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Old 08-26-2015, 03:01 AM
Springfieldscooter's Avatar
Springfieldscooter Springfieldscooter is offline
Motorized Bicycle Elite Member
Join Date: Aug 2011
Location: Springfield IL.
Posts: 281
Default Re: frustrated mom

Hello frustrated mom ....

Spfld. Illinois here.

I bet the great advise here will get you going again!

Post a few photos, ask questions, visit often, and I bet your son will have air in his face soon!
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Old 08-26-2015, 05:54 PM
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Tony01 Tony01 is offline
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Join Date: Nov 2012
Location: San Jose, CA
Posts: 612
Default Re: frustrated mom

Honestly.. sell the motorized bike and just get a road bicycle.. a 15yr old on a new aluminum framed road bike with high pressure tires will be rolling as fast as most people here (25mph).. A motorized bike will up that to 30-35mph.. you decide if you want your 15yo going that fast.. If there isn't a highly hands-on mechanical-mind type person in the family that is willing to learn about and fix ALL of the problems with these bikes, then you're pretty much entering a world of pain. The engine is just the beginning, wait till you get problems with wheels, bearings, chain, throttle cable, brakes, tires, etc. Not to mention anytime you have a bicycle-related problem, NO shop will work on it because of liability issues, so you'll have to remove the engine kit parts every time for them to work on it.

To ride one of these you have to really want to learn and conquer the very steep learning curve in identifying, correctly diagnosing, and fixing problems. Unless your son is very interested in working on his bike and how stuff works.. I would sell it and either get a road bicycle or a moped.. at least you get a warranty and numerous local mechanics for each.
I don't always listen to Alice in Chains..... but when I do, SO DO THE NEIGHBORS
212cc 2-speed
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Old 08-27-2015, 02:31 PM
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MotoMagz MotoMagz is offline
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Join Date: Aug 2010
Location: Michigan
Posts: 1,197
Default Re: frustrated mom

Don't forget the spandex ! I agree except for the road bike... Kids hate road bikes and would never go from a motorized bike to a road bike.. a moped heck ya!!
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Old 08-27-2015, 03:46 PM
dsebastian dsebastian is offline
Motorized Bicycle Newbie
Join Date: Aug 2015
Location: Scottsburg, In
Posts: 5
Cool Re: frustrated mom

Thanks so much for the replies everyone, I've been showing them to my husband and he is working on it when he has extra time. I'm not sure about my son working on it, I think it would be good for him to know about these things but he doesn't have a clue. Hopefully with my husbands help he can learn along the way.
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Old 08-29-2015, 11:05 PM
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Agreen Agreen is offline
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Join Date: Feb 2013
Location: Goose Creek, SC
Posts: 627
Default Re: frustrated mom


15 years? He's plenty old enough. Crash and burn on a 30 mph bicycle or a 60+ mph dirtbike? I think she made a solid choice.

Anyway, let's learn the basics of troubleshooting:

Fuel, air, compression, spark. If you have those, it should run (or try to run). Get them in the right proportions and it should run well.

Fuel: the carburetor controls that. There's usually an inlet valve that you can use to shut fuel off to it. There's a choke lever for cold starts (up is choke, down is for after it starts). There's a button on the left side for getting the fuel to flow in to the carb. I've never needed to use this. Ever. Carburetors don't just stop working suddenly unless something came off of it. I doubt this is the issue.

Air: there's an air filter. It's behind the "punisher" looking black plastic piece. If there's a plastic bag wrapped around the punisher, then it won't run. Otherwise, you probably have air flowing in. Getting air out is important too. If the exhaust got clogged, it could stop running. Ever heard of people putting potatoes in tail pipes? So the air part is probably not likely.

Compression: So the piston goes down, air and fuel go in. The piston goes up, and it compresses the air/fuel mix. Having compression in the engine is important. As was stated earlier, the compression can be lost (without warning) if the 4 nuts on top of the engine come loose. Tighten those bad boys down. Not too much, and do it evenly. If you crank them down too tight they can snap. You can tell if you have compression by riding the bike with the clutch lever pulled, then release the lever. Does it get hard to pedal? Hear a pop pop pop pop? That's compression!

Spark: This is where my money is. You need it to spark to work. When the piston comes up and squishes the air/fuel mix, the spark plug should fire at (or close to) the top. Then everything explodes and makes power! The piston goes down and the cycle repeats. So there's a magnet spinning on the right side of the engine. As it spins past a coil of wire, a little electrical signal is made (called induction) in the coil. That signal goes to a black box called the CDI. The CDI is where the magic happens. It stores electrical energy and fires a whole bunch all at once when the time is just right. Most times when the bike just suddenly quits, either the coil or the CDI is to blame. You can test spark pretty easily. Take the spark plug out, and put the wire on the spark plug again (so now you have a spark plug dangling by the wire) lay the spark plug's metal end on the engine (metal to metal contact is a must). Pick up the rear tire and pedal with the clutch lever released so the engine spins. See sparks? Good!

So there you go. Troubleshooting basics. Fuel, air, spark, compression. That's it. Now you know enough to fix it every time!
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Old 08-29-2015, 11:19 PM
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Tyler6357 Tyler6357 is offline
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Join Date: Mar 2012
Location: Santa Barbara, CA
Posts: 611
Default Re: frustrated mom

I agree, 15yrs old is old enough...I've been talking to another member on this website who is only 14 yrs old, he's doing great!
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Old 08-30-2015, 12:32 PM
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GoreWound GoreWound is offline
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Join Date: Dec 2014
Location: Canada
Posts: 477
Default Re: frustrated mom

in my opinion schools should buy these Chinese two strokes to teach small engine repair basics with. they are perfect learning tools.

you've done good by getting one of these for your kid. encourage him to be involved with the repair, even letting him loose on this forum is probably a good idea, he stands only to learn research skills, if not engine repair.

not to mention the "learning to learn" aspect of having a hobby like this (relatively affordable, and a well tread path before you with lots of advice waiting)

the look on your kids face when the bikes rough bits start to smooth out will be worth it.
Ask me about Chainmail in southern Ontario!
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