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Discussion Starter #1
Ok I got the bobber back together (2003 Vstar 1100 with 1.75" straight pipes) and installed the SS custom cycles POD kit and new plugs. I talked to them on the phone and went over the bike for the jets I should run. I installed the jet kit, - d shimmed the needles with 1 shim and drilled the PMS screws. Put it all back together and it was popping through the rear cylinder exhaust side at idle and less than 1/4 throttle. I tried going Rich on the PMS and nothing changed, tried going lean and nothing changed. So I removed the 1 shim and now it idles perfect but now I wAs getting popping and small flame from rear cylinder at low throttle with popping through the cArb so I went little more rich on the screw and now I'm just getting loud popping at 1/4 throttle or less. I can rev it to the limiter and it will pop a couple times on its way to idle. I'm able to drive it but it just pops at starting speeds and pops randomly during decel. Any advice. Also I pulled plugs at 2 different times once before removing the shim from the needles and another time after test ride and both times they were rich
 

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Sounds almost like ur way rich. Popping and flames would indicate excess unburned fuel igniting in the exhaust. Which would be confirmed with the noticably rich plugs. What size jets did you install?
 

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intake valve on the popping cylinder may be leaking from being too tight, do a leak down test on that cylinder, ether that or there's an air leak at one of exhaust joints or the intake manifold. it doesn't take much of a leak ether on my 650 the cap over the sync port was leaking and it caused really bad popping on the rear cylinder, i don't know if the 1100 has that cap but if it does check for a leak there.
 

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Discussion Starter #4
Sounds almost like ur way rich. Popping and flames would indicate excess unburned fuel igniting in the exhaust. Which would be confirmed with the noticably rich plugs. What size jets did you install?
That's what my origina thought was so I took the rear cylinder screw out a 1/4 then then 1/2 then then started getting popping in the crab as well as the exhaust so To me that's lean but the exhaust side is throwing me off.
They had me do the 152.5 mains and the 20 pilot and 1 shim in the needle which I removed and did get a smoother throttle
 

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Discussion Starter #6
So an update, I ran the bike and pulled the plugs again, 5!3 front showed a little lean so I turned it out 1/2 turn (no more carb popping) and the rear plug looked perfect. Still getting popping at about 1/4 throttle only. I sprayed everywhere and couldn't pick up a leak anywhere but it's to the point I can ride it just have to deal with the popping at 1/4 throttle
 

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Discussion Starter #8

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Discussion Starter #9
Ok so as stated I would check back in after I pulled the carbs and went through all the veins with some cleaner and so on. Well I pull them out and start breaking them down. As I flip it over to pull the bowl off I hear something rattle around. At first just thought it was maybe a carb wiring clip hitting the housing, well I was wrong. I pull the bowl cover off and the Main jet is unscrewed and laying in the bowl. Luckily nothing is damaged I checked over everything and continued to clean both carbs as I intended. Put it all back together and both carbs start shooting fuel from the overflow even as it is turning over, Guessing the floats are stuck from where I drained the bowls (by running it with fuel off) prior to pulling them off. Tomorrow going to mess with tapping the bowls to try and free them up and avoid pulling them again. Got a few tips from other threads about running it dry then with fuel, and repeat a couple times and taping on the float caps as they are empty. But will see if the popping issue is resolved once I fix this crap.
 

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Discussion Starter #11
so yesterday my son got really sick so had limited time working on the bike to give the wife a break of dealing with a sick 6 year old but i was able to pull the carbs off and the bowls, did see anything wrong but still cleaned them and then just hooked up the gas lines and turned the key on 4 times and looks like that fixed the carbs leaking. today i will put them back in completely and take for a drive. will post back when its done and tuned.
 
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