TCI box differences

[xschris]

I have a bunch of 80-82 sohc TCI boxes that I have picked up over the years ( five of them) and decided to open up an 80 and a 81-82 (sohc) as the 81-82 one look to have a different number on it (the one on top). I was suprised to see they looked much different inside I know on most bikes and cars the first years are always the worst and has the most issues. I wonder if the 80 TCI boxes where more restrictive on timing or something to do with the new emissions. All I know is the 81-82's are much more simple with a lot less bits inside I will have to hook up the newer boxes to the bike and see if it runs any better

 

[Scorpio1963]

I don't have a clue but but there sure is a lot of electrical components on the bottom one in your pic.

 

[TOUGEFC]

My Aus spec 80 is the same as the top box you pictured xschris,
Are they interchangeable between the two?

 

[xschris]

Yes you can run them with any sohc xs400 setup for electronic ignition. I am running the 81-82 box on my 80 now.

 

[Wolfe_11B]

One looks to be a single sided PCB. I bet the other is exactly the same, just has more components on the other side (double sided PCB).

 

[xschris]

Nope it is one sided. I took another one apart.

 

[Wolfe_11B]

Wow that's quite simplified. They really cut back the number of diodes.

 

[xschris]

Usually the second generation stuff is better and less complicated. In this case less is more

 

[Scorpio1963]

What year is the 2cnd box from looks very similar to mine.

 

[xschris]

I have a bunch of 80-82 sohc TCI boxes that I have picked up over the years ( five of them) and decided to open up an 80 and a 81-82 (sohc) as the 81-82 one look to have a different number on it (the one on top). I was suprised to see they looked much different inside I know on most bikes and cars the first years are always the worst and has the most issues. I wonder if the 80 TCI boxes where more restrictive on timing or something to do with the new emissions. All I know is the 81-82's are much more simple with a lot less bits inside I will have to hook up the newer boxes to the bike and see if it runs any better

In the first post

 

[FarmBoy72]

I have the more complicated one on my 78 (came from an 80). Before I switched away from points I replaced all the capacitors in it. fires dead on now! jumped around a few degrees before.