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Discussion Starter #1
Got myself quite the barn find. $400 for a very pretty V Star XV250 with under 1,000 miles. No title. No keys. Damaged only where someone had hammered out the ignition trying to get is started. Had sat for an unknown number of years. Didn't even try to start it. Pulled the tank and did my best to clean it. Pulled the carburetor, disassembled it, and ran it for 30 minutes in my ultrasonic cleaner. (See the image below as to how it looked going in.). Bought a new ignition and put it all back together. It now starts and idles well, with a few hickups that I'm assuming means an uneven air/fuel flow. The PROBLEM is that it bogs and dies with any amount of throttle. My guess is that means a clogged main jet, but since putting it all back together I have pulled the bowl and diaphragm twice, cleaning with spray carb cleaner, trying to clear whatever the problem is. No effect whatsoever. I did put a new fuel pump on, hoping that would do the trick. Nothing changed. With less than 1,000 miles I've got a hard time believing anything has failed. Capable of no small amount of self-hate and loathing, I've gone over it several times sure that I misrouted a vacuum line or something painfully simple. I cannot find it. Guessing this is a simple fix. Logic insists its the main jet, but it is clean and clear.

Your suggestions, please.
Twinkle 1.jpg
 

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Super Moderator "Loose Nut" - Houston, Texas
2001 Vstar 1100 Classic (sold), 2006 HD Electra Glide Ultra Classic
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Sounds like some of the jet passages are still clogged. All the holes must be 100 percent clean. Check the side holes in pilot jet. Is float set correct and do the floats bounce freely?

105046
 
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Discussion Starter #4
Good call. I have done that, plus put the aerosol carb cleaner straw into the end of the jet and sprayed until I saw fluid coming out of all those little holes. Unless they are somehow instantly refilling/blocking, that's not this particular problem.
 

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Super Moderator "Loose Nut" - Houston, Texas
2001 Vstar 1100 Classic (sold), 2006 HD Electra Glide Ultra Classic
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How about the float jets? Here's a thread talking about them.

 

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If you have boots between the carb outlets and engine intakes, I would suggest you inspect them for cracks or poor seals where they bolt to the engine. Some suggest spraying a little carb cleaner around the seal... if rpms increase, you have a leak. Good luck... spray sparingly... it is flammable after all.
 
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Discussion Starter #7
I did replace the intake boots earlier. Beasts to get in and out.
Carb float ... that is my next piece to replace. Ran the bike over rough ground yesterday. Idle got very choppy. Thinking that means the float is not functioning properly.
I can pick up a chinese carb for this 250 for about $60 on ebay. Hate to do that, but that's almost the same cost of a carb rebuild kit.
 

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Discussion Starter #8
Just watched a great video on adjusting the tang on the float. It completely defined my situation ... as in the float is sitting too low (the tang is bent wrong), not allowing enough fuel in, and the motor is running out of fuel when I twist the throttle quickly. Now I need some numbers ... as in what angle to put the carb at on the bench and what the float height should be at that angle. Quick search found nothing. Will keep looking. Help if you can. Here's the video.
 

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You can find your 250 shop manual in the link attached. The following 2 pgs are from a Virago 250 which was rebranded as a V Star at some point. Hopefully, it is similar....

105158


105159


 

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Discussion Starter #10
That is an interesting system. A 1 millimeter window to hit while removing, disassembling, adjusting, reassembling and reinstalling the carburetor. Makes couples-therapy with my Ex sound almost appealing. But we do what we have to do.
 

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That is an interesting system. A 1 millimeter window to hit while removing, disassembling, adjusting, reassembling and reinstalling the carburetor. Makes couples-therapy with my Ex sound almost appealing. But we do what we have to do.
I would suggest watching the linked video. Although it is for 650 carbs, it shows some good techniques for making the adjustments on the bench. Float adjust starts at about 4:30' in.

 

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Discussion Starter #13
Bad news. It isn't a float issue. Took a shortcut and installed a new float (with a noticeably different tang angle that should have run rich) with the carb on-bike. Wanted to see if that made any difference. Result: Zero difference. I'll pull the carb this weekend and clean it again. I'm also looking for a place to install a fuel filter. There could still be crud in the tank negating any carb cleaning.
 

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refer to the Partzilla website for your year, make and model. They have part diagrams by major systems like that below. Make sure to manually clean the jet passages that Lesblank mentioned above. Remove and clean your fuel lines, drain the fuel tank and inspect for rust, and replace your fuel filter. I would replace the float needle and seat while the carb is apart. If this diagram below happens to be your model, it appears the filter is in the tank bottom outlet (#12 below)
105321
 
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