No Spark on 83 TCI Bike

sentricity · Full Member Joined: Sep 09, 2007 Posts: 22 Location: NC

I desperately need some help here guys. I have had this bike apart and back together 10 times now trying to figure this out.

I had done a refresh on all gaskets and rejetted the carbs for the new aircleaners and punched out baffles on my 83 Hertiage Spec. The bike starter has been disconnected, the handlebar kill switch bypassed, the kickstand switch bypassed, new Mike's coil, new wires, plugs, boots, TCI transistor replaced, new battery....

I had the bike started and running three days ago. It was running rich and backfired out the carbs and died. I kicked it over and over with no luck. Pulled the plug and no spark. I replaced the plugs and replaced the transistor in the TCI box after messing with it for two days.

I have cleaned and checked all the grounds. Checked all the connections. Checked anything and everything associated with the ignition system and the charging system.

Question is, the two wires going to the coil are both hot when the key is on. 11.7v at the red and orange wires with the other lead grounded. I thought the red should be hot and the orange would not until you crank the engine over.

Short of completely rewiring the bike with a simplified harness, I don't know what else to do.

xsjohn · Posted: February 17, 2008, 12:59 pm Post subject: Re: No Spark on 83 TCI Bike

Have heard of the magnet on the rotor being a bit weak....probably not it...???

Did you check the ohm's on the pickup coil...??....three prongs........sideways one is common....should be about 700 ohm's between the common one and each of the two outside prongs........

Did you clean all connections and use dielectric grease......???

Weak battery...??

John

sentricity · Full Member Joined: Sep 09, 2007 Posts: 22 Location: NC

I checked the rotor 5.1ohms. Good.

On the pickup 721ohms on one prong and 707ohms on the other.

I have not scrubbed and cleaned every connection but they all look good. I'll do that now.

The battery is at 12.4v, that's good enough right?

sentricity · Full Member Joined: Sep 09, 2007 Posts: 22 Location: NC

I just retested the coil and the primary coil is reading 2.4ohms. good, but he secondary is reading 34.4ohms. That is too high. How could a new coil that ran just a few days ago test bad all of a sudden?

xsjohn · Posted: February 17, 2008, 1:49 pm Post subject: Re: No Spark on 83 TCI Bike

Sounds likeyoucould trythe old coil........mine has been pecking along for 52k........

John

sentricity · Full Member Joined: Sep 09, 2007 Posts: 22 Location: NC

I already trashed when I replaced it.

xsjohn · Posted: February 17, 2008, 1:56 pm Post subject: Re: No Spark on 83 TCI Bike

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John

sentricity · Full Member Joined: Sep 09, 2007 Posts: 22 Location: NC

Yeah I was already looking at them.

sentricity · Full Member Joined: Sep 09, 2007 Posts: 22 Location: NC

Other than testing that one transistor in the CDI box is there any other way to check if it's good?

xsjohn · Posted: February 17, 2008, 2:43 pm Post subject: Re: No Spark on 83 TCI Bike

Sure you won't like this answer.......a second tci..........

John

Retiredgentleman · Posted: February 17, 2008, 2:47 pm Post subject: Re: No Spark on 83 TCI Bike

The secondary winding on your ignition coil should be around 13,000 ohms??

sentricity · Full Member Joined: Sep 09, 2007 Posts: 22 Location: NC

Sorry it was 34.4Kohms, so 34,400ohms. My digital multimeter sometimes switches the ranges to be easier to read!?

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