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Discussion Starter #1
I just rebuilt the carbs and adjusted the valves and it will only start when I use starting fluid and won’t stay running and backfired and sputters. It seams like it’s not getting enough fuel but I can’t seam to figure it out does anyone have any idea ?
 

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Master of the Electron
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Welcome to the forum!

We need some history... Why did you rebuild the carbs? What did you use? How did you do it? When did it last run well? Have you made any mods since? Etc., etc.
 

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Discussion Starter #4
I rebuilt them because it wasn’t running the best it was really poppy and sometimes loss of power. When I opened them up they were terrible so I bought a kit and replaced everything. I did not do any extra mods. But I did adjust the valves because I read it might be why its not running right and now I have a lot of compression almost too much for the starter.
 

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Master of the Electron
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Rule # 1 - only change one thing at a time! Since you rebuilt the carbs AND adjusted the valves it will be harder to figure out what has gone wrong...

What brand kit? Did you use the kit's jets and needles? Were the jets marked with the same numbers as those you removed? Did you completely disassemble the carbs and clean the body passages? Do you have the airbox lid intact OR is it holed or missing?

What did you use to determine you were at TDC compression stroke?
 

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Discussion Starter #7
I don’t remember what brand it was it was just on amazon and could get here quick but I’m pretty sure they were the same. Completely disassembled them and I have the lid
 

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Master of the Electron
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Do you still have the original jets? I suggest cleaning and re-using them. eBay Chinese kits often have mis-sized jets.

Else, you have committed some error during re-assembly and you'll need to go over your work comparing carefully to the service manual .
 

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Master of the Electron
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Hope that fixes it - good luck! Let us know how it turns out.
 

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Discussion Starter #11
The main jets and needles were different so I put the old ones back in. It started and ran but was so lean it made the pipes get red hot any ideas ?
 

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Master of the Electron
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Are you testing with lid off?
 

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Discussion Starter #16
The right boot from the carb to the heads was leaking so we sealed it and it helped the idle come down a lot but it is still backfiring bad
 

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Master of the Electron
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Check cam timing... verify intake valves are closing right as the 'I' shows up in the flywheel inspection window.
 
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