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Rebuilt carb, still no response?

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Finishing up my winter project. Its a 1975 CB125 cafe'd. Rebuilt the carb, and I am still getting little to no response with my air/fuel adjustments. I cant get it to idle, and at bogs out at full throttle.

I was going to move the needle up or down a clip, thought I would get some opinions first. Also was thinking bigger main?

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I moved the clips on the carb needle, still nothing. I also found out when the choke is on, the bike turns off. Anyone got expert advise?

Sounds like too much fuel in both cases. Try dropping the MJ 1 size and see what happens at WOT. Have you double-checked the float level?

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what did you replace when you "rebuilt the carb"?

assuming you've checked all the basics then there might be a different root cause than the carb...

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Got it to idle, but...

Fast throttle twist, bogs out only when reving in neutral

Riding on road it takes awhile for throttle to respond

Im thinking its too lean, but my spark plug is a perfect tanish grey...

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Bogging in neutral is okay. Only tune-out a bog that happens while riding the bike.

What did you do to get the bike to idle?

If the bike is unresponsive, try 1 size richer main jet and/or lift the needle 1 or 2 slots.

If richer is worse, then go the other way.

Modern fuels are hard to diagnose by plug color. It's common to have a tan insulator and black shell and still not have the mixture quite right. Keep posting as you tune it. :thumbsup:

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I moved the needle up(clip down) to make it richer, it runs better through the gears, and has better response.

I got it to idle by turning both idle and air screws in all the way, and backing them out to factory settings.

It also idles way better and starts a bit better too, It still barley idles when at stop signs, and some times shuts off because it idles so low, but I can live with that, its 10X better than what it was like.

I feel 100% confident when rebuilding carbs now!

Thanks David for the great advise...

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