No ignition on cyl. 1 and 4 - TCI unit problem?

[thumperjsa]

Funny story. I was riding home one day and my bike started to run real crappy all of a sudden. No power, could not keep it idling without lots of extra throttle, you know the deal.

Got it home a sprayed water on the header pipes and found the 2 right cylinders were cold. So I put my thinking cap on and tried to figure out what could have knocked out one half.

Then it hit me that the only common item off of the top of my head for these two cylinders was fuel supply. Then I noticed that the vaccum line was pinched because the petcock was pounted towards the back instead of the front. Apparently the petcocks were intalled in reverse.

So I pulled the tank, removed the petcocks and swapped sides. Put the tank back on and viola', all was better.

I wish I could blame this on the PO but it must have been my fault. A month earlier I rebult the petcocks and must have got left and right backwards.

Oh well. You live and you learn.

[Lynge]

Common parts

That was a ceap repair. In my case it was cyl. 1 and 4 and the only common parts here is ignition, from pickup via TCI to coil.

I'm still working on the TCI unit (both power transistors changed and broken connections on the cirquit board fixed), but not yet up running :-(


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Jan H Lynge

1978 XS1100

[Shuriken]

How do you test the transistors to see if they are bad? After going through a similar mess, I might as well test them while I'm at it.

Ben

[Shuriken]

I'm guessing the OEM transistors are NPN type. I know what C is, just need to find out which is B and which is E. I've so far only tried to test the transistor in the circuit producing no spark and it initially seems fine.

Ben