New Diodes in Stock TCI

[Yammer Dan]

Is #2 cylinder still firing?

 

If it is, it will probably still work.

 

Also, the fuel pump is triggered of off #2, if bike is still in running, I would suspect another problem with tach.

 

Gary

 

 

 

Tach drops to zero. Put spare TCI in and tach works. Swap back to orginal TCI tach drops to zero. Bike runs. Seems to run OK. Only way this thing runs as good as I would like it to is WTFO.

[dingy]

Tach drops to zero. Put spare TCI in and tach works. Swap back to orginal TCI tach drops to zero. Bike runs. Seems to run OK. Only way this thing runs as good as I would like it to is WTFO.

 

 

Do you know if the fuel pump or tach wiring has been modified ?

 

Per the wiring schematic, which may not be correct, the tach & fuel pump should live together & die together if #2 is firing or not.

 

As in firing, I mean getting a signal from the TCI. The coil could go bad & #2 would not fire, but tach & fuel pump would work.

 

Gary

Edited August 20, 2010 by dingy
added last line

[Yammer Dan]

Pretty sure it is as came from factory. I knew this bike for a few years and it ran like a dream til I got it. Skid said it don't like being outside under a cover. It just don't like me.

[JoeKanuck]

I thought it was about time to give a progress report on my bike. I have put almost 3000 kilometers on it since I repaired the diodes on my TCI. So far, it has worked without a hint of problems.

 

I am sure that there are probably other potential issues that could crop up with a 25 year old bit of electronics, but I feel much better about the TCI after replacing the diodes.

 

If you are a dab hand with a soldering iron or know someone who is, it is a reliability option I can recommend.

[Yammer Dan]

I just wish I understood 1/2 of this.... Changed out TCI on mine and it finally seems to be doing Great.

[jasonm.]

I will check my diodes...eventually. But I know the Barrel original diodes that Yamaha used are a usually "higher" current rated diode when compared to the 4000 series. 3 amp vs. 1 amp. So I would likely do it with something . I will get from Radio Shack just like the originals. I know they have the 3 amp type.

Edited October 6, 2010 by jasonm.

[bkuhr]

I will check my diodes...eventually. But I know the Barrel original diodes that Yamaha used are a usually "higher" current rated diode when compared to the 4000 series. 3 amp vs. 1 amp. So I would likely do it with something I will special order from Radio Shack.

 

I thought the same thing when I did my TCI, so I bought both:

"pkg of 25 assorted 1 amp recifier diodes" radio shack #276-1653 $2.79

and

4 pkg of 2 "1N5402 3amp 200V recifier diodes" radio shack #276-1143 $1.59/pk

Both items stocked in store-no need to special order.

 

When I got the TCI open, I realized 3 amp diode was way over kill,and would require redrilling pcb holes for larger diode lead diameter, and the "pack of 25" included at least 8 of the 1N4001 others have called for-so this is what I used, and no problems since.

 

BTW- if still interested, I still have the 1N5402's, 4 unopened packs of 2.

[JoeKanuck]

The 1N4001 diodes in mine have been running perfectly for over 3000 kilometers so far. I can't imagine needing much more of a torture test than that to prove the concept.

 

There are probably other potential failure items in a 25 year old box but I'm not worried about the diodes.

[JoeKanuck]

So it has been almost 3 years and my bike has been ticking along without a hickup. I think I can conclusively say the fix has worked and I consider it a screaming success.

 

I recommend it to anyone who has an old TCI, because I'll pretty much guarantee that those diodes are on the way out, and if you catch it before they fail, I strongly suspect that you'll have as much success as I did.

 

If you're not that keen with a soldering iron, I imagine an electronics tech would do the job for less than 50 bucks.

Edited May 31, 2013 by JoeKanuck

[pmelah]

hey Joe what do you think about these diodes :whistling::confused24: i think beyond saving this tci

[JoeKanuck]

I'd say those diodes are just about toast. That being said, as long as your TCI is still working, then it can probably be saved.

 

You're not screwed until the diodes cause a problem in another component...and there's no telling what a bad diode can fry.

 

Since you already have it apart, I'd say get the diodes replaced and give it a try. My diodes were in about the same shape but my TCI was still working....and it's still working after the fix...3 years later.

 

Visually, I couldn't tell if any other components were ready to go, but they all looked good.

 

Once again, if you're not really handy with a soldering iron, get someone else to do the job. The conductive layer on the board is a bit delicate and there is a chance of lifting or breaking traces if it's done wrong...which isn't a deal breaker if you know what you're doing.

 

I'm no expert but I have done my share of soldering, so it was a fairly straightforward job.

[pmelah]

My tci died squidley sent me his spare to use for now but im stuck in advance auto parking lot yrying to figure a new problem oit I have no spark to any plug and I just changed them in the parking lot they are all gapped between 31 and 35 squidley is racking his brain on this now while my nattery vharges I killed it tryin to vrank it fuel pump runs to

[dingy]

hey Joe what do you think about these diodes :whistling::confused24: i think beyond saving this tci

 

That one is probably dead. The 2nd picture shows real bad diodes.

 

If it is cranking, but no fire on any cylinder, then try jumpering around the ignition fuse (in emergency) and/or signal fuse. Both should be 15 amp fuses in main box.

 

Gary

[Squidley]

That one is probably dead. The 2nd picture shows real bad diodes.

 

If it is cranking, but no fire on any cylinder, then try jumpering around the ignition fuse (in emergency) and/or signal fuse. Both should be 15 amp fuses in main box.

 

Gary

 

 

Gary,

 

He has one of the ignitec's in the bike now, the one I bought from you that was in Tweety. The bike just up and died and I'm steering him towards the side stand switch and how to jumper it to bypass it.