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Old 04-30-2014, 04:12 AM
Aries42 Aries42 is offline
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Join Date: Apr 2014
Location: delahey
Posts: 2
Default HELP! My NEW bike wont start

Had this bike built by a guy a fair while away from me, and less than two weeks later it's just stopped working.
Managed to run half a tank of petrol, refilled and now the motor won't kick back in at all. The guy refuses to help me or take responsibility.
I'm not great at things mechanically, so i'm at a bit of a loss.
What can it be?

Last edited by Aries42; 04-30-2014 at 04:15 AM.
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Old 04-30-2014, 04:13 AM
Aries42 Aries42 is offline
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Join Date: Apr 2014
Location: delahey
Posts: 2
Default Re: HELP! My NEW bike wont start

It's a two stroke engine by the way, but that''s all the info I know about it.
Can't find a model number
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Old 04-30-2014, 05:33 AM
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mapbike mapbike is offline
Motorized Bicycle Elite Member
Join Date: Mar 2010
Location: Central Texas
Posts: 5,379
Default Re: HELP! My NEW bike wont start

Need more specifics.... and since you know nothing about this or any engine im assuming... this might be difficult. .... but we need more specifics as to how it acted the last time it ran.

I dont always ride WOT, but when I do..I do my best to keep the rubber side down..Ride safely my friends!
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Old 04-30-2014, 08:28 AM
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bluegoatwoods bluegoatwoods is offline
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Join Date: Jul 2012
Location: Central Illinois
Posts: 1,576
Default Re: HELP! My NEW bike wont start

Why don't you start by verifying spark. Trace the wires from the magneto to the CDI to the spark plug. Make sure that these wires have not come loose and are connected properly.

If that all checks out, then remove the spark plug and hook it back up to the spark plug wire. Lay the spark plug threads against the engine and spin the back wheel.
You should be able to see the spark at the tip of the plug.

If this checks out, or if it doesn't, come on back here with that info and there'll be someone around who can steer you from there.
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Old 04-30-2014, 09:58 AM
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Henshooter Henshooter is offline
Motorized Bicycle Elite Member
Join Date: Feb 2014
Location: Melbourne au
Posts: 278
Default Re: HELP! My NEW bike wont start

It could also be something as simple as the choke lever is on , the diagnostics these great members have given me is
1 check spark
2 check fuel
3 check drive train

Check spark by following the steps above , if you have spark that's good and you can move onto the next step , if you have no spark it's either an unplugged wire,a faulty or shorting kill switch or a faulty mag or CDI unit ( yes it's fairly common for new units to give up the ghost or fault after short use )

Check fuel by taking the fuel line off the carby , place a bucket below the line and open the tap , you should have a consistent flow , my estimation is the flow should fill a 250ml cup in roughly 30 seconds if the flow is staggered or a drip drain the tank , check the filter in the tank isn't clogged with crud ( as a member here put it well "chinagirl tanks come with EVERYTHING except fuel" if it is clogged flush with fuel and refit to the tank

Next check the carby , you will need to remove it from the motor to do the next step,>>> there's a small bowl on the bottom of the carby , remove it and check for crud or dirt inside , there should be a small white float in the bowl and a brass tang (u shaped ) on the bottom side of the carby , check the pins holding the tang are in place and the valve moves freely if so move onto the next step.

Check the jet for clogs and crud ,the jet is the small brass top on the tube that fits inside the float ,remove it from the carby and check it isn't clogged by flushing it with fuel and giving it a small blow , fill the tube with fuel and if it flows it's not clogged ( usually you can see if it's clogged by pointing it a a light and looking through the tube ,you should see a small point of light through it )

If all this looks ok then replace the parts you took off and refit the carby to the inlet .

I won't include the drivetrain step as from your comment it sounds like the drive is turning

This is a lesson that we can all in honesty learn , that is buying from an unknown seller or one not willing to back up their product or even help troubleshoot issues with one of their builds within a reasonable limit of purchase should in all rights not be considered as good practice and therefore not used to purchase a kit
I've heard to many backyard sellers either rip off the buyer with inferior or faulty kits and leave them to deal with the issues

I really hope you sort the issue out mate ,maybe post some pics as well to help us identify the motor and carby and possibly diagnose the problem

Regards Henshooter
Light travels faster than sound ,ergo some may appear smart until you hear them speak
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Old 04-30-2014, 10:25 AM
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GearNut GearNut is offline
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Join Date: Aug 2009
Location: San Diego, Kaliforgnia
Posts: 5,106
Default Re: HELP! My NEW bike wont start

So far you have received excellent suggestions.
Also, if you could post pictures of the engine and carburetor it would be helpful.
Note: you need at least 5 posts before the site will allow you post pictures.
Another idea: if you do not have picture taking ability, you can browse this forum and link to pictures that others have shared that match exactly what you have.
"It's a chinagirl. It's a sometimes fun little engine that often will break your heart. It's disposable.

Does not come with a fortune cookie."
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electric, mechanical, troubleshoot

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