Misfire and Tachometer dropping...

[kbert777]

Maybe somebody can help me troubleshoot this, before I tear the whole bike apart. 89 1stGen with about 75k miles, pretty much stock. Was sitting for about a year (due surgery and work load), had fuel stabilizer in tank. Flushed carbs, changed oil and spark plugs, checked air filter and went for a nice 200 mile ride this morning. Bike was running OK, little bit of an engine vibration, wanted to run a few tanks of gas through before adjusting carbs. About 130 miles into the ride I start seeing the tachometer dropping to Zero for a second or so, then it recovers, no loss in performance. After about another 20 miles the tachometer drops more frequent and for longer periods of time, now the engine stumbles and it becomes hard to maintain a steady speed. I pull over to the side of the road and idle is rough, tachometer is more at zero then anywhere else and exhaust is popping and I can hear some misfires. Made it home the last 40 miles, almost used 3/4 of a tank of fuel, bike was running best above 5000 rpm.

 

Anybody ever been through this particular problem? At first I thought a bad spark plug, but that would not make the tachometer drop out completely? So that would leave TCI or pickup coil, maybe some bad connections or a bad coil?

 

I have a spare TCI I never tried, maybe it's time to relocate it and check the connections...

 

Any input welcome, thanks in advance.

 

Klaus

[bongobobny]

Most likely TCI or connectors. The tach uses ignition signal from TCI cyl 2 if I remember right. May be moisture in TCI or corroded connector...

[pmelah]

yes im going thru it now i now have a no spark condition i cant figure out and my bike is 34 mies away in a parking lot so cant tell you much more other than my old tci died put new tci in and changed plugs nnow its no spark check your connectors clean them and check coilsthats all i can tell you for now

[kbert777]

I kind of thougt that it's TCI related; is this something a diode replacement would cure or is it past that point? I have a spare I have never tested, will see tomorrow if this fixes it.

 

Klaus

[pmelah]

if its still running then it should do the trick but check your coils to to be on the safe side as your tach gets its signal from # 2 coil and if you haven't changed the diodes in the spare i would do that one too but this is all still a learning experience for me only its the hard way also bake your tci in the oven at 100 degrees for 30 min it will cook all the moisture out witch is bad and i recommend reading the tech library section there is detailed instructions in it on what to check and how to check

[Flyinfool]

It is common to find water inside of the TCI. For some reason there is a hole in the case to let water in but not out. If it is moisture causing the problem sometimes they can be dried out and saved. Once damage is done it is to late to do the diodes.

[kbert777]

Thanks for all the comments, living in Las Vegas, moisture is usually not a problem around here. Right now it's 100 deg and about 10% humidity. I pulled my spare TCI and it has a different number then the one listed in the manual. What years are interchangeable and does anybody have a list of the corresponding Hitachi numbers? I am almost tempted to buy a brand new one, but I would have to assume that most of the replacements have been sitting on the shelf for a long time, cheapest I found is around $500. I know there is the Ignitech options, but I don't know if it's worth playing around with.

 

Klaus

[pmelah]

Thanks for all the comments, living in Las Vegas, moisture is usually not a problem around here. Right now it's 100 deg and about 10% humidity. I pulled my spare TCI and it has a different number then the one listed in the manual. What years are interchangeable and does anybody have a list of the corresponding Hitachi numbers? I am almost tempted to buy a brand new one, but I would have to assume that most of the replacements have been sitting on the shelf for a long time, cheapest I found is around $500. I know there is the Ignitech options, but I don't know if it's worth playing around with.

 

Klaus

 

i recommend the Ignitech that member dingy sells for 260.00 you cant go wrong and he pretty much has all the bugs worked out and helps you out with any problem you do have with it

[kbert777]

I think I am pretty much screwed with the original TCI. I removed it from the stock location, checked the connectors, pickup coils and ignition coils. Everything was within specs. The spark plugs are new, the wires and caps less the 1000 miles in.

 

I opened the TCI and it has some heat damage to one of the output transistors, also the diodes are the failure prone blue ones. Problem is that my spare TCI has a different number. The old one is TID13-43 1FK-09 0711 (yellow sticker), the spare one is TID14-34 41R-09 0204 (blue sticker). I can not find any reliable information what year the spare on fits, so I am hesitant to even plug it in.

 

I PMed Garry to see if he has an extra Ignitech unit available, in case that does not work out, does anybody have a known good on suitable for an '89 he is willing to sell?

 

I am taking the down time to finally fix the fuse box issue, also have a really weak front brake, still would like to get some riding in before it gets too hot around here.

 

Thanks in advance,

 

Klaus

[Prairiehammer]

 

I opened the TCI and it has some heat damage to one of the output transistors, also the diodes are the failure prone blue ones. Problem is that my spare TCI has a different number. The old one is TID13-43 1FK-09 0711 (yellow sticker), the spare one is TID14-34 41R-09 0204 (blue sticker). I can not find any reliable information what year the spare on fits, so I am hesitant to even plug it in.

 

The 41R will work on 1984-1989 Ventures. Blue label

The 1983 uses the 26H TCI. Black label.

1990-1993 use 3JJ TCI. Yellow label.

But, don't get fixated on the label color, time and heat might change the color a bit.

The 1FK sounds like a V-Max number. And it worked in your '89 until recently? Hmmm.

Edited June 3, 2013 by Prairiehammer

[JohnMidnight]

To the OP

 

Its your TCI.

 

Mine gave me all sorts of heart ache like that last year. She'd be fine for the first 100 miles them bad, it'd start. Then get worse, then hit the point where she's done, and needs tow, or sit around for a few hours start her back up just fine and get home.

 

my fix was a Ignitech.....

 

I've got my original TCI, and two other TCI in my storage locker. I wont be going thru town again till tomorrow, I'll swing by and pull them from the locker, check em out, and give a headsup incase you need one

[kbert777]

Thanks Guys for all the responses, looks like my problem is the TCI, I also found a bunch of pretty dirty connectors. Ended up cleaning the connectors and packing them with dielectric grease.

Ultimately I bought an Ignitech Kit from Gary, probably going to run it so that in case of emergency I can still plug in the original TCI and boost sensor.

Pretty busy at work right now and I still plan on replacing the fuse box. Going to be a while until bike is back up and running again, probably going to start reassembly next week.

 

Klaus

[GeorgeS]

Be sure to inspect the " Plug " in the cable running " from " the " Pick Up " coils, that runs to the TCI.

5 small wire cable, has a plug, about half way from pick up coils to the TCI.

 

Its located just about under your left knee, as you sit on the bike.

This plug has caused problems, clean the pins, and tug tug on the wires on each side of the plug. Might be a loose wire, at a crimp.

 

Also, check the Plug, on the " Barometric Pressure sensor "

 

Also, don't forget to do a Resistance Check " thru the Run Stop Switch "

[kbert777]

The 41R will work on 1984-1989 Ventures. Blue label

The 1983 uses the 26H TCI. Black label.

1990-1993 use 3JJ TCI. Yellow label.

But, don't get fixated on the label color, time and heat might change the color a bit.

The 1FK sounds like a V-Max number. And it worked in your '89 until recently? Hmmm.

 

Yes, funny thing is that is worked and has been in there for at least the 20k miles I put on the bike since I owned it. Always had a few problems getting the idle right and gas mileage never went over 33-35mpg, let's see of the Ignitech unit makes any difference.

 

Be sure to inspect the " Plug " in the cable running " from " the " Pick Up " coils, that runs to the TCI.

5 small wire cable, has a plug, about half way from pick up coils to the TCI.

 

Its located just about under your left knee, as you sit on the bike.

This plug has caused problems, clean the pins, and tug tug on the wires on each side of the plug. Might be a loose wire, at a crimp.

 

Also, check the Plug, on the " Barometric Pressure sensor "

 

Also, don't forget to do a Resistance Check " thru the Run Stop Switch "

 

Actually, that's the first connector I checked and I was amazed how bad it looked. Everything ohmed out OK and I cleaned a lot of connectors in the process, everything is nice and clean and filled with dielectric grease,

The more I look at it, I might add an override switch for the run switch and side stand switch, just for diagnostic purposes, maybe just a push button.

 

Klaus