Rear Cyl WILL NOT FIRE

[Odium]

I know this topic seems to have been done to death....and then some. I have gone through just about every fix I've seen listed on this forum for my problem, but can't seem to get it licked. At first my rear cyl would cut in and out and at the same time my tach would go dead. After a week or so, it just died completely. No more Tach, no more spark on the rear cyl. Replaced the plug, the wire, the coils. Went through and checked all the connectors again. Cleaned them and used dielectric grease on them. I replaced the fuse box with the modern slot type. Took apart the TCI. It looked ok, but that's as far as my check of it got.  At this point I'm ready to just yank the whole wiring harness and make a new one. Is it likely that it's just a bad TCI unit with the tach and ignition going out? Or more likely a wiring issue? Any help would be great. I'm getting rid of my main bike and the vision is now going to be my transportation. I need to get this thing on the road!

[YellowJacket!]

Odium,

I had the same problem.  Have you disabled the Rev Limiter circuit?  To do so, cut the yellow/black stripe wire at the TCI. (leave enough slack to reconnect it if neded)  It solved my problem.

David

[Odium]

that was the first fix I tried actually. No-go.

[Lucky]

I would check the safety relays & do a continuity/ohms test on the pick-up coils.  it might be if you've done a stator or starter clutch fix that there is some chafing or run thru of one of those wires.  carefully go thru the manual, section 7 (starting at page 13) on the ignition system. follow it carefully.

--Lucky

[silicon_toad2000]

you might have allready done it, but have you swapped out the coils, or even swapped the front/rear coil andsee if the problem follows the coil.

[Odium]

I have swapped the coils, and even got some replacements. Same result. I have not checked for shorts or worn wires at the stator though. I will check that tomorrow!

[Superfly]

When that happened to me, my TCI was wet.  You might have a TCI problem, do you have a spare?

Are you getting a spark to that cylinder?

[Odium]

I have no spark to the rear cylinder right now. I wish I had a spare TCI. I'm currently bidding on one on ebay. If anyone has a spare they can part with if I don't win the ebay auction, it'd be wonderful.

[Superfly]

On the 6-gang plug that goes into the TCI, take a pair of needle nose pliers, and pull out the black/white wire (you do not have to cut it, you can pull the connector out, so you can place it back later) this is the sidestand switch.  they have been known to go out also.

[jasonm.]

If you are losing just the rear... it IS NOT the safety relay or sidestand switch. These 2 item kill the TCI completely. I suspect the TCI is bad. I had one do the same. I took it apart. But changing the main transistors did not help. I even changed all the capacitors, still no good. On another I saw a crack in the board going to one transistor. This can be seen just by unscewing the removable cover.  Look carefully... The crack can be fixed with piece of wire soldered from point "A" to point "B" if you know what I mean.

[YellowJacket!]

What doesn't make sense though is that he swapped out the coils...or , did he swap them front to rear but leave them connected to the same harness?  Doing so would rule out the Cyl and point more at the TCI.

David

[Odium]

What I did was kind of dumb. I purchased replacement coils *just in case* then started testing the ones I had. You never know with these things. I swapped the existing coils front to rear. They had the same symptom so I swapped them back in place. So the upside is, I have a spare set of coils now if one goes dead down the road somewhere. I am still the high bidder on the TCI on ebay. It's sounding more and more like this should do the trick.

[Lucky]

good luck, i hope it's money well spent.

did you do the other tests in the manual while your waiting?

[YellowJacket!]

What I did was kind of dumb. I purchased replacement coils *just in case* then started testing the ones I had. You never know with these things. I swapped the existing coils front to rear. They had the same symptom so I swapped them back in place. So the upside is, I have a spare set of coils now if one goes dead down the road somewhere. I am still the high bidder on the TCI on ebay. It's sounding more and more like this should do the trick.

I did exactly the same thing.  Now I have a spare working TCI and coils that Im holding on to until I need them.

Good Luck.

David

[ozian]

As these TCI units get older more bad solder joints seem to come up. I think jasonm is on the mark. Run over the printed circuit with a meter to see if currant gets through where it should
Ian