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Discussion Starter #1
Ok I have some experience with carbs but every v star I work on kicks my ass that being said this is what I have for a set up

Intake is 100% stock
Exhaust system is vance and Hines
I pulled the carbs and checked and cleaned the jets and inspect the slides and needles Everything is clean and moving freely diaphragms are good both needles have five groves the clip is on the 3rd groove with a thin washer on top and bottom plus the thick plastic spacer below everything else front carb is 122 main 17.5 pilot
Rear carb is 120 main and 17.5 pilot
The bike will not idle without at least some choke and pops like a 380 randomly on the rear cylinder what am I missing? Fuel is clean 93 octane tank and filter are clean as well
I am in sulphur springs tx any local guys feel free to come help or call or text 2145161738
 

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stock intake vance and hinds, mains should be 115, stock pilots 17.5 ok, the needle should be set at stock groove. your not increasing any more air into the motor so you don't need anymore fuel... with the pipes you will get a lean condition at full throttle so upping the mains one size is safe. i'm unsure if the 93 is the actual octane rating or something else. 87 octane is what is best.
 

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Discussion Starter #4
That's part of the problem the needles on this bike were already adjusted when I first started on it and don't know where stock setting is and haven't found a clear answer
 

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Discussion Starter #6
I am a bike mechanic so while there is many good things to know in that link I found nothing relevant to the problem at hand
 

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i think the middle grouve is the factory setting. 93 octane is to much these bikes were designed to run on 87 your getting an incomplete burn.check what the pms screws are set at. go to the performance section and carb jetting everything you need is there
 

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93 octane is premium gas the highest priced fuel at the station
Which means exactly nothing.
It actually makes some engines run worse.

As for the pilot jets, gently bottom out and turn out 2 turns.
On most, the entire useful range won't really make THAT much difference.
 

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Discussion Starter #9
Which means exactly nothing.
It actually makes some engines run worse.

As for the pilot jets, gently bottom out and turn out 2 turns.
On most, the entire useful range won't really make THAT much difference.
The pms are at 2.5 turns out i don't think it would be a good idea to do that with the pilot jets
 

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Discussion Starter #10
I figured it out the bike is running fine at mid to full throttle but will not idle or accelerate in the first quarter of the throttle i removed the air filter and manually restricted air flow to the carbs by blocking a little over half of the air duct and wouldn't you know that the bike idles fine which tells me that I have a lean condition at idle only remedied by going bigger on the pilot jets i figure going up to around 20 or 22 on the pilot jets should be just about right
 

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https://sites.google.com/site/vstar1100kb/home/tuning/carb-jetting scroll down to the chart .it labeled for different intake and exhaust setups.for stock intake and performance pipes it calls for the fuel mixture screws to be setr at 2 turns out. easy rider was dead nuts.i have pods and full performance pipes and i had 22.5 pilots in it for a season and i changed them to 20.0 it was to sluggish around town. when you put your hand over the carb the vacumn is pulling in fuel from where ever it can... most likely your pilot jets are dirty. pull them out they have small holes on the sides that plug up. you can clean them with a wire from a plastic bread wrapper.i'd check the color of the plugs.
 

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Your idle circuit/s may be blocked...even one will make a twin falter at idle. A bit of carb cleaner through with the motor running then left overnight may help.
 

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I have a lean condition at idle only remedied by going bigger on the pilot jets i figure going up to around 20 or 22 on the pilot jets should be just about right
And you call yourself a mechanic ??

If what you say is true and the bike really IS 100% stock in all aspects, then you don't solve a problem by changing to non-stock parts.
A real mechanic doesn't try to "adjust" his way out of something that isn't working right.

FIND the problem and FIX it.
 
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