Recently had the carbs rebuilt, now the throttle cable has no slack.

[ff255away]

I've tried adjusting the idle screw and have already adjusted the nut by the handle out as far as it can go at the handle. Can't get any slack on the throttle grip, and in order to connect the cable to the carbs I had to push the throttle lever up to meet the cable- I understand this could be apart of the problem but have no idea how to go about fixing it (besides detaching the cable, but then no throttle control...). At the moment, its idling at around 8k rpm on a cold start, no choke engaged.

If you have any input or could use pictures of something specific, let me know and I'm happy to take requests.

[bikerphil]

Turn out the main idle adjustment knob, on the bottom front between carbs 2 + 3.

[fredintoon]

I've tried adjusting the idle screw and have already adjusted the nut by the handle out as far as it can go at the handle. Can't get any slack on the throttle grip, and in order to connect the cable to the carbs I had to push the throttle lever up to meet the cable- I understand this could be apart of the problem but have no idea how to go about fixing it (besides detaching the cable, but then no throttle control...). At the moment, its idling at around 8k rpm on a cold start, no choke engaged. - - -

Hi ff and welcome,
adjusting the throttle cable adjuster nut OUT lengthens the cable's outer sheath which effectively SHORTENS the inner cable.
Try adjusting the nut all the way IN and see if the slack comes back.
If it don't, take the tank off and check the cable run to see if it's hung up somewhere or if the cable's outer sheath isn't stuck on the edge of it's location rather than fully within it.

[GLoweVA]

+1 on what Fred said, but also check that the bracket that the throttle cable goes into the carb bank (on top of the #3 diaphram cover) is in there correctly and that the cable sits into the little cup correctly. If the cable is cocked in there then that could use more cable slack.
Another thing to check is to make sure the cable end is properly inserted into the carb holder and swivels like it should.
I once put my carbs back in and that cable end bound up in there and wouldn't swing/swivel right and used up some of my slack.
I wish I had some pics to show you.

[ff255away]

Thanks for the advice, everybody. The solution ended up being disconnecting the cable from the throttle grip, and readjusting things from there. Basically, things were stretching the wrong direction and its a stupid issue that could have been prevented by disassembling the grip assembly.