Back at it again... Carbs to lean (1980)

[NewestOnTheBlock]

The floats in your pic are from "older" VM series carbs. they slid up and down on posts they don't pivot.

I'll go shoot up a BS34 foam float be back in a bit.

Right. The photo was more to represent what the float "ends" look like....just rounded. They are connected to a metal piece that does pivot.

 

[5twins]

If you can't set your floats, you can't tune your carbs, plain and simple. It's nice to see you're trying, but you aren't there yet. I don't know what else to say besides what me and Griz put in the Carb Guide. It's all there, or on the board here. You guys still continue to butcher your carbs and bikes anyway. I pretty much have given up trying to help. You remind me of one of my favorite one (or two) liners ..... "Hire the handi-capped - they're fun to watch ...."

 

[NewestOnTheBlock]

No I hear you. The guide and the chylmer book are both very helpful, combined with the help for this forum and I would be set. The problem is I keep coming across random issues that aren't addressed, or shouldn't be there. In this case, its floats that aren't suppose to be in there.

 

[5twins]

The brass floats from 1980 and the later plastic floats can be swapped. You just have to set them to their spec. The brass and plastic have different ones. You also have to measure correctly, to the right spot on the float. I know all this stuff, I've posted it numerous times, I'm tired of doing so, you could find it I think with a search. (3 pages and you're still lost ... this doesn't bode well for your motorcycle mechanic skills, lol, or your internet ones either)

 

[gggGary]

Yes those are the right floats.
I did have some better BS34 float pics but my damned close focus on this camera sucks.

These off a random old set of carbs I just opened are set "about right". Note slight angle compared to the carb base.







Gotta go stir the stew, it's snowing here again, damnit!

 

[NewestOnTheBlock]

Much thanks gggary. Since I can't find any photo reference of mine, i'll try to borrow a friends and take a photo soon.

My floats ends (the actual black, end pieces) are completely round. And I believe the difficulty with why I can't get them lowered down to 22mm, is that they attach to the metal bracket in the middle. As opposed to your photo, where there is the metal bracket, then the black floats move away from the pivot point (kind of where the black is squared off), and then the rounded piece is formed...........so your metal pivot bracket is essentially above (even though the carb is upside down, but referencing your photo) the majority of the black floats.

While my metal bracket, just connects right in the middle.....right in half........literally if you we're to cut it right where the metal bracket piece connects to, you would get 2 equally rounded halves.

Like I said, I'll try to get a buddies camera soon.

 

[gggGary]

A very nice pic from oldskkool

By the way this thread is a great read, skim til you get to page 4 for some "truth" at long last. A typical we can't SEE what you are doing (and especially NOT doing) long distance trouble shoot. And a rare MIA culpa from the OP'r

 

[gggGary]

We have not seen your carbs, we don't even KNOW they are BS34s..........
I swear I have seen about everything but an updraft tractor carb stuck on a "runs good" XS650.

And that's probably been done too.

 

[5twins]

It sounds like you may not have original floats, or maybe not even original carbs. Like Gary said, we need pics. If we could read minds, we wouldn't be here asking stupid questions. If my dick was longer I'd be a porn star and not fucking around on some Jap bike forum (but it would need to be lots longer, lol). Anyway, I have a dream(sicle). (I just loved that guy's avatar by the way, lol. It's not that I'm prejudice or anything, .... but I am).

 

[gggGary]

Wait I almost got it here's a Ford carb install..........

TeeCat has this running well.....

View attachment 4774

 

[5twins]

Years ago, the then current mechanic at my local bike shop was working on his Harley carb. Honest to God, it wasn't much more than a brass tube with holes in the side. I asked him what tractor that came off of. He took offense .... "that's off my Harley ...." he said. I still laugh about that one ... the best 1945 motorcycle made today, lol.

 

[NewestOnTheBlock]

So I dug out my old camera.....if i'm doing this right, photos should be displayed...if not, the photo links should show up.

 

[Gordon]

Now you might want to really 'clean' the pilot system. It is even smaller than the idle circut. An it DOES get clogged up. Very common on the BS34 carbs.

Nope, no photo's.

 

[gggGary]

Well they sure look like BS34 carbs. No idea about those floats though........ Some aftermarket replacement float? BS34's were used on lots of different Japanese bikes not just XS650's but they are all a little different would be nice to see some other angles so we can tell if they (probably) are XS650 carbs, the crossover fuel feed tee looks XS. So you will have to use the tube method to set them. Typically a drilled out 90 degree zerk fitting in the drain hole then clear plastic tube. You also need to be sure they aren't binding anywhere. Have you removed the rubber caps and OH SO CAREFULLY pulled and cleaned the pilot jets?
You'd better check that all the brass is genuine mikuni and has the correct part numbers/sizes.

 

[gggGary]

I'm guessing these are the floats.

The seller posted this cross reference

KZ1000-A1 KZ1000 1977
KZ1000-A2 KZ1000 1978
KZ1000-A2A KZ1000 1978
KZ1000-A3 KZ1000 1979
KZ1000-A3A KZ1000 1979
KZ1000-A4 KZ1000 1980
KZ1000-B1 KZ1000 LTD 1977
KZ1000-B2 KZ1000 LTD 1978
KZ1000-B3 KZ1000 LTD 1979
KZ1000-B4 LTD 1980
KZ1000-C1 Police 1000 1978
KZ1000-C1A Police 1000 1978
KZ1000-C2 Police 1000 1979
KZ1000-C3 Police 1000 1980
KZ1000-C4 Police 1000 1981
KZ1000-D1 Z1R 1978
KZ1000-D3 Z1R 1980
KZ1000-E1 Shaft 1979
KZ1000-E2 Shaft 1980
KZ650-B1 1977
KZ650-B2 1978
KZ650-B2A 1978
KZ650-B3 1979
KZ650-C1 Custom 1977
KZ650-C2 Custom 1978
KZ650-C3 Custom 1979
KZ650-D1 SR 1978
KZ650-D1A SR 1978
KZ650-D2 SR 1979
KZ650-E1 LTD 1980
KZ650-F1 1980
KZ650-H1 CSR 1981
KZ650-H2 CSR 1982
KZ650-H3 CSR 1983
KZ900-A4 1976
KZ900-A5 1977
KZ900-B1 LTD 1976


Suzuki
GS1000C 1978
GS1000C 1979
GS1000EC 1978
GS1000EC 1979
GS1000EN 1978
GS1000EN 1979
GS1000L 1979
GS1000N 1978
GS1000N 1979
GS1000S 1979
GS550E 1977
GS550E 1978
GS550E 1979
GS550L 1979
GS750B 1977
GS750B 1978
GS750B 1979
GS750C 1977
GS750C 1978
GS750C 1979
GS750EC 1977
GS750EC 1978
GS750EC 1979
GS750EN 1977
GS750EN 1978
GS750EN 1979
GS750L 1979
GS750N 1977
GS750N 1978
GS750N 1979
GS850G 1979

The problem is still knowing what is a "correct" float level in this application. The clear tube method is the only reliable method to get it right and watch for binding anywhere in the float travel.

 

[NewestOnTheBlock]

Well they sure look like BS34 carbs. No idea about those floats though........ Some aftermarket replacement float? BS34's were used on lots of different Japanese bikes not just XS650's but they are all a little different would be nice to see some other angles so we can tell if they (probably) are XS650 carbs, the crossover fuel feed tee looks XS. So you will have to use the tube method to set them. Typically a drilled out 90 degree zerk fitting in the drain hole then clear plastic tube. You also need to be sure they aren't binding anywhere. Have you removed the rubber caps and OH SO CAREFULLY pulled and cleaned the pilot jets?
You'd better check that all the brass is genuine mikuni and has the correct part numbers/sizes.

Everything other than the floats appear to be stock. I have absolutely cleaned the carb thoroughly, pilot jets and all. rubber caps and carb plunger as well. all per manual/clymer book.

I'm guessing these are the floats.

The seller posted this cross reference

The problem is still knowing what is a "correct" float level in this application. The clear tube method is the only reliable method to get it right and watch for binding anywhere in the float travel.

Very impressed, I couldn't find those at all.

Right. My debate right now is whether or not I keep the floats....

-Reasons I WOULD keep the current floats..........only reason is that I know at one point that they have indeed worked on this bike. Fully functional.

-Reason I would NOT keep the current floats.......all documents refer to parts that are to be used with the xs650. As mentioned before, these current floats aren't in the measurement range, and almost feel more like a burden then anything else.......if anything, continuing to work on the bike would be simpler because I know I would be working within the specifications of the carb manual and clymer.

I'm leaning towards buying new/used floats....

 

[peanut]

just thinking out loud here.

if the po changed the floats might the needle valves be the wrong length as well ? I don't know if they were all the same length through the model /carb range or not ?

If you remove the needle valves altogether will the floats then sit down far enough that you could achieve a 22mm measurement ?
When adjusting the tang and float heights remeber not to put any undue pressure on the needle valves , the springs should be uncompressed not pressed down .

If your tangs end up at an acute angle relative to your needle valves ie not perpendicular the needle valves will be forced to one side of their chamber and rub and the friction might prevent them from functioning properly as happened on my 38's

You really need to borrow a camera from a neighbour to help us to help you. Sometimes a fault can be spotted from a picture that would otherwise not be apparent otherwise.

 

[NewestOnTheBlock]

just thinking out loud here.

if the po changed the floats might the needle valves be the wrong length as well ? I don't know if they were all the same length through the model /carb range or not ?

Very good idea. After tearing down the carb, I think I got a idea of how the previous owner was thinking. I could kind of see how he or she thought about things, you know, gain a generally feel. I wouldn't be surprised if the needle valves we're indeed different than stock. I have only taken the actual needle out, but taking both the needle and needle valve out might bring it down to the desired 22mm....

If you remove the needle valves altogether will the floats then sit down far enough that you could achieve a 22mm measurement ?
When adjusting the tang and float heights remeber not to put any undue pressure on the needle valves , the springs should be uncompressed not pressed down .

Very good idea. After tearing down the carb, I think I got a idea of how the previous owner was thinking. I could kind of see how he or she thought about things, you know, gain a generally feel. I wouldn't be surprised if the needle valves we're indeed different than stock. I have only taken the actual needle out, but taking both the needle and needle valve out might bring it down to the desired 22mm....

If your tangs end up at an acute angle relative to your needle valves ie not perpendicular the needle valves will be forced to one side of their chamber and rub and the friction might prevent them from functioning properly as happened on my 38's

Right. at a certain point the tangs just we're getting way to bent. Even though I never saw the floats I have on any other xs650, I could see how far bent the tangs were of others. At a certain point it was to much, almost defeating the purpose of them.....


I'll try to get some more pics.

 

[NewestOnTheBlock]

For some reason, I can't seem to post pics. But here are the direct links to some new photos of the carb itself.

http://picpaste.com/f8d9dc635b26ce608a9144a3a563fe4a.JPG

http://picpaste.com/2f0997765ddcba141dda212fde6242fc.JPG

http://picpaste.com/f9328ce74ee23edf83a750327f80cca1.JPG

http://picpaste.com/8b61f4ae99f570130d43841c6a1ff400.JPG

http://picpaste.com/63b2c1c8e6479335aa40944bb9d440a1.JPG

 

[NewestOnTheBlock]

Bump. would appreciate more insight...