Topic: 77/78 750 carb/choke questions

[Lumbee]

...sup ya'll, I'm trying to take advantage of the mild temps in the dirty south and ride my bike to work some. Its a little chilly in the morning, and I'm running into 2 problems before leaving for work:

#1-With full choke the bike (78 750 SS) barley gets above 1200 RPM or so...I'd like this to be a little higher.  How can I adjust this?

#2-My choke won't stay on.  I have to hold it up with my hand or else it falls down/closed.  Is there a way to tighten something up so there is more resistance on the cable or choke arm and the choke will stay open?

[Joe Danger]

My choke vibrates its way back down when it's out, I have to hold it.  (77 550K).  Seems like if I don't lube it it's better, but when it's properly lubed, it's a very manual choke.

[Lumbee]

...yea, the choke was sticky when I first got the bike.  Being a newbie I lubed the heck out of all the cables...now I wish I would not have lubed it.  Maybe I should bury it in the ground for a week and see if that helps...

[theunrulychef]

You can tighten the rubber piece that the choke control sits on - directly under the "button" of the choke - that will help it to stay up on it's own. 

As far as resetting the choke RPM, trace the cable back to the linkage on the carbs.  There's a tiny screw that you can use to modify the RPMs.  It holds the throttle a little further out than normal.  Once you get in there with the tank off, you should be able to see how it works.  Just don't move it too much or it won't work right.  Try it in small increments first.

[Lumbee]

..ahh    I know the screw you speak of...I wondered what that did.  So it just slightly turns the idle up when the choke is pulled.  Excellent!

As far as he screw under the choke button, I tightened it up last night, and it didn't seem to do much good...I fiddle with it some this evening...good info...thanx...

[damn_yankee]

The choke knob can be tightened by turning the cylindrical piece right below the knob (on my K8).

To adjust the rpm you'll need to take the tank off. There's a small screw that contacts a cam on the choke cable mechanism. You adjust it until it touches the cam with the choke on and then turn the screw one more time or until you get the desired rpm.

Good Luck

[eldar]

If your choke knob does not stay up after trying to tighten it, then you need to get a new choke cable if you want it to stay where you put it. That knob just controls the amount of friction placed on the choke knob shaft by 4 small plastic tabs. They do wear out and only replacing the cable will really take care of it.

[scondon]

   If your idle isn't increasing when you pull the choke knob all the way up it may be that the cable has slipped or is set too low. There is a small clamp that holds the cable just above the activating arm (middle rear of the carbs) and if the cable is not set correctly in this clamp then the choke will not work properly. On my carbs, the idle speed doesn't begin to rise until the choke is more than half way engaged.

[Lumbee]

...I pulled the tank and checked everything out tonight...no way could I get my hand down to the spot where that set screw is at to increase the idle...I'll have to wait til I pull the carbs off again to get to it.  I tightened the bolts around the top of the choke to no avail.  I guess the plastic is just wore out.  I stuffed some wire in that crevice and this offered some resistance, so we'll see how that works out...