Rubber plugs for the carb

[Crazcnuk]

Yes, but so far no one has come up with ANY of the XS carbs that actually need them. I can't see putting parts in the kits that aren't used for any of the carbs.

[81xsproject]

Ah HAH!

I couldn't take it anymore. This question was driving me CRAZY! So, I pulled the carbs out of the box and opened 'um up. I think this should satisfy all the non-believers

These are the 1980 G model carbs with the brass floats.



You can plainly see the hole going to the pilot tower with the help of some lighting.

[fredintoon]

Hi '81,
so, Gs got brass floats and a cross-drill into the main jet passage and need those plugs or she'll run rich, OK.
BUT SGs got plastic floats and no cross-drill and if you put the plugs in you starve the pilot jet so she'll hardly run at all except wide open.
Glad that's cleared up.
One question remains:-
WHY'D THEY DO THAT?

[81xsproject]

Or, maybe a better question, other than county differences and BS34I vs. BS34II, why the hell did the make so many, SO different on bikes that have almost everything else the same? Cam and head changes correspond with the change from the BS34I to BS34II carbs. Yet the variety in internal carb components, ie main jet size and their variation between inner and out cylinders, pilots, jet needles, emulsion tubes, etc., is different between nearly all the models. The only non-carb difference I can think of is timing.

[Crazcnuk]

Then, if that's the case, that would explain why mine was running so rich at the stock float level. I compensated by raising the float level, but it still doesn't get that great of fuel mileage (right around 30mpCDNg).

So now, I should take the carbs off and put those plugs in?

I think I lost two of the plugs though....

[81xsproject]

Obviously check and confirm that you too have the port drilled between the two. Good thing is you can get just the plugs from mikes as well.

[Crazcnuk]

I will definately check.

Bad parts about Mike's is the shipping.

[81xsproject]

Good ol' cycle recycle has them too. $2.50 each. Listed for the 80-83 xs650. No pic though.

[boyat68]

On my 80 carbs I have the rubber plug that is on the Pilot Tube, it is held in place by a short tower part made into the bottom of the float bowl. I suspect that the plug is necessary to force fuel through the passage from the Main Tower to the Pilot Tower as evidenced in the posted picture above by 81xsproject. I left mine in because they were there. My floats are the plastic type and I assume that they were original. I questioned that they were not brass as shown in the Clymer chapter 6 but in the supplement page 254, they are shown as the plastic type.

[Crazcnuk]

My 80 carbs have teh plastic floats, too, that is one of thes reasons I was questioning the plug issue.

My carbs did not have any plugs in them, but the carbs had been apart before and otherpieces were not where they were supposed to be either.

[Crazcnuk]

Ok, it's spring, took mine apart, again.

80G, plastic floats, NO crossdrill in the main tower. The carbs have a little step machined where the plugs would go, and there are little tabs in the bottom of the float bowls to hold the plugs in place.

Float level set way lower than spec.

Runs rich enough to make people's eyes water at normal highway speeds.

Best fuel economy, so far, about 30mpg (Imp gal).

[planedick]

Floats...

Set floats higher (less fuel in bowl) it will make it run leaner and get better mileage.

[Crazcnuk]

The floats are set so that the fuel is lower in the bowl, sorry, got that backwards.

Doesn't matter now, anyway. My carb(s) are screwed.

When I rebuilt them last year, I had one idle mixture screw that was siezed in it's bore and the PO had stripped the screw slot out of it trying to adjust it, or get it out.

I bought 4 new sets of idle mixture screws, and today tried to get the old ones out.

Out of the 4, two came out easily, one I had to drill out and the 4th wouldn't even come out with a drill. I got 3 little washers, 2 1/4 little orings, 4 springs and one screwed carb.

The one that wouldn't drill out (reverse drill bits/easy out combo) I drilled large and larger until the next bit will take out the threads, but there is still a nice layer of brass welded into the threads, that I can't get out. I did get the needle portion and spring out. but I have no way to put the new assy in.

The two outer carbs didn't appear to have washers or orings in there, but I got 1/4 of an old oring out of the one furthest from the choke lever, and none out of the one closest to the choke lever.

The two center carbs had all the proper pieces. Although I ended up with 3 washers, I didn't see any washers come out of either of the two outer carbs...

I did break the tip off of one of my picks, that I used to get the oring/washer combos out of thier slots.

So unless I can find at least one carb, I am out of luck for a while.

[planedick]

Carbs...

I have a bank of donar carbs that might help. Couple of the slides are stuck, but lots of good parts. Since I have a complete set of spares in good condition I would donate for shipping cost.... Not sure there are any jets so let me know what you need besides bodies as I have a rather extensive collection of most peices.

[Crazcnuk]

All I really need isd the body itself. I put all new float valve assy's and gave them a good clean last fall. That's when the rubber plug question came up.

That's also when I found that one has a stripped out idle mixture screw.

I think that once the emission caps were taken off, moisture and dirt collected in the holes on top of the idle mixture screws they started to weld themselves in.

I think, if they will fit snugly, I'll use the extra set of rubber plugs I have to cover those holes after I get it all tuned.

When I first took the carbs off the bike, some of the jets were loose inside the float bowls, so who knows what all was wrong with these carbs before I got them.

Are your carbs also from an 80G?