moped jetting...whats it do?

I have a '73 peugeot 102 with a dellorto 14.12 carb on it. it currently has a 50 jet in it and i have been informed that the sputtering it produces is due to that jet being to small, now I have a place from which I can get bigger jets and was just wonder what mechanically speaking will putting in a bigger jet do? if i put in one thats to large will i end up flooding it? How much chance is there that I would completely FUBAR something if i go to large? Any tips or info would be greatly appreciated.

Re: moped jetting...whats it do?

You cannot fubar something by going too large, other than maybe a $2 spark plug. Going too lean you risk fubaring your whole engine.

The main jet is a screw with a hole in it, which fuel passes through. A larger hole means more gas passing through it (pressures being equal before and after jet change). The carburetor works by sucking in air, which by its motion sucks gas up through the main jet, atomizes it, and the whole mixture flows into the combustion chamber. A larger jet will mean more fuel in the fuel/air ratio, also called running "richer". Smaller jets mean less fuel in the ratio, meaning "leaner" conditions.

If you run too rich there will be more oil and gas in the cylinder than there is air to react with, meaning some will be unburnt and will get on the spark plug and foul it. If your plug is black and wet, its a safe bet youre too rich.

On the other hand, two-stroke engines rely on the relatively cool fuel/oil charge to cool off the piston and cylinder, and if the engine doesnt get enough then it gets too hot and too poorly lubricated, and your engine seizes, destroying your top end, maybe your bottom end, and possibly resulting in a crash. When in doubt, always run rich.

Re: moped jetting...whats it do?

goooooogggggglllleeee!

<http://en.wikipedia.org/wiki/Jet_(nozzle)#Jets>;

not a moped carb, but helpful:

Re: moped jetting...whats it do?

Wow got too love a guy who puts post about how poorly made tomos bikes are when he knows so little that he can't tune a sha carb, or even know how up jetting works.

Re: moped jetting...whats it do?

Glad to know im loved, but you should really not go around telling other guys you love them, especially down in the southern states

Re: moped jetting...whats it do?

PS, never said they were poorly made (get your facts right please)

Re: moped jetting...whats it do?

" if they imported 2-3 different makes of the European mopeds (Italian, French, etc.) tomos would get smoked hard core. They are better built, a few are better looking"

Most people would conclude that you'r trying to say that tomos is of a lesser quality then other bikes, ie poorly made. But I'm sorry your right the fact is you made a lame ass passive-aggressive post and then comped out of it. Also implying that I'm gay isn't going to get mad, are you or do you think I'm like 12 years old. I live in Pennsylvania that's not in the south. I've been to very few parts of Canada, and I would never think to stereotype people from let say Quebec, but guess you seem to think its cool to put out the idea that all people from the south are pissed-off gay hating hicks.

Re: moped jetting...whats it do?

the drifter /

umm they do let other manufacuters into this country besides tomos. check the link, its all about jetting and posted recently

https://www.mopedarmy.com/forums/discuss/read.php?f=1&i=523702&t=523361

what i would like to know is what the numbers mean next to the jet, like you have a stock 55 jet, what the 55 stand for, what units of measurement.

Re: moped jetting...whats it do?

Its not about jets or after market stuff, its about full mopeds. Its not that they don't let them in, If I had the scratch I could have this years peugeot brought in but Im talking about commercial importing.

Re: moped jetting...whats it do?

If you go through all those post you will see I even owned a tomos before and I am actually looking at getting a streetmate "R".

Re: moped jetting...whats it do?

Take your homophobic innuendos elsewhere... they are not welcome in our Moped Army community...

That's not the way we roll!

Re: moped jetting...whats it do?

Correct me if i'm wrong.It's either .055mm or .055"

Re: moped jetting...whats it do?

I have never measured a jet with a set of metric pin gages but ohenry could be correct.

In any case the bigger the number the bigger the hole in the jet is and the more fuel can flow thru it at a standard amount of vacuum.

Re: moped jetting...whats it do?

Not homo-phobic, just reactionary-phobic. "OH NO HE DIDNT!!! He just said that the kind of bike I like might not be 100% perfect...Must OVER REACT and insult him for no real reason!!!!"

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