New Guy with my first xs650 project

If you are trying to do this on the cheep then a Banshee and Pamco with the rod and advance weights are going to cost some. Here is an extract from the old 650 rider forum i saved if you want to check and repair your TCI

T1D12-01 3G1 is an 80

T1D12-01B 4M4-10 is an 81

If you suspect your TCI unit may be bad, you may
not need to buy a new one.
I am going to tell you how to fix it.
Parts #s where to buy, everything. And for less than $2!
Read below.
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I own a 1983 Yamaha xs650 Heritage special
the bike was acting funny sometimes, almost like it was
going to run out of gas sometime even when the tank was full.
Sometimes it would even stall on me driving down the road.
I tested the alternator, the rectifier, the coils, everything tested fine.
The last place was the TCI unit.
My TCI unit is labeled TID12-03 5V4-10
how do you test that?
________________________________________

The 2 most common problems with a TCI unit are:
1. Loose or bad solder connection somewhere on the board
2. Bad transistor.

After checking all the solder joints I started testing and replacing the transistor.

Here is how to test:
________________________________________

The transistor is a chip that is attached to a shiny aluminum heat sink
and has 3 prongs that attach to the board that are labeled C,B, and E
Collector, Base, and Emitter

With a multi meter set to diode test >|
(diode has the symbol of an arrow pointing at a line)

Place the negative probe on the B and the positive probe on the C,
you should get a 1 reading meaning no conductivity

Now switch the probes (negative on C, positive on B)
you should get a 0 reading (or something other than 1)
meaning conductivity

Do the same thing with the B prong and the E prong
you should only get a 1 reading meaning no connectivity
when the positive probe is on the E prong


The transistors on xs650s are type NPN.

Description: NPN Transistor Diagram of Transistors used in xs650 TCI boxes



If you get reading that conflict with the tests above, or if you are unsure,
replace the transistor. It costs less than $2 at radio shack.
The part # is 276-2068
Here is a link:
www.radioshack.com/pro...age=search

The description is TIP120 NPN-D Transistor

Just unscrew and unsolder the old transistor and solder and screw in the
new one. Its a direct replacement.

After switching out the transistor on my bike, not only did it work again, but it felt stronger and now never falters!!

There are TCI boxes on eBay right now all for around $100
Hopefully my experience will save some people some hard earned
money. I know I did!

Good luck.

Josh Connon
Columbia,MO

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t_tst_f5.gif
Description: NPN Transistor Diagram of Transistors used in xs650 TCI boxes

Note:
I couldn't get the diagram to transfer, (wrong format), so here is a link to the post
TCI Repair





Footnote: Pamcopete on the type of resister to use.
I listed two better candidates to replace the transistor in the TCI:

Motorola MJE5742 (TO-220 case)
Motorola MJH10012 (TO-218 case)

Probably the MJE5742 is a closer replacement and at least one other member has said the same thing with the same recommended transistor.

To test the pickup
ohm out the pick-up and pass a magnet over the face of it, the readings should change. If they do, it's good.

Q: I did the checks as prescribed in this thread. I ordered a new transistor and hope to have this bike running soon. I have a question on timing. Which is the best way to set the timing on a transistor (Electronic) 1983? I have replaced two pistons and realigned the timing chain properly. Which piston is conceding red number 1? I put the top dead center with left piston seating on the bike. Is that proper? The bike fires but won't start

A: I use a timing light hooked to the left plug. Check if it flashes on the F on the rotor at 1200 rpm. If it is real close that's ok. If it is way off then you will have to grind off the break off screws on the pickup coil and put screws in their place to set the timing. If you can't get it running to check it I am at a loss to help. Bet it is not the timing if you haven't changed it. Starting spray may help.

The early electronic ones had 6 pin connectors.....later they added the side stand no spark function......never had any problems with mine so don't know if they are interchangeable.....I would suspect they are somehow...

Just an option
 
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The best way is with a timing lite & the manual. I got mine set to about 1/8" from the 'F' mark at 3000 rpm. No problems starting, running, or performance. Starting off from lite's also no problems. And I weigh in @ 200lbs.
You will have to replace the screws that hold the pick-up to the stater, as the factory had screws that snapped the head off when torqued to spec.No biggie, available almost anywhere.:bike:
 
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