Help with carb ID

[Aches n Pains]

Working on another '79 Special. Previous post at: http://www.xs11.com/forum/showthread...447#post315447

Two sets of carbs came disassembled in a box - sort of a puzzle.

I fitted up (not all bolted and parts in place) the best set (shown here). Just not sure if they are the right set.This picture is from the engine side - spacing between 2 and 3 seems excessive. Note that I have not put the choke parts, etc. back on.



Plate on top of the carbs that carries the throttle cable is too small to bridge between 2 and 3.




This picture is from the airbox side of the carbs. There are two brackets connecting all four carbs (my other sets only have one). Carbs are tapped to mate with both brackets.



Picture from bottom of the carbs. Note second bracket.



A couple of other parts from the box.





Questions

Do these look like the carbs off a '79 Special?

If not, would they fit a '79 special?

What are the spare parts? Do they fit somewhere?



Thanks in advance for your help.

Aches n Pains (Doug)

[TADracer]

In a nutshell they do not look like 79 carbs. Possibly they are from another model year but I do not know which.

My 79 special carbs look similar but different. The syncronizing screw setup is different. The vacuum port on the #2 carb looks different. The towers that have the mixture screws look different and the choke parts you show are definately not from a 79.

Can they be made to fit? Sure, anything is possible but you are probably getting into a whole bunch of fitting and jetting considerations. Might be easier to try and pick up a rack-o-carbs for the correct model from someone on this site.

[crazy steve]

Hmmm, you've got a bit of a mish-mash there...

The carb bodies look like '80-81, the carb tops are '78-79, as are the float bowls. The hose nipple on number 2 carb is wrong too. The tie brackets that connect them don't look like any XS brackets I've seen (with that 1/2 moon cutout) so you may have a set off another bike. Your center-to-center distance on the carbs should be 3 1/16" between 1-2 and 3-4, and 3 1/4" between 2-3. If that's not what you have, these ain't XS carbs.

The BS34 carb was used on multiple bikes, but mounting/calibration wasn't the same so it's probably more trouble than it's worth to try to make these work...

[cywelchjr]

Hmmm, you've got a bit of a mish-mash there...

The carb bodies look like '80-81, the carb tops are '78-79, as are the float bowls. The hose nipple on number 2 carb is wrong too. The tie brackets that connect them don't look like any XS brackets I've seen (with that 1/2 moon cutout) so you may have a set off another bike. Your center-to-center distance on the carbs should be 3 1/16" between 1-2 and 3-4, and 3 1/4" between 2-3. If that's not what you have, these ain't XS carbs.

The BS34 carb was used on multiple bikes, but mounting/calibration wasn't the same so it's probably more trouble than it's worth to try to make these work...

Umm, right and wrong. The bowls are 1980 bowls, the bowls didn't change externally until 81, they are internally different in 80 though as they should have a protrusion to hold the rubber plug in the pilot jet hole when the bowls are in place which the 81 bowls don't have (this is only actually used if the cross passage exists but is there in either case), however your right I believe that the tops are incorrect for 80 being cast rather than stamped. The idle speed adjust is totally wrong for any year, as the early carbs would be on top and the late would be on the bottom but to the front.

The funny thing is, I'm not aware of any other bike from the era with a vacuum barb on the number 2 carb for vacuum advance like that. So even if not originally for our bikes, they may have already been modified for them.

[crazy steve]

..The bowls are 1980 bowls, the bowls didn't change externally until 81, they are internally different in 80 though as they should have a protrusion to hold the rubber plug in the pilot jet hole when the bowls are in place which the 81 bowls don't have (this is only actually used if the cross passage exists but is there in either case)...

Hmmm, yet another little weird item. The SG I'm in the process of reviving right now has the late-style bowls, and what's more, also has the 'bump' in the bottom of the bowl. Now, hard to say if the carbs are original (but the rest of the bike pretty much was), but I wouldn't be surprised if there's more than one style out there. Here's a pic of one...
[IMG][/IMG]
Or am I the only guy running into these strange parts? (I also ran into the different-dish rotors...)

It doesn't matter, as either bowl will work as long as you don't need the 'bump' for the rubber plug...

[Aches n Pains]

Thanks, guys.

I'll do some head scratchin and see if I can post any other useful pictures. Also possible I've mixed and matched parts from two sets of carbs.

[Rasputin]

Those sure look like a set I have in the garage. They are from a suzuki if they are. I will look when I get home from work and take a pic of them to compare.

[Rasputin]

These are off a Suzuki. They look a lot like our 11 carbs but do have differences. Note how the fuel line has but one barb.

[b.walker5]

... I believe that the tops are incorrect for 80 being cast rather than stamped.

Dont know about the rest of the carbs, never studied them close enough, but i can tell you that the tops on my carbs are cast, not stamped, and they're original 80's as far as I know.

[cywelchjr]

Dont know about the rest of the carbs, never studied them close enough, but i can tell you that the tops on my carbs are cast, not stamped, and they're original 80's as far as I know.

Just looked at mine again, which are original, and they are stamped not cast. Definitely a LOT of differences, they look a LOT more like those Suzuki carbs than Yamaha carbs.