Boorrrringggg Build/Rebuild/Refres&restore

[3Phase]

The BS-34 and the 73 molded into the diaphragms shows they're for the '80 to '82 BS-34III with 73mm slides and I'm assuming that you didn't have to chimp out to get it to fit over the slide and put it back into the carburetor with the cover.

One week later....

[...]


3. reassembled, top view.

Carburetor slide Tech Tip:-
http://www.xs11.com/forum/showthread.php?t=33250

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[puskrat]

You have the right diaphragms. I don't recommend messing with them (ie removing from the slide) if there isn't a problem or you're risking damaging an expensive part. Those are aftermarket from JBM Industries (http://www.jbmindustries.com) and they require the plastic ring to be cut off. They have the thick donut instead of the plastic retainer. It's important that you put the slides back in facing the correct direction because there isn't a notch in the diaphragms. The hole in the slide needs to facing the engine side.

Edit: BTW, I put those diaphragms in my '81SH and they are high quality and will continue to use them in the future.

Thanks Pro. The diaphrams look heavier duty than the pix I see in the diaphram thread (I think that was kat's). All other things being equal, that should make them more durable, but not if they don't fit. Thanks for the reassurance, but I see another post indicates they're for a different model carb. I'd rather go with your take, since you've btdt. Have to consider all possibilities I guess. And yes, the plastic rings were absent. Need to look things over better.....hadnt noticed hole in slide.

[puskrat]

Next question: There are no screws. What does this mean?

[Prothec]

Next question: There are no screws. What does this mean?

You're screwed... no really, what screws where?

[puskrat]

these screws. photo from carb cleaning 101

http://i121.photobucket.com/albums/o...ningfun009.jpg

[puskrat]

the arrows are not pointing at the screws
screws are in slides

[Prothec]

Ah, so the question is what are those slides you have. They have a snap ring holding in a plastic retainer for the slide needle.



Anyone familiar with these?

[3Phase]

Ah, so the question is what are those slides you have. They have a snap ring holding in a plastic retainer for the slide needle.



Anyone familiar with these?

Yep, they're for the '78/'79 carburetors:

1978/'79 Mikuni BS-34II carburetor slide and diaphragm. The jet needle retainer clip and idle mixture screw are circled in Green.


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[puskrat]

so its okay there are no screws there? should i be celebrating? cause i sorta am

[bikerphil]

The 78-79 carbs don't use screws like the 80-81 type pictured in Wildkat's thread.

[3Phase]

so its okay there are no screws there? should i be celebrating? cause i sorta am

Someone put the early 1978/'79 style carburetors on your 1980 bike. Don't mess up the clip position on the jet needle.

Do your carburetors have the idle mixture screw like I showed in the picture instead of recessed in the tower like the ones in 'Kat's picture?

It may not matter because you can easily change them but do your carbs have brass floats or plastic floats?

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[puskrat]

ah, so the question is what are those slides you have. They have a snap ring holding in a plastic retainer for the slide needle.



anyone familiar with these?

that reads like a lob. No, more like tee ball

[puskrat]

Someone put the early 1978/'79 style carburetors on your 1980 bike. Don't mess up the clip position on the jet needle.

Do your carburetors have the idle mixture screw like I showed in the picture instead of recessed in the tower like the ones in 'Kat's picture?

It may not matter because you can easily change them but do your carbs have brass floats or plastic floats?

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Yeah, I have 79 carbs. Guess I missed the clip vs. screws difference on the old carbz. thanks again peoples.

[3Phase]

At least you're not still bored, are you?

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[motoman]

Thanks Phil. Which immediately brings me to my next question. The Tech Tips chart shows main jet size is 137.5. When ordering I find only whole numbered jets, no fractional sizes. should I get a 136 and drill it out? If so, is there a thread where I can get familiar with the practice before I start destroying things? Am I doing this all wrong, and should I wait until I have everything out to try to understand jet selection?

Every 2.5 numbers equals one step, and is the way ALL Mikuni main jets are numbered.
Also, use Genuine Mikuni ONLY!........no aftermarket junk(K&L, RD, etc.).