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Discussion Starter #1
S&S V124
Super G runs great after dialing in. Been a lot of fun. Bike is torn apart for some upgrades wondering if it would be worth addressing in the carb. I know the mods are the bombsight venturi, boring throat, Thunder jet, and Milling the butterfly shaft. My question is for this particular 124" with 640 cams. Would I gain much from one or more of them?
 

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S&S V124
Super G runs great after dialing in. Been a lot of fun. Bike is torn apart for some upgrades wondering if it would be worth addressing in the carb. I know the mods are the bombsight venturi, boring throat, Thunder jet, and Milling the butterfly shaft. My question is for this particular 124" with 640 cams. Would I gain much from one or more of them?
I have one for sale set up for 124 bomb siight andthunder jet

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S&S V124
Super G runs great after dialing in. Been a lot of fun. Bike is torn apart for some upgrades wondering if it would be worth addressing in the carb. I know the mods are the bombsight venturi, boring throat, Thunder jet, and Milling the butterfly shaft. My question is for this particular 124" with 640 cams. Would I gain much from one or more of them?
Re the bombsight - I haven't tested side by side, but I question its value. Zippers doesn't use them on the G2 or at all as far as I know, and other folks who mod S&S carbs don't either. My G is bored, T-jetted and tricked out - but no bombsight and runs strong. Seems the bombsight would impede airflow.

Interested in anyone's experience.
 

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Discussion Starter #5
Re the bombsight - I haven't tested side by side, but I question its value. Zippers doesn't use them on the G2 or at all as far as I know, and other folks who mod S&S carbs don't either. My G is bored, T-jetted and tricked out - but no bombsight and runs strong. Seems the bombsight would impede airflow.

Interested in anyone's experience.
That's what seems to go along with my search... It seems they bore the throat to improve flow and then impede it with the bombsight I guess the flow stays about the same with it. The T jet seems to make sense and narrow the rpm band each jet is responsible for. The bombsight does seem to improve mid and low end. So was wondering if any of you had run these mods and get hearing info for my next move on this thing. Also looking into possible Mikuni 48 info. Don't want to waste money on a change that wouldn't be for the best. Top end is where my preferred power peak would be but if I could improve both that would be great. And how much change would it really make. It runs strong now but trying to go a tad extra if beneficial. Thanks guys for your time and input. I may be interested in your carb you have for sale just digging for info at this time.
 

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That's what seems to go along with my search... It seems they bore the throat to improve flow and then impede it with the bombsight I guess the flow stays about the same with it. The T jet seems to make sense and narrow the rpm band each jet is responsible for. The bombsight does seem to improve mid and low end. So was wondering if any of you had run these mods and get hearing info for my next move on this thing. Also looking into possible Mikuni 48 info. Don't want to waste money on a change that wouldn't be for the best. Top end is where my preferred power peak would be but if I could improve both that would be great. And how much change would it really make. It runs strong now but trying to go a tad extra if beneficial. Thanks guys for your time and input. I may be interested in your carb you have for sale just digging for info at this time.
In my application, low-to-mid is not lacking and to give up top end for what I don't need isn't a good fit for me.
 

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Discussion Starter #7
I have one for sale set up for 124 bomb siight andthunder jet

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Can you send me some more info on that carb you have for sale? Pics, age, price. Also who did the work. If you've run it and what your impression was before and after on what motor. Thanks
 

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Re the bombsight - I haven't tested side by side, but I question its value. Zippers doesn't use them on the G2 or at all as far as I know, and other folks who mod S&S carbs don't either. My G is bored, T-jetted and tricked out - but no bombsight and runs strong. Seems the bombsight would impede airflow.

Interested in anyone's experience.
which is why they usually want you to shave the butterfly shaft....to regain what you lose with the bombsite....I don't believe any of those minuscule "improvements" are realized on the street....especially with a bigger motor.....the only thing they do is improve the profit margin for the company doing them IMO.
 

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Can you send me some more info on that carb you have for sale? Pics, age, price. Also who did the work. If you've run it and what your impression was before and after on what motor. Thanks
Has the xxx treatment has been run for about 2 miles since rebuild it's a bit much for my 113


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Discussion Starter #10
Would you be interested in an unmodified G plus some cash? Mine runs excellent but untouched other then jets swapped and tuned about a year and a half old still on bike. If not price you were thinking..also I already have air cleaner wouldn't even need that
 

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Would you be interested in an unmodified G plus some cash? Mine runs excellent but untouched other then jets swapped and tuned about a year and a half old still on bike. If not price you were thinking..also I already have air cleaner wouldn't even need that
Text me what you where thinking some reason my messages are full and I can't erase??.... 2095563429

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Discussion Starter #12
Another reason I love this forum. I'm getting the exact carb I wanted for a great price and somebody's getting my carb he can make good use of. Thanks Brad75raiders for a great price. And thanks guys for your input as well.
 

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Does the T-jet really narrow the band the other jets are responsible for. From what I've read at their website in the past the T-jet doesn't do much of anything at all until at least 4500 rpm. Did I read that wrong? I don't spend much time at all in that RPM range. Has anyone here ever installed one and felt any honest increase in their midrange.
 

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Does the T-jet really narrow the band the other jets are responsible for. From what I've read at their website in the past the T-jet doesn't do much of anything at all until at least 4500 rpm. Did I read that wrong? I don't spend much time at all in that RPM range. Has anyone here ever installed one and felt any honest increase in their midrange.
You can use smaller main jets and larger t jet so the power is there when you need it and the MPG are there when you are cruising..

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which is why they usually want you to shave the butterfly shaft....to regain what you lose with the bombsite....I don't believe any of those minuscule "improvements" are realized on the street....especially with a bigger motor.....the only thing they do is improve the profit margin for the company doing them IMO.
Yep - sounds about right.
 

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brad75raiders, is that from your own personal experience?
Yes on my 127ci the super g was about 30mpg on a good day. And 118/125 on the Dyno @ 10.2 compression.
After bomb site (smoothed to butter transition) and thunder jet I went to 40mpg and went 124/138 on Dyno.

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Yes on my 127ci the super g was about 30mpg on a good day. And 118/125 on the Dyno @ 10.2 compression.
After bomb site (smoothed to butter transition) and thunder jet I went to 40mpg and went 124/138 on Dyno.

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I was able to drop my main down 2 or 3 sizes. Believe I was 80/81 ended up 78. That bike is somewhere down under. Shipped it to Australia.!!


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I wouldn't mind getting better mpg. My 120 gets 32mpg regardless of where or how I ride. I once saw 34mpg but that was an anomaly. Not too concerned about picking up extra performance. I don't mind more oomph but not too concerned about it.
 
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