My moped just drove me insane. (please help)

Thomas Middleditch /

Keep in mind, I'm just learning.

Ok, so, I've got a Maxi with a Polini kit and Proma country exhaust. 15mm Bing carb (86 jet) and performance air filter. Those are the only mods. Sometimes, more often than not, the bike will start up great and run great (sometimes a little slow to accelerate but I'm still tinkering with the air filter and the jet size). But today, and this has happened twice before, I had some very frustrating problems.

Essentially it quit running. Aside from the fact that it came at the worst possible time, I'm totally stumped as to why it quit.

The other two times this happened, after a while, it miraculously started up again. Not sure why. Maybe it was flooded and then it drained, however I could find any gas on the ground.

Today it didn't start again. This is after I had been riding it for a good while. I only had limited tools at the time, but I checked the spark plug. Although I still had spark, it was pretty weak. The color of the end was a brownish rust. Just to be sure, I put in a brand new plug (for some reason I had one in my backpack). Still nothing. It's getting gas. I'd take out the plug and it would be wet. The engine has plenty of compression. So what's going on? Is it just flooded? I waited like half an hour to start it again and still nothing. I tried with the choke down, up, all of that stuff. Nothing. If it's flooded why would it run and then after 20 minutes of it resting it just stop? I could get it so if I timed me releasing the clutch right, it would let out a little put or two but then nothing else. It's like it's almost there but then it doesn't fire up.

Keep in mind I'm in Chicago and it's cold, wet, and snowy.

Earlier this morning it had trouble starting and when I took out the spark plug some vapour that looked like steam came out. Don't know what that means. Maybe it was just steam, hehe.

Maybe it could be electrical? My coil isn't grounded the best it could be, I think. Right now it's on the side of the frame where the plastic cover would normally go. Tonight, and tonight only when I was really givin' 'er, trying to get it going, there were blue sparks dancing all over the coil. Maybe I need to cover it up with electrical tape. But still, with that "problem", the spark plug sparks, and the new plug shoots a perfect bright blue spark.

Please help, if you can, I really need this bike to work and be reliable because I use it every day for like 2-3 hours around the city.

Re: My moped just drove me insane. (please help)

my bike had a weird problem like that too. it would die and then run nicely

and then die and run. i swapped out my coil and boot. it turned out my only problem was the boot. the sparkplug boot is crap. get a rubber or plastic one from NGK

Re: My moped just drove me insane. (please help)

You might wanna make sure where the spark plug wire goes into the coil is tight I had this prob a few times with my Maxi tried everything would not start then I started wiggling the wire and it started.

Re: My moped just drove me insane. (please help)

Thomas Middleditch /

Hmm. Ok. It's over in another part of town right now cause I had to leave it there. I'll try it tomorrow. The boot is a new waterproof one from NKG. I'll try fooling around with the coil and spark plug wire. So, you're thinking it's just a connection problem? Anything else?

Re: My moped just drove me insane. (please help)

Having a kit on these bike causes the bike to run a lot hotter then it usually does and these bike run hot stock especially Puchs.

Hens the reason I move my coils away from the block or cylinder heat to either the stock location back on the frame like a two speed or above the head mounting it to the pinch weld of the tank (very touchy area a lot of thinking should go into this before just drilling holes for the mounting bracket)

The reason I move the coil is because heat will break down the internal wrapping of the coil solder points in the coil actually dissipate and ruin the coil.

In your case I don't believe heat is the problem but I'm preparing you for this when you go to mount the coil in the stock location on the block right behind the cylinder.

What I believe has happened to you is a second problem with coils is not having it properly grounded. this too will cause the coil to work harder and to fail.

All though you can see a spark when your holding the plug to the side of the head in actuality it's not sparking enough to ignite the fuel.

1-You said that the plug is wet with fuel so you know it's getting fuel

2-you said that you had compression (check and make sure it's above 110psi any thing over 125 is good standard)

1 + 2 + proper spark = boom.

Before jumping on a new coil check your points and see if they are burnt if they are then clean them but make sure they aren’t pitted if they then replace them.

If the points are pitted and burnt then you didn't have the timing correct. When the bike is kitted then the timing is usually advanced slightly especially with jetting and over sized carb.

If points are fine then swap out the coil. Best to invest in a high energy coil to aid in ignition timing in witch case you wound be able to mount in stock location nor would you want to.

P.S. those all weather NGK boots are very restrictive and will kill a coil as well.

"Welcome to the world of High performance it will age you quicker then crack and prostitutes ever will."

Your fell addict!


Re: My moped just drove me insane. (please help)

yeah it could be a coil, but i would check your points first, then your chassis wiring. In this climate (i'm up in milwaukee) the mist from the wet roads is saltwater, it coveres everything with a salty film of nastiness on my bike, and yours as well probably. I've noticed this makes your chassis wiring all go to shit in short order, and if you get your engine hot, ride around in mist, then cool it really fast, you will have points problems. Id also look at your fuel system, there could be condensation in the gas tank. Get a bottle of HEET, pour a bit in the tank, this is alcohol, and it will absorb all the water, then burn off. Leave that in the tank a couple hours, then get some starting fluid (ether) and spray that in the intake when you try to start it, if that doesnt get it running, THEN waste a bunch of time looking at your electrical system. Oh yeah, and figure out how to use a digital multimeter to find out if your coil is bad, if you havent already.

Re: My moped just drove me insane. (please help)

Thomas Middleditch /

Blarg...I'll try what I can with my limited knowledge and tools. Apart from Pat or Curt, is there any good source for pedding in Chicago? I only ask that because I know those two guys are busy as hell and every day they get a hundred e-mails from kids asking them to "fix their ped".

Re: My moped just drove me insane. (please help)


Re: My moped just drove me insane. (please help)

Thomas Middleditch /

It's new school. Really my own school, but my school is newly formed.

Re: My moped just drove me insane. (please help)

ಠ_ಠ Jon Folks ಠ_ಠ /

Hey man I've practically got the same setup as you. I live in the Chicagoland area and the last time I tried to start my bike(2 weeks ago) it took forever. The bike was outside in the snow for a little bit, so I don't know if water got in the gas, or maybe I've got weak spark or something you might have from running the Polini kit. You should consider cleaning your points real quick, its pretty fast and easy. If you coil and points are fine, maybe its just the weather thats causing the hard starts...

Re: My moped just drove me insane. (please help)

The steam thing sounds like bad fuel to me...some h20 may have taken residence inyur carb but i ain't much of a

pedmechtech either.

Re: My moped just drove me insane. (please help)

ground or mount the coil better. sounded like the sparks jumping all over the coil you mentioned with it firing on the plug then... made me think it may be arcing at the coil and finding ground. i would start at the coil ground it and mount it like it is suppossed to be then go from there....

Re: My moped just drove me insane. (please help)

Thomas Middleditch /

Thanks for the help, guys.

Well, I was in the neighbourhood where I had to leave my bike again today, but I was on a tight schedule so I couldn't tinker with it for very long.

I'm thinking it's definately something to do with the points or the coil. I'm getting one of those coil brackets that mount on the engine soon so hopefully it'll be grounded better. I can't be that it's not getting enough fuel, I've got a brand new 15mm bing carb on there and everything's squeaky clean. Plus, the plug is wet. It's not flooded, either.

I tried to adjust the points today but the little screw was hella hard to undo. I just need to get it back to my place.

But here's what I don't understand...

Out of the engine, the plug sparks. I put in a new plug, just to make sure, even though the older one is fine. It sparks. Not the best looking spark, it kind of looked purple to me, but it was there. For some reason, it's not sparking properly when it's in the engine. Why? What could change?

Re: My moped just drove me insane. (please help)

How's the plug boot?

Re: My moped just drove me insane. (please help)

Thomas Middleditch /

as I said, it's a new waterproof one.

Re: My moped just drove me insane. (please help)

take the spark plug out connect it back up ground it on the engine. Crank the engine over, check for spark. If you got no spark try a new sparkplug boot. Test again. If it runs that's it. If not then check points contacts. get to work!

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