Topic: 78 CB750K Carbs

[Wingfever]

Newbie here guys,
I just made a rookie mistake.  Overhauled the carbs and remembered to take digital pictures but not until I had taken two of the carbs off the bracket.  I have it back together but I'm leary about the main spring.  My book and other pictures I've found are of the earlier carb setups.  The main issue I have is about the main spring.  It seems to be very tight the way I currently have it routed.  It may actually need to be that tight, but I just want to make sure.  Anyone have a picture of this setup?
I also noticed that the main jets, both original and the ones in the kits do not have the extra clip positions and the numbers do not match what I've read here and on other sites.  Any help would be greatly appreciated.

[eldar]

the main spring is tight. Many have griped about it on this forum. It gets hard on the wrist. So it is tight but should not be wound multiple times.

[Lumbee]

...ditto what elder said...I think its on a half or 3/4 turn around the throttle bar.

..on the jets, u'r talking the needles right?  How many clips does yours have?  And when u say numbers, do you mean numbers on the neelds themeselves?

[Wingfever]

Thanks for the spring info.  I guess I have that installed correctly then.  As for the needles, they just have the one groove for the spring clip and a number stamped near the top.  If I remember right, the old ones had a 15 stamp and the new maybe 13D.  I'm not at home now but I can check later for sure. I got the kits from Sirious off ebay so I assume these were standard kits. The bike has a 4/2 exhaust system with the standard breather air box.

[Lumbee]

...hey wing, I'm not sure what the deal on needle clips is.  I think I have a set of 77 or 78 carbs (not sure which) that does NOT have clips, but I have another that does.  All I can say for sure is that some of them do, unless the ones I have are not stock, and somebody added needles with the clip in it.

This is not really a show stopper for you, it just means you don't have the ability to lean or richen the mid- range.  You have to experiment with jets and go with what works.  If you have the the stock exhaust and airbox then I'd go with the standard 105 jetting, then read u'r plugs.

[eldar]

the 77 carbs had the slots on the needle. the 78s did not.

[BobbyR]

I went down and checked mine, and the spring is tight. Even with the push pull cable they want them to snap closed. If fact, it may be because it is push pull they wanted a lot of tension to move both cables. I used the Sirsonic kits also, but i kept my old jet since they were larger than the ones in the kit.