Raising the dead

[Pegasus]

I am trying to resurect my '81 XS1.1S which I've owned since '89 which has been in storage for three years. I'm getting a minimal spark from the LH coil leads and none from the RH coil, inspite of a thorough electrical check and new coils. Could it possibly be the TCI unit? I can't find any info on symptoms or testing. Any advise would be appreciated.

[strom]

Check out the tech tips section.
I'd use some WD40 on all connections... liberally... and check the pick-up wire fix. And your battery.

LP

[Pegasus]

Thanks Strom, battery OK, pick-up wires checked, coils renewed, plugs renewed, all fuses checked, starter switch cleaned, power getting to coils at 11.5v. The only unusual thing I can find is a zero voltage reading at the black/white wire connection between the emergency cut out (which checked OK) and the TCI which joins at the large connector. My Haynes manual says this should read 6 volts. Also the bikes earth reads 0.6ohms not zero. One other thing my bike doesn,t have a ballast resistor or any connections for one. Any ideas?

On a general note - Yamaha UK want a strictly non-refundable $935 for a replacement TCI unit (which presumably has been lying in some store since the eighties).

[TopCatGr58]

Hey there Pegasus,

Well, first you could try swapping the coil primary plugs so that the TCI would be controlling the "other set", pull all the plugs so it doesn't strain your starter motor, and then put spark plugs in the ends of the coil secondaries and turn it over and see if the "Bad" coil now gets good spark. That will help to further eliminate the ignition coils!

The pickup coils can test good when static, but upon rotation of the vacuum advance and flexing of the wires, they can then exhibit the intermittent connection symptoms. Did you actually do the pickup coil wire stretch test!? The 81's don't have Ballast resistors, they use different coils rated at 3ohms, vs. the earlier models of 1.5ohms!

The black and white Emergency cutoff wire is just connected to ground when activated. My clymers doesn't even have that much info on how much voltage should be from each connection!? It apparently controls a switch inside the TCI which turns power off to it! Your ground is 0.6ohms, how and where are you measuring that? Are you talking about the ground wire as part of the connector for the TCI?

Well, that NOS TCI is only about $850 overpriced!!!! There is a guy here on the Forum that's fixing these things, I don't know how well he will be able to diagnose this later version vs. the 78-80 2H7 series he's worked on!? Many folks have found bad/cold solder joints inside their TCI's where they connect to the external connectors. After you have ruled out the other possibilities, main coils, pickup coils, then you've got nothing to loose, but to open up the TCI and check it for broken joints, and possibly resolder them!? Or you can contact IIRC Randy and see about shipping it to him for repair!?

I've got a working spare for an 81, but that's the problem, it's my only backup for if/when mine craps out! Sorry! HTH.
T.C.

[pgg]

Another check - the plastic pin connecter behind the fusebox that joins the pick-up wires - might have grungy contacts. I swapped that pin plug to screw connecters after similar troubles.

[Pegasus]

Thanks for the help - I moving on gradually, I rechecked all connectors (inc, those in behind the fuse box) and double checked the pick-up wires, I now have a weak spark at all four plugs.

[Pegasus]

Hi, No luck starting the beast yet though it looks brilliant as it's never been so clean - all system readings OK, all connections checked, I presume the really, weak almost non-existent spark at all plugs even with a fully charged battery is due to the TDI unit as I have double checked everthing else, but is there a way to test the unit to be sure?

Reconditioning or replacement is really expensive in the UK does anyone know where I can get a spare TDI Unit (Hitachi TID14-04 4R0-10) or can you advise where I can get this one reconned?

Pegasus

[Pegasus]

Its Alive!!!

After trawling the site for info on weak sparks - I found a tip from Buffalo of Bellefonte, PA who suggested cleaning the main earth connections (from the engine to frame) and guess what! Nice spark on all plugs, stuck the tank on and away she went first hit of the button!!

I guess the lesson is don't rush to blame the hi-tech bits before you check ALL the basics. Thanks guys - a truly great site I couldn't have done it without your help.