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2008 V Star 1100 Custom
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Discussion Starter #1
I installed the SS Customs POD kit, and rejected the carbs with the supplied materials. Put it all back together and backfires / pop when warmed up. I can't get the carbs to sync. The gauges are hooked up, and I can see the carbs out of sync. No matter how much I adjust the 'syncing screw' between the carbs, it doesn't seem to change - the needles on the gauges stay at the same levels. Any thoughts?

2008 v-star 1100 custom
SS Custom POD kit
Cobra slip on exhaust.
 

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6,851 Posts
do you have the damper on the gauges so they are not bouncing?

what vacuum level are they reading?

you might have a vacuum leak totally swamping out the minor adjustments you are trying to make - that would cause the backfiring...
 
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2008 V Star 1100 Custom
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Discussion Starter #3
Thanks. I'll start looking for leaks. I was too busy thinking about air/fuel ratio after I rejected, never thought to look for vacuum leaks.

Can hear backfire @ idle in this link:

94912
carb sync.JPG
 

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you have no vacuum on the left gauge - either the adjustment is way off on one side, or you have a leak....
 
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2005 V-Star 1100 Classic
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Did you synchronize the gauges first? You have to do that each time you use that kind of gauge. They have a screw on the dial face to do that. What you do is tee a vacuum source off to both gauges, so you know exactly the same vacuum is hitting them both, then adjust the needles to match. You can use bike vacuum for that, but I prefer to use a Mity-vac that has its own gauge, and match all 3 needles. If you don't have that hand pump, bike vacuum will work too.

Also note what KCW said about the buffering valves, but make sure you don't have one of the valves pinched closed completely.
 

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2008 vstar 1100 classic canadian edition
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are you on the nipple, the front is dirrectly under where the intake rubber boot is, it comes straight out. cant see it until you are under the bike looking up big rubber end with a clamp.
 

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2008 V Star 1100 Custom
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Discussion Starter #7
FYI:
After speaking to S&S Custom cycles (where I purchased the POD kit), advised to check for exhaust leaks, remove the AIS system and/or tear down the carbs again as there maybe a dirty jet. Once I disconnected the AIS system - no more backfire/popping. Still couldn't get carbs to sync. Broke down and took to Yamaha dealer. Took them an hour, but now fixed! Just some more fine tuning of the PMS screw and it will be A-1.
 
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