Carb jet needle question

My engine on Honda Cub 50cc runs too rich , lots of soot on the spark plug .In the manual it says to lower the E clip one notch . My question is do I move it toward the blunt end of the jet needle or the pointed end ? Thanks

Re: Carb jet needle question

You need the needle to.go lower in the jet...move the clip.toward the top or blunt end of the needle

Re: Carb jet needle question

Thanks for the information, that’s the way I moved it but wasn’t sure, it’s still burning rich but I have one notch left maybe I’ll move it . Would a different air/fuel low speed adjustment screw valve make a difference also? It’s a Chinese clone carb but runs good , I was thinking about taking the air /fuel valve from the original carb and swapping it with the Chinese carb. Thanks again

Re: Carb jet needle question

Pushrod Fifty /

Carb is too big for it.

Re: Carb jet needle question

Do you mean the carb is too big for the needle ?

Re: Carb jet needle question

No he's saying the carb itself is too big.

Re: Carb jet needle question

Pushrod Fifty /

Best to fix and use the original.

Re: Carb jet needle question

I’ve been trying to get the original carb to run but haven’t quite got it yet; I’ve cleaned it several times , installed a rebuild kit .cleaned the fuel tank and replaced the fuel lines. The problem is all low speed , idling speed is erratic and sometimes stalls like it’s not getting fuel I’ve cleaned the float.replaced the valve and jet . No vacuum leaks.

I’m working on the peacock assembly now .I just can’t seem to get any consistency.

It’s also running rich , however it’s running almost always on idle

Re: Carb jet needle question

Pushrod Fifty /

There are some real small passages in those carbs but once clean and sealed, they run real well. If you have access to an ultrasonic cleaner, or buy a jewelry ultrasonic cleaner maybe on amazon, or buy the one gallon Gunk carb soak and soak for a week. Follow up with chasing passages with speaker wire strands, carb spray and compressed air. Mounting flange- check flatness, use small thick flatwashers not lockwashers. Use original jets and not ones that come with carb kits.

Also make sure the mounting spacer is flat, new o-ring, base gasket, Hondabonded.

Any little airleak in the setup makes them sputter and not return to idle fast enough for a smooth shift. I have gone through every leakpoint by replacing the little o-rings in the carb.

Re: Carb jet needle question

Thanks for the tips. Will the bike basically idleing for a long period of time carbon /soot up even if set up right? Compression is 85 on my Harbor Freight tester . The manual says 90-95 is spec . The main jet that came with the kit is #80, the original on it is #88 ,the air /fuel jet is 38 with the kit and original is #35, should I use the original idle screw also . Where can I get an o ring for the base of carb.ill piddle around wit it today. The cub came out beautiful and everything seems to function well,just the nagging idle problem. Thanks again

Re: Carb jet needle question

Pushrod Fifty /

Its s non-standard o-ring size. If you get one from Honda, try ebay ir dratv.com. Making 2 gaskets for each side is the other option.

Re: Carb jet needle question

I have another problem with the carb today after cleaning it again. It’s leaking non-stop from the bottom overflow tube I spent hours trying to fix it . My first and obvious thought was the float sticking, but that’s not the problem I took it down the basement and rigged up a fuel system using water.Im using the same parts as before and had no problem with leaks .i placed around with the peacock unit thinking maybe screwed it up . Nothing worked Do you have any idea what would cause this other than the float? Thanks

Re: Carb jet needle question

Water is thicker than gasoline .

Pull the carb and polish the float seat bright shiny . Inspect the needle tip for any deformities . Check float level .

Re: Carb jet needle question

Pushrod Fifty /

I lapped my needle to the needle seat with fine Clover compound, never leaked since.

Re: Carb jet needle question

I might have found the problem after hours and hours of piddling around . When I went through training for running machines at Timken Bearing our instructor told us the most beneficial tip . He said if your machines are running along fine and all of a sudden things go South, ask yourself the question What did I just do ? In this case I new it was something I did but couldn’t think what it was . The filter cup was rusty so I soaked it overnight in evaporators. I just happened to pick it up for the umteeth time

,looked at it under a magnified light and it had around a dozen small holes ,the evaporust ate the rust off that was covering the holes, that’s what hopefully is causing the problem. I coated the holes with J-B Weld and will give it a go tomorrow. In the meantime I ordered a used carb that came off a 65 Cub , same as mine . Thanks for all the feedback.

Re: Carb jet needle question

Doubtful that JB will hold for very long .

Re: Carb jet needle question

The carb from EBay should get here soon ,maybe that part will be good. I just tested it for leaks and it works so those pin holes were the problem. Thanks

Re: Carb jet needle question

Pushrod Fifty /

Good find!

Re: Carb jet needle question

The carb looks to be in good shape I’ll have $50 worth of fun just tinkering around with it , add it to the pile of fishing reels and other stuff laying around collecting dust. It’s amazing how much you can learn about problem solving just tinkering around . One question on this carb . There’s a piece on the Petcock assembly called the cock packing , does this have to be in a certain place ? Mine has 7 holes and a solid area in which a hole is skipped . I don’t want to screw this up too. Thanks again

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