just bought new motorized bike. need help already.

GoldenMotor.com

2tontarantula

New Member
Dec 4, 2012
9
0
0
Las Vegas NV
I just purchased a newly built motorized bicycle. It ran for about 10 minutes then died and will not start. I checked the fuel components and they were ok. when I checked the spark plug and spark plug cable I realized the cable had come loose from the CDI. So when I went to re tighten the cable on the boot side I noticed that the screw in the boot had come loose, and when I pulled on the cable the whole screw came out of the boot and was partially screwed into the cable. I purchased a new spark plug and boot. installed both and tried to start the bike but it would not turn over. When I checked for a spark there was none. I'm guessing it may be the CDI but have no experience with one. any suggestions?
 

Groove

New Member
Nov 2, 2012
245
2
0
Lexington, KY
Make sure the boot is firmly snapped into the plug. The automotive grade plugs have a 'tit' and require an automotive grade boot. By looking inside you will see the difference as compared go the stock plug and boot. It is my understanding that they're not interchangeable.
 

2door

Moderator
Staff member
Sep 15, 2008
16,302
175
63
Littleton, Colorado
As has been said here many many times; the kit supplied spark plug boot should be the first thing you replace. They are a constant source of trouble. You need a good automotive quality boot, one that uses the top cap that comes on all spark plugs. The kit boot requires that the top be unscrewed and removed leaving only a small threaded portion for electrical contact. That's just wrong!

The plug wire in most new kits is glued into the CDI terminal. It can be removed and replaced with a new wire but it's best to look for a solid, metallic core wire as opposed to the resistance wire sold in most auto parts stores today. Solid core wire can be found at motorcycle shops and small engine repair places.

I'm one of those who use copper core wire and I solder it to the metal clip inside the boot to eliminate any possibility of a bad, loose connection.

Tom
 

crassius

Well-Known Member
Sep 30, 2012
4,032
158
63
USA
if you can't see a spark, take out the plug, hold it in your hand, put your hand on the motor - when you turn the motor over you will feel whether there is spark there
 

maniac57

Old, Fat, and still faster than you
Oct 8, 2011
4,484
22
0
memphis Tn
I got a handfull of cut-off plug wire boots free at my local auto pull-a-part yard. Just unscrew the stock wire from the cdi box and screw the new wire in. Mine actually runs a bit better after I changed it. Might be my imagination, but it seems to four-stroke less.