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Discussion Starter #1
I have an 06 vstar 650 that I've been trying to get running for 3 months now. After numerous carb cleanings and vacuum leak checks and pms screw adjustments and needle shims and float adjustments, I think I've finally messed it up. The last thing I did before it started hanging on decel is replace the two hex screws that cover the end of the needles. One day I decided to remove those two hex head screws in the float bowls just to see if I maybe should've cleaned under those during one of the 10 first carb cleanings. The very instant I turned those screws not even 1/16th of an inch, the heads broke right off. I bought new screws from the dealer and I installed the screws and then put the carbs back on and now I have this issue. It starts and idles and revs no problem but the second I rev it and let go it stays revved for 2-3 seconds and then pops a few times out of the exhaust and then right back to idle. I know for sure there is no vacuum leak so I thought it might be lean so I drilled the main Jets (probably way too big for being all stock) but it still runs fine but nothing changed with the hanging. Throttle cables are perfect and everything returns to idle position with ease. I'm at a loss.
 

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Super Moderator "Loose Nut"
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Discussion Starter #3
That's what I forgot to mention. I synced them. I ended up making the sync tool before I even touched the carbs the first time. I've been syncing the carbs after I pull them off and clean them and after taking the needles out to shim them because the choke cable bracket is in the way of one of the covers to the needle diaphragm and that bracket holds the right side of the carbs together.

I think I pulled the white plastic piece with two screws off and looked behind it to see if I was missing anything after I put the new hex screws in. It was a small diaphragm and spring and it seemed a bit dirty so I wiped it off and sprayed it out with brakleen and reassembled it. I thought maybe I messed that up so I took it off and rechecked and it's all as it should be. Besides the two new screws and looking behind that cover, that's the only things I done before it started acting this way.
 

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Super Moderator "Loose Nut"
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I suggest to double check for vacuum leak. As long as cables are not binding and carb return springs good than running lean is the only thing left.
 

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Discussion Starter #5
I checked for a vacuum leak earlier with map gas and there was no change in idle. I decided to throw the sync tool on the bike one last time and by accident I found my problem. I ran my hand along the tube to grab the tail end and I felt a rough section and found a melted spot where it sat on the exhaust and put a little hole in the tube. I cut that section out and put the tool on the bike and found them to be way out of sync and way too high of an idle setting. Besides running a little poor cause I drilled the main jet way too big, it's back to normal. Les, I feel like I wasted your time and my time too but, I appreciate the help and hope I can return the favor one day. Now I'm off to find the stock 91.5 main Jets.
 

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Super Moderator "Loose Nut"
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Definitely not a waste of time. Someone else will have similar issues, look up this thread and know where to start. I'm glad you have it running better. You can repay the favor by explaining your fix to fellow posters in the future. One thing that's great about this forum is there are people who lend a hand to get others on the road. KCW ( among others) is another member that helps a lot of people, I'm sure he's a little like me and has a mental count of the people we have help. If we didn't like doing it we wouldn't be here. Ride often and safe.
 
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