Detailed '82 Carb pics/diagram

[rbmgf7]

Hi, new guy here and just aquired a used Maxim. Looks good but only problem so far is that the previous owner decided to explode the carbs down to every last nut and bolt and mix it with a second set of carbs. It wouldn't be as hard if he hadn't taken the carbs off the rail. I have a maintenance guide with a diagram but it seems like it's missing a few things.

i know i'm short fuel rails. did these carbs share a singe rail or did 1-2 and 3-4 have seperate fuel lines in? I noticed there are also ports, with same size diameter holes as the fuel line in, which lead to the bowl. any reason for this or is it suppose to be plugged (this port faces between 1-2 and 3-4)?

i also noticed i have 2 different models of carbs; both are mukini CV's. one appears you have the ability to adjust A/F idle and vacuum ports while the other has plugs (or it appears it came casted like that). Thanks, ray

[81xsproject]

1-2 and 3-4 had their own fuel T's. The higher ports into the bowls are just bowl vents, don't plug them. Run hoses up and out of the way. If the carbs you are using have the plugs you will want to drill those out CAREFULLY. Otherwise, you will screw up the mixture screws.

[rbmgf7]

thanks. i just happened to find a diagram of the fuel lines in another thread.

another thing i just noticed about the two carbs. one is spaced wider then the other. the narrower one i started to get assembled is the Maxim's carbs as it sets flush with the carb holders. the 1-2 and 3-4 are spaced the same on both but the other one is wider between the two banks of carbs. i've searched and found out there were a few different version carbs but nothing on spacing.

[mro]

78 and 79' used BS34 II and 80'+ used BS34 III carbs.
If the float needle seat screws in they are the earlier carbs and will have the vent tube/port as 81xsproject mentioned. Several other differences between the two.

BS34 III's had the pilot screws "pluged". I drill small hole just thru it then screw in a sheet metal to pull em off. There should be at least 3/16 of an inch between plug and top of pilot screw.

There's about a 1/4" wider gap between #2 and #3 carbs.


mro
BTW, if the PO was a little ham fisted... check the ends of your pilot screws. I have found the points broken off and stuck in the carb.

Welcome to XS land

[81xsproject]

Also, I should have mentioned that so long as they are 80's carbs, I have lots of spare parts. So, if you are missing anything let me know.

[rbmgf7]

ok, so i'm having a little confusion as to which fuel tee goes where.



pic'd are 4 tees, two small, one med. and a large and two straight.

is this right? i get the feeling that it is not. i can't find any close up pics of these carbs.

(below) is carb #4 on the left and #3 on the right. on #4, i used a small Tee on top and a straigh on the bottom (same for the other carb)


(below) is carb #3 on the left and #2 on the right. the medium tee which you can barely make out is the fuel-in? i know earlier i asked and it was said these carbs have fuel-in belween 1-2 and 3-4. i just want to make sure the PO didn't jack it all up and make something up that he thought was OK. so i have a large tee for...

[trbig]

Just so you know... the XJ carbs don't have a vent at the top like was stated. All you have is the fuel "T"'s between each 2 sets. If you find a set that has the opening for the vents above those, it isn't the XJ carbs, and probably from the other set. If you find 4 neoprene floats, I would use those over the brass ones. The brass ones can leak.
The XJ also came with 112.5 main jets and the pilot jets were 47.5. If you look at the edge of the bowls themselves, there is a small brass jet down in the bottom of the hole in the lip of the bowl. This is the enrichener (Choke) jet and need to make sure this is clear and clean.

Since you are already able to post pics... you are WAY ahead of the norm here.. lol. Good luck.

Tod

[cruiser]

Maybe some pics of my xjcarbs will help in your assembly.

[TopCatGr58]

Hey there Ray,

In the LINKS section you'll find a thread about the ONLINE Yamaha parts fiche that you can use to see exploded views of any part of the bike. Oh well, I just supplied it below.

Yamaha Online Parts site

Okay, the carbs you showed in the last 2 photos appear to be the XJ, they have the press in float needle seat...uses that little "U" shaped flange and screw to hold it in place....needs a NEW O-ring....is one place where they like to leak if not replaced, as well as the float needle itself.

The carb bodies HAVE the recesses for the older upper "T"'s, but in the later model carbs they are BLOCKED OFF. The lower openings closest to the bowl is the fuel inlet. Those straight silver colored fittings may be just stabilizers to help keep the bodies in position by placing them in the upper body holes, but they are not shown in the parts fiche. I've not worked on XJ carbs exactly, but I'm pretty sure that about the only difference is the use of the REMOTE fuel enrichener/choke lever.

Also, I noticed that you have the rubber pilot jet tower caps in place, and they are NOT used in the later model carbs! The earlier 78-79 carbs used them because they shared the fuel supply with the MAINS thru a tunnel between the towers, but the 80-82 carbs pilots get their fuel directly from the bowl, so you DON'T want to cap them off!
Good Luck.
T.C.

[81xsproject]

Are you sure both sets are xs/xj carbs? None of the xs/xj had those straight joints. It looks to me like at least one of your carb banks was a single inlet set and I would guess that on that set (whatever it was off of) the straight connectors went between 1-2 and 3-4 with that very large/wide T between 2-3. Suki's had that on their BS34's. They also had a wider gap between 2-3 carbs.

[81xsproject]

That's not totally true, TC. If they are 1980 carbs, they MIGHT need the rubber plugs.

[81xsproject]

Oh yeah, I think your medium T is the one you need 2 of. If you can't get one, let me know, I have some old ones. However, I can't swear that they will seal.

[rbmgf7]

thanks for the help. i kinda fiugred it out and went ahead and installed them. the bike fired and turned over with a little ether but the carbs wouldn't catch unless i placed my hand over the intake. i'll figure it out later.

i'm just going to clean up and touch up this bike the turn around and sell it. i really don't intend on keeping it. 1100cc's is way to much bike for me. i currently ride a sohc cb750 and that's good enough for me. however, i'm a fan of the XS650. those can make some pretty sweet cafe bikes.

heres a pic of the XJ


came with a vetter