MOPED ARMY

Matt, Just because you go faster without the airbox, doesn't mean you are running rich...A lean moped will go very fast, until you seize your engine. Have you done a plug chop? What color is it. If it isn't really black, then you aren't running rich. First things first... do a plug chop...Get a new plug in there, and get your ped warmed up. Then ride it about a quarter mile at full throttle. Once you are at top speed for a little while, hit the kill switch with your thumb. It is important that you hit the kill switch while your bike is at full throttle. Park it, then take out the plug and check the color of the ceramic part underneath the contact. You can let it cool off if you want to, but I never do. Once you do a chop; If the color is really dark, first you should check to see if your airfilter, inside the box is really dirty. You can tell because it will look black on the side that faces the hole in the airbox. This happens a lot. At any rate, take it out and clean it with brake cleaner, and then see if the ped runs any faster. You may have to cut along the edge of your airbox with a razor to get it to pop open, because they are usually sealed...but don't worry, because they are hinged at the bottom and close right back up, even after you have broken the rubber seal....they were meant to be opened. Do a plug chop after that and post back. I bet this is your problem. If you still aren't satisfyed, that is when you start modifying the airbox and buying bigger jets.

Chris

Ok I went to my moped guy, Larry's house ..he's an old retired car mechanic that tunes up peds for fun. A really great guy and quite a character.

Before I went over I took my carb apart. The jet in my carb was a 60. We poked through a pile of stuff and found a 58. When I got home I put it in. The bike runs great and plug chops are tan. Top speed is ~34. And Chris I had taken the airbox apart and cleaned it and the metal mesh filter.

The main point that I was trying to get at is:

Will a moped theorhetically go faster with a larger jet and no airbox, than a ped with an airbox and a propererly jetted carb? In the first case the engine is getting the maximum amound of air and fuel, and in the second case it is getting the same ratio but less mixture. Is it the ratio that counts or the ratio and the amount?

Also when I swapped my jet from a 60 to a 58, I noticed something wierd. The jet in my carb was very small, about the size of a pencil tip. It threaded out with a screw. The jet I got at moped guys house was really big, and long. I had to remove the lower piece of the jet with a ground down socket wrench.

Whats the difference between a two and one piece bing carb jets?

Also does anyone think that enlarging the air port of the carb would allow me to put in a larger main jet or would this be a waste of time.

Thanks for reading all this. I tried to make sense but if you've got some questions let me know.

Matt

Matt,

All else being equal, the more mixture you burn per unit of time, the more power you generate.

I like to pick the correct jet without the air box and filter, by doing plug chops, then do whatever I have to to the air box and filter, to allow the ped to breathe easily. Others have posted about air box mods to various brands of peds.

Ron

I already took the hose off, and I've taken apart and cleaned the airbox and steel mesh filter.

I'm pretty happy with the way its going now...34mph and good accelleration

I may try the size 60 jet and the performance airfilter that I use on my Zuma scooter and see if I get an improvement.

The only bad thing about this ped is it vibrates so much when its going 34mph my butt practically goes numb... I have to stand every now and then.

Has anyone tried enlarging the air intake port?

Thanks

Matt