Just bought a 1985 one owner gs with the 12a in it. Great compression, great start up, but slower than heck. I suspect that the secondaries in the Nikki carb are not opening as they should or at all. I've been researching and learned that it could be a whole bunch of things and that most people just mod the carb so that the secondaries are manual. I really don't want to do that unless I have to. I know that the secondaries are vacuum operated but for the life of me I can not seem to locate anything that tells me the vacuum source that actually opens them. I want to test that first. I know that it could be a faulty diaphragm in the secondary diaphragm assembly, but what operates that assembly? I know it's vacuum, but what is the source of that vacuum? Thanks in advance.

 

Check the teeter totter thing. Some call it the emergency return spring. If it slipped off, it can prevent the secondaries from opening. This happens sometimes when someone bumps the carb with a tool or their hand right on the teeter totter thing enough to cause it to slip off.

It is actually there to stabilize the end of a really long throttle shaft that has a ton of factory added crap on it.

 

Thanks Jeff20B. Upon further searching, you are right. Cant wait to get back home and hook this up properly. I know its off because I was looking at it last night thinking,..."Hmmm, looks like this is unhooked." Duh.

 

can anyone explain the 'teeter todd' thing...I was in there today and I note the shaft on the carb....lots of things look "unhooked up"....lol..

 

the 'secondary' will not open unless the 'primary' is opened as well..mechanically blocked, unless I actuate from the firewall side and then I can move it from the bumper side...takes 2 hands.... is this correct?
thx.