Bad CDI?

GoldenMotor.com

geoldr

New Member
Jun 19, 2011
260
0
0
California
Hey guys, When I was putting on the CDI to the bike, the wire came out. The wire from the box to the plug came out on both sides. Does that mean this CDI is junk and I should get a new one? I tried just putting it back in, and plugging in the stock spark plug, but of course, there is no spark. What should be my next steps to diagnose the problem?
 

DuctTapedGoat

Active Member
Dec 20, 2010
1,179
10
38
38
Nampa Idaho
Get a new wire core spark plug cable, it just threads right on into the box and boot.

Though, you shouldn't need a new one - just trim the end like, half an inch off both sides and screw it back on.
 

geoldr

New Member
Jun 19, 2011
260
0
0
California
I went to sick bike parts and ordered the high performance plug wire along with a couple of NHS BP6HS spark plugs. I was testing the motor today, and the magnet spins fine, I connected LED light to the blue&black cables and the light lit up. After examining the spark plug cable, it was just a piece of junk. I don't see how it could have worked, so hopefully after this new stuff comes in the mail I can get going!
 

Venice Motor Bikes

Custom Builder / Dealer/Los Angeles
Mar 20, 2008
7,271
1,810
113
Los Angeles, CA.
It's possible that if the spark plug wire came off while riding?, that could've burned out either the CDI or the magneto.
I know that if the main coil wire on a MSD ignition comes off while driving, the MSD box will fry because the spark thats generated has nowhere to go.
 

GearNut

Active Member
Aug 19, 2009
5,104
11
38
San Diego, Kaliforgnia
It's possible that if the spark plug wire came off while riding?, that could've burned out either the CDI or the magneto.
I know that if the main coil wire on a MSD ignition comes off while driving, the MSD box will fry because the spark thats generated has nowhere to go.
CDI ignitions are quite prone to this kind of failure too.
 

geoldr

New Member
Jun 19, 2011
260
0
0
California
It didn't come off while riding, because I haven't riden it yet. When putting on the cdi I examined it and the cable just looked like junk. I decided to order a new cable and spark plug. Should be here tomorrow, andhopefully it all works.
 

DaveC

Member
Jul 14, 2010
969
1
18
Boise, ID
That's on the list of things to do before the first ride. Those sparkplug wires and especially the boots are junk. The Chinese make from 6 parts something we make from 3. I suspect the boots are made in a toy factory. And they break like Chinese toys.
 

Al.Fisherman

New Member
Sep 9, 2009
1,966
5
0
Calera, Alabama
I hate to have people go online and but one at a inflated price and then pay shipping. Best and the most inexpensive is 1. Cut one off of a lawnmower, edger or the like. 2. Can be bought at a lawnmower repair shop. The plug from Auto Zone. Advance or stores like that. Hate that you ordered one.....
 

DuctTapedGoat

Active Member
Dec 20, 2010
1,179
10
38
38
Nampa Idaho
So, I picked up the fibreoptic style - it works well, but it doesn't stay screwed down at all. Gonna have to find a way around that without glueing it...