for the rack. The entire rack can safely go in hot Simple Green bath and then get washed off / out with spray carb cleaner and compressed air.  This method avoids messing with the throttle and choke linkages and works pretty well for most carb sets. . . . Pay extra close attention to cleaning out all passage ways, and soaking and clearing the idle jets.  Run a single strand of copper wire thru the idle jets to confirm that thet are clear.  Bench synchronize the carbs, and if you like, check the level of fuel in the bowls using clear tubing on the overflow nubs.  Once the carbs are fueled up, visually confirm (on bike, airbox removed or carbs on bench with fuel in bowls)  the operation of the acell pump (if so equiped) by whacking open thottle while looking for fuel squirting out of the brass nozzles located at the bottom of the carb bore near the choke plate.