the carburetor tub

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The carburetor tub A plethora of Keihin carburetors. Just like I had two electrical tubs that ended up as an ignition tub and a battery/starter tub, I had two tubs of "carburetor-like materials." It turned out best to make one tub strictly carburetor parts and other for air filters, petcocks, and gas caps. This one is the carb tub. I am going to try the CV Keihins on a couple of bikes and then either convert to them or stick with the old butterfly carbs, I will let you know what happens. You can see what a hodgepodge the tub was as it got moved from California to Florida. file:///C:/Archive/Stage/Open-Sport_stage/Gara... Open-Sport.org The carburetor tub - Sportster garage 1 of 8 7/12/2015 7:12 PM 1 of 8

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The carburetor tub

A plethora of Keihin carburetors.

Just like I had twoelectrical tubs thatended up as an ignitiontub and a battery/startertub, I had two tubs of"carburetor-likematerials."

It turned out best tomake one tub strictlycarburetor parts andother for air filters,petcocks, and gascaps. This one is thecarb tub.

I am going to try the CVKeihins on a couple ofbikes and then eitherconvert to them or stickwith the old butterflycarbs, I will let youknow what happens.

You can see what a hodgepodge the tub was as it gotmoved from California to Florida.

file:///C:/Archive/Stage/Open-Sport_stage/Gara... Open-Sport.org The carburetor tub - Sportster garage

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Here are the contents of the first tub laidout. There must have been a dozenthrottle cables and I already have a bunchof those in the throttle tub, so that is whereI will put these cables.

The second tub had more air filters,petcocks and a bunch of carbs.

This filter backing plate is for my K-Modelrestoration, so I put it on that workbench.

At the bottom of the second tub was abunch of carburetors and a paper air filteryou can cobble into a Sportsteraftermarket filter housing.

file:///C:/Archive/Stage/Open-Sport_stage/Gara... Open-Sport.org The carburetor tub - Sportster garage

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Since this is going to be the carb tub, Istarted with a nice layer of early modelbutterfly Keihins, six of them to be precise.For a simple carb the Keihin works betterthan a Bendix or S&S. It has anintermediate jet that helps you dial thebike in for good driveability all around. Theonly problem with this carb is that theblack plastic fuel inlet elbow always cracksand leaks, and I mean always.

To the early model Keihins, I add twoconstant-velocity Keihins like used on latemodels. It is the only carb better than thebutterfly Keihin. Downside is that it is waybigger and with a rubber manifold youhave to support the air filter with a bracket.

A bag of manifolds, including some steelones. I guess they are "correct" for certainyears, but I think the aluminum ones workfine as well. Pro tip is to always mount themanifold separate from the carb so youcan feel inside as you tighten the clamps.Also if remounting the heads or top end,you actually tighten the manifold clampsbefore tightening the cylinder base nuts orthe head bolts. This way the angle of theintakes on the heads lines up to themanifold before you nail everything down.

And a big bag of manifold clamps. ForO-ring manifolds, you need the stainlesssteel S&S clamps like on the top right.With those, you don't need to support thecarb with a bracket. With a rubber-bandstyle manifold you always need to bracketup the carburetor.

file:///C:/Archive/Stage/Open-Sport_stage/Gara... Open-Sport.org The carburetor tub - Sportster garage

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A bag of butterfly Keihin parts.

A bag of brass elbows you use to replacethe black plastic leak-o-matic ones on theKeihin carb. Be sure to get 5/16 like thefuel line and don't get barbed fittings. Thebarbs will scrape off pieces of the hoseand the chunks are certain to get into thecarb. Same advice for oil lines, no barbedfittings. And that tip comes direct fromracer Vance Breese.

Another bag of Keihin butterfly carb partsand a rebuild kit. You need the Vitonrebuild kit with this crappy gas we havetoday.

This batch of petcocks will go into theother tub, but this baby is for the K-Modelas evidenced by the threaded fitting for thefuel line..

file:///C:/Archive/Stage/Open-Sport_stage/Gara... Open-Sport.org The carburetor tub - Sportster garage

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On top of the carburetors goes the bags ofmanifolds and clamps.

This back is a bunch of metric screws forthe Keihin butterfly carb that I got from Mr.Metric in San Jose.

Another bag of Keihin butterfly carb parts.

And more Keihin butterfly parts.

I tossed all the Keihin parts into the tub.

The carbs faced outward, so I can see.

file:///C:/Archive/Stage/Open-Sport_stage/Gara... Open-Sport.org The carburetor tub - Sportster garage

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[Update:] I did these posts to remind mewhat I own after I unpacked from the moveto Florida. Turns out having the pictures ofwhat is in the tubs has been a great helpfiguring out where the heck things are andwhat I still have versus what I have soldon eBay.

There have been several times when Ineeded some part, and rather than go digthrough the box, I could just look at thesepictures. I am lucky to have them on awebsite where I can see them anywhere,but you could take picture like this andkeep them on your hard drive to remindyou of what you have. Also, if a Hurricanehits, I will be ready for the insurance, sinceI have pictures of all this stuff.

The latest use I had was looking for a carbneedle for my 1979, that has been actingup. I thought it was ignition, but now itlooks like a sticking float needle. I foundsome pictures here, but I knew I had somenew rebuild kits somewhere. Turns outthere were in some gasket drawers I madeup. I will post that soon, but it was just sonice to know where everything is withoutdigging through boxes.

Since it was so nice to know I had somefloats in this carb box, I took the time toorganize the baggies I had tossed inbefore, that you see above. Now I havesome set up like as follows.

Here are some used screws, tocomplement the brand new ones I boughtfrom Mr. Metric. There are some largerscrews in here, maybe for a Bendix orTillotson.

Here is a bag of jets and idle mixtureneedles, and the little rubber plug thatcovers the main jet.

A bag of accelerator pump parts, and thelittle O-rings that seal off the housing.

file:///C:/Archive/Stage/Open-Sport_stage/Gara... Open-Sport.org The carburetor tub - Sportster garage

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Here are some floats and needles andpivot pins, as well as that little screw thatholds in the pivot pin.

Here are some throttle shafts and chokeshafts and a bunch of stuff stripped offcarbs I had to throw away.

These new gaskets were in this tub, I willput them in the gasket drawer.

Here are some used gaskets, I tossedthese back in this tub. I guess this is the'last resort tub" for carb parts.

Here are a bunch of Keihin float bowlO-rings. These swell and are a pain, so Iwill put this batch in the gasket drawers,even though some are used.

file:///C:/Archive/Stage/Open-Sport_stage/Gara... Open-Sport.org The carburetor tub - Sportster garage

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Some used flange gaskets and the 5/16hose to 1/8NPT elbow you need to replacethe cracked black plastic fuel inlet used onKeihins for 30 years. My 96 cracked too.

Some odd-ball stuff. Some wire hoseretainers, I see a gearcase vent elbow,and some other stuff that does not goanywhere else.

Having this stuff organized helped me getthe carb on my 1979 sorted out. It tryingtwo rebuilt kits, the needle in the Biker'sChoice kit worked bettery than a factorykit. Then I had to try a couple of floats andlots of messing around until the carbwould no overflow or stick shut. What apain.

file:///C:/Archive/Stage/Open-Sport_stage/Gara... Open-Sport.org The carburetor tub - Sportster garage

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