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Carb options for a UL

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Old Jan 17, 2023 | 06:08 PM
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Default Carb options for a UL

Good afternoon. I’ve been pondering what I want to use carb wise when I get my UL together. I do not have a linkert. I’ve seen folks talking about using mikunis (38 or 40mm?). But I have a super B laying here and could machine an adapter. Would this be too much? They cover a wide range of displacement from 55” up to 100” depending on jetting. I also have a super E. Just curious on all your opinions since I have very little experience with these engines. I’m in no way against a mikuni but I was just curious about the options for the s&s’s. Thanks!
 
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Old Jan 17, 2023 | 07:49 PM
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The stock U carb has a 1-1/4" butterfly with a 1-1/8" venturi with a three bolt carb flange. My gut says the S&S is too big even with smaller jetting, unless you change the venturi (if possible) because a big hole is just that regardless of jetting.
 
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Old Jan 17, 2023 | 08:28 PM
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Originally Posted by hellonewman
The stock U carb has a 1-1/4" butterfly with a 1-1/8" venturi with a three bolt carb flange. My gut says the S&S is too big even with smaller jetting, unless you change the venturi (if possible) because a big hole is just that regardless of jetting.
thats my thought. I could probably make a sleeve to choke down the super B but that’s a lot of R&D. Thank you for the stock measurements. I sized up the super B with the stock manifold and noticed the size difference and how that would affect performance.
 
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Old Jan 17, 2023 | 09:13 PM
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Need to make a correction , the choke plate is 1-1/4" diameter then the body steps down about another 1/8 before the venturi. The throttle plate is 1-3/8".
 
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Old Jan 18, 2023 | 07:09 AM
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Get the correct carb and install Ed’s E2000 ignition and dont look back - it will start 2 or 3 kicks cold once you get the rhythm down usually 1 kick at a hot stop

all the fluff about carbs - is like trying to convince a hot chick a short one feels the same and a long on
 
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Old Jan 18, 2023 | 08:19 AM
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As John so eloquently described, at the end of the day a Linkert will do the job perfectly, no reason to reinvent the wheel on that one. Aftermarket is not going to improve performance, if anything it might hurt being too big.

And a Linkert is cooler than anything else you suggested, just find one and get it mounted. Good luck.
 
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Old Jan 18, 2023 | 09:58 AM
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I'll check at the shop, we may have a Linkert for sale.
 
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Old Jan 18, 2023 | 10:19 AM
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Originally Posted by rizzo
I'll check at the shop, we may have a Linkert for sale.
awesome. Thank you!
 
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Old Jan 18, 2023 | 08:44 PM
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Sorry, it's been claimed for an upcoming knucklehead project.
 
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Old Jan 19, 2023 | 06:21 AM
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An M51 isn't hard to find, I believe WL's had them with the smaller venturi, the UH had a slightly larger venturi which you can buy reproduction and change it. You can also buy a complete reproduction carb as well.
 
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