signs of over carburation?

🇮🇹💦 Of the Loin /

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Jan 26, 2009 06:55PM

So Im pretty sure its just that i have a huge idle jet (not pilot jet) and thats why my bike is being gay and not wanting to run, but im also curious about what else it could be,

60cc eurocylinder, 19mm phbg, i opened up the intake, and then lowered it by about a mm, but havent touched the exhaust or anything (big ass exhaust).

This shit ripped with a massive exhaust leak, so im pretty sure im just jetted rich, I feel uncomfortable going down in main jet size tho.

45 idle, 60 pilot, 74 main, w7 needle at top setting.

Re: signs of over carburation?

Jesse -B /

jtbechtold

Jan 26, 2009 06:59PM

I would put a smaller idle jet in there.

Re: signs of over carburation?

🇮🇹💦 Of the Loin /

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maitland OP

Jan 26, 2009 07:01PM

thats what im thinking. cuz it ripped once. for like 10 minutes.

not used to working with big carbs on small kits.

Re: signs of over carburation?

Tommy Too Tall /

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thomasw

Jan 26, 2009 07:26PM

Piston ports and 19 phbg's like small Idle jets, my 65 metra has a 35 and is still too rich.

Re: signs of over carburation?

) Cupermcnewbster ( /

boardmonger

Jan 26, 2009 07:28PM

I was running a 55 in my airsal but I had a leak of course.

Downjet your idle.

Re: signs of over carburation?

Jesse -B /

jtbechtold

Jan 26, 2009 07:29PM

I am running a 45 on my 70cc k-star kit. with an 87 main jet. Also if you have that screw on the side not the idle screw but that brass one. Make sure it is not turned in all of the way. My will not start if this happens.

Re: signs of over carburation?

Novakarl /

novakarl

Jan 26, 2009 09:27PM

I'm not sure I have the nomenclature correct here. One of the things in the wiki refers to the jets as main, idle/pilot, and choke/starter.

So the idle jet feeds the idle and progression circuit, and the pilot jet feeds the starting circuit? Is this correct?

I can get my engine to idle decently by adjusting the idle mix screw, but if I crack the throttle to WOT from idle, the engine bogs, but it runs fine once the RPM increases.

Is this the same problem you're experiencing? I'm just a little afraid of leaning out the mix too much at closed throttle, and not getting enough lubrication while decelerating down a hill. I guess if a smaller idle jet doesn't help I'll put the 50 back in, and try something else.

Let me know if you get it solved :D

Re: signs of over carburation?

Todd /

tizzle

Jan 26, 2009 09:54PM

Does anybody know what that little brass screw does that jt was talking about?

Re: signs of over carburation?

naz /

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michaeln

Jan 26, 2009 10:10PM

Kart Piston ports like the KT100 often like to run a little leaner as well in the lower range so they can get spun up and then can be richened up after that. I think metra65 seem to kinda respond in similar manner.

-naz

Re: signs of over carburation?

bfa /

Jan 26, 2009 10:49PM

I know a sign of overcarburation. It's the fact that you still have that carb you borrowed from me in September!

Re: signs of over carburation?

Novakarl /

novakarl

Jan 27, 2009 05:14AM

It's all relative. Sounds like overcarburation for him and undercarburation for you :P

Re: signs of over carburation?

Eric Sabatino /

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erics

Jan 27, 2009 05:20AM

Most people here seem to be running between 35-45 for idle jets.

With the cold, the peugeots are getting up into the 110's for mains!

Re: signs of over carburation?

🇮🇹💦 Of the Loin /

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maitland OP

Jan 27, 2009 05:39AM

i run a 55 in my gila which is why i always think idle jets are high

Re: signs of over carburation?

Eric P /

neutral4x4

Jan 27, 2009 09:52AM

OK

The starter jet controls the choke and almost never needs to be changed from what came with the carb.

The idle/pilot jet controls the throttle from stop to 1/8th throttle. The little brass screw on the side of the carb fine tunes this jet. Turn the screw in to lean the mix and turn it out to richen the mix.

The needle controls the mix from 1/8 throttle to 3/4 throttle.

Finally the main jet controls the mix from 3/4 throttle to WOT.

Just tune for what works. Other people's bikes are only a base for tuning. You have to tune for what your bike likes, not other people's bikes.

Re: signs of over carburation?

🇮🇹💦 Of the Loin /

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maitland OP

Jan 27, 2009 04:28PM

yeah well jettings been a huge bitch around here sabatino

cuz it was like 80 degrees a week and a half ago, and then it was humid and raining, and now its a dry january. prob be hot again soon i dont even know whats going on this year,

Re: signs of over carburation?

David Ciao /

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davidw

Jan 27, 2009 04:57PM

Piston ports and 19 phbg’s like small Idle jets, my 65 metra has a 35 and is still too rich.

my 21 phgb and 65 metra is the same. 35 and still seems high

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