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I'll attempt to keep this short. I have a 2007 V Star 650 Classic, Cobra slash cut slip on exhaust and stock air.

Due to decel poping, I disabled AIS, which helped w/75% of the issue. After reading many threads about this issue, I got a Dyno Jet Stage 1 jet kit. (Yes I know, I could have just got jets for a lot less. Read those posts after it was too late).

I installed needle jets and main jets as instructions, double checking twice before buttoning up. Set PMS screws to 3 rotations out as per instructions.

Everything seemed to work ok at first, until first test ride. With bike warm and after riding for about 15 minutes, came to stop light and it died waiting for the light to turn green. Strong smell of fuel, as it bike was running too rich. Bike stalled at every stop light/sign on the way home. Got home and hit the forums. After some reading, I started making slight adjustments to PMS screws. Nothing seemed to really work. It either ran too rich or wouldnt keep running at idle.

Took out everything installed for jet kit and put back in stock parts(advised from local shop). Set PMS screws to where it was before (front 1 1/2 and rear 3 1/2 rotations out). Runs better, still difficult time to maintain solid idle. Had to step up idle speed to keep running while sitting in garage. Took it for a ride and noticed that while trying to open it up between 3rd and 4th, it would fall in its face sputtering. If i let off, it cleared up. This was a first.

Im going to replace fuel filter and clean out the pilot jet holes on Monday. I've checked for air leaks, plug fouling and jets installed. I've read a lot of other threads and hope I didnt miss something. My apologies if I did.

Any other suggestions or ideas? Thank you in advance.
 

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Before you go back into the carbs, try a new air filter, perhaps a high flow filter like a K&N. The reason I say that is because if you putting more fuel in, you also need more air in. Gotta match the air with the fuel.

I did the same exact thing to my 650 as you did.


thanks,
Delkster
 

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Discussion Starter #3
Ya that makes sense Tadelk. I've replaced the air filter with a new stock one. Been avoiding doing an aftermarket since they are expensive. My other concern with after market open air kits is rain/water that might get in if I get caught out in a shower.
 

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I'm no tech or motorcycle mechanic, however I'd agree with Tadelk. Without being there myself it would seem its starving for air since the carbs and exhaust have been modified hence the stalling at lights/stop signs. Just my 1.5 cents worth and I certainly hope this helps. Please keep us updated as we all love to learn here.

Sent from Motorcycle.com App
 

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Thanks Keith. I would certainly agree with the lack of air if I still had the jet kit installed. I've since put the stock needles and main jets back in. It no longer stalls at a stop, but now it just wont open up on the road with out it sputtering. As this progresses, I'll keep everyone updated. Nothing worse than posting a problem and never the end result/solution. ha ha
 

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Discussion Starter #7
The original jets are put back in and pms screws were put to where they were originally before trying out the jet kit. Since I knew from before the jet kit that the front cylinder was running lean, I've since set it to 2 rotations out. The back is now at 3 and it seems to run more smoothly. If I failed to put this crucial info in my original post, I sincerely apologize.
 

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Discussion Starter #9
No worries Nick57, I'm a big boy and can handle it. Ya, I read about the adjustment on the pms screws with stock set up a little late. Like after purchase of jet kit that I can't use late. ha ha
 

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the reason for popping on decell is the slipons they amplify the sound.A stock bike pops but you cant hear it thru stock mufflers.These bikes come from the factory set up lean to meet epa rules.Opening the pms screw a little will take care of popping.if you dont increase the amount of air going in you dont change the jets.very important is to sinc the carbs.
 

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Discussion Starter #11
Sorry for the lack of updates, been busy the past few days. So today, I took the carbs off to clean them. I found that the main jet on the rear carb was almost all the way unscrewed. I know it was tight when I put it in, so its strange to me how it could have become loose. The other jet on the front carb was tight and no problems.

I finished cleaning and used an air compressor to blow everything out. As I was reassembling the covers for the needle jet side, I noticed that one of the screws (new hex head ones I replaced crappy copper screws with) was a tad too long as it went thru the body edge. The end of the screw was just barely hitting a shaft on the back side of the housing. I don't know what this shaft does, but it has a spring on it and slides-controlled by vacuum im guessing. I used a washer on that screw to reduce the depth and not hit the shaft behind it.

Put carbs on the bike, added some choke and started it up. Once it warmed up, had to make some small adjustments to air/fuel mixture screws. It idles much better than it had a week ago. Got it out on the road and no problems stuttering when the throttle is wide open now.

I'll take the bike on a longer ride in a few days and then check the plugs to see how my air/fuel mixture is. I think I still need to get it into a shop and have a pro fine tune it and sync the carbs for me.

Any ideas or solutions if that main jet gets loose again? Thanks again for all the input and feedback from everyone.
 

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I used some stuff called "lock tight" on one of my pms screws. I had trouble with the front one loosening up while riding, used a dab of lock tight on it and now no more troubles.
Just a little dab will do you.


thanks,
Delkster
 

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I used some stuff called "lock tight" on one of my pms screws. I had trouble with the front one loosening up while riding, used a dab of lock tight on it and now no more troubles.
Just a little dab will do you.


thanks,
Delkster
Use the BLUE lock tight! If you use RED you will never get them to move again!
 

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Thanks Keith. I would certainly agree with the lack of air if I still had the jet kit installed. I've since put the stock needles and main jets back in. It no longer stalls at a stop, but now it just wont open up on the road with out it sputtering. As this progresses, I'll keep everyone updated. Nothing worse than posting a problem and never the end result/solution. ha ha
I have had great luck with this after changing my jetting and exhaust changes.
Air Box Mod
 
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