83 xvz12tk running rough -TCI ? Only idles, barely.

[pmaier]

Didn't see any other posts similar to my issue, so here it goes.

 

Long story short, last summer moved the bike to new place. Garage was cluttered, so it sat outside for 2 days. Rain on one of them. After that, the bike would idle, but as soon as you tried to give it gas, it would act as if it were limited at 1500 rpm. When that happens, the tach drops to zero. Let off the gas, tach comes back. Didn't have time to ride last year so I left it.

 

Well it still does it. Pulled the battery out and looked at the connects on the TCI and they are dry and not excessively dirty or corroded.

 

New plugs and there seems to be spark on all 4 although the two rear plugs I pulled out were wet.

 

Any suggestions ? I have the shop manual and it basically says to check the resistance on the coils and if that's not it, replace the TCI.

 

I'm in Ottawa, Ontario, Canada. It's nice today and I'd really like to ride again. Please help !

 

Phil

[dingy]

The spark plug ends of the coil wires can get corroded, there is a small resistor in there.

 

Replacing plug wires would not be a bad idea if they are original.

 

Gary

[bongobobny]

Yah! If you are getting spark but the plugs are wet I'm thinking your spark is not hot enough. Also pull the plug wires from the coil and make sure there is no corrosion in the coil end. What bothers me, though, is the fact the tach dies. The tach is fed by the primary pulse to coil 2. You may want to take your TCI out, remove the cover and swee if any water comes out of the case. Then bake your TCI in an oven at around 225 - 250 degrees Farenheit for a couple of hours to bake out any moisture whether you get water coming out of the case or not. In Canadian degrees it's anything slightly above 100 degrees C...

 

Besides the plug wires, try new plugs as well. They might look all right but might not be good enough.

[Rocket]

After that, the bike would idle, but as soon as you tried to give it gas, it would act as if it were limited at 1500 rpm. When that happens, the tach drops to zero. Let off the gas, tach comes back. New plugs and there seems to be spark on all 4 although the two rear plugs I pulled out were wet.

 

Any suggestions ? I have the shop manual and it basically says to check the resistance on the coils and if that's not it, replace the TCI.

 

Phil

 

I had similar a few years ago, but it was a loose #2 coil primary connection. Check those connections, you may possibly have 1 or 2 loose ones. These engines run surpisingly good on 3 cylinders......

[Marcarl]

Seafoam!!!!

[pmaier]

Seafoam!!!!

 

I suppose u mean for the electrical connections.

[Rocket]

Seafoam!!!!

 

I suppose u mean for the electrical connections.

 

Nope, seafoam is for the carbs, pour some in the tank & run the bike.

[Gdserlin]

http://www.venturerider.org/forum/showthread.php?t=49023&highlight=coil+connection

 

 

also do a search under "coil connection"

[MiCarl]

The tach cutting out is not from carburetors. The tach gets its signal from one of the coil primaries. The TCI is dropping that coil so the tach has nothing to read and goes to 0.

 

My 89 will do exactly the same thing if I get crazy with the hose and get a bunch of water above the engine. After a short (poor performance) ride it'll dry out and is fine again. I have not got round to sorting it out.

 

My guess is that something (perhaps a connection, maybe inside the TCI) is getting partially shorted by the water. It works fine at idle but as things speed up the components need to react faster and there is enough loss from the short that the voltage isn't there to move things fast. My best guess is that this is between the TCI and pick up coil.

[pmaier]

So to give an update. All connections on the coils and the TCI looked dry. Took out the TCI and cracked the case, looked dry, but put it in the oven as recommended anyway.

 

Measured the resistance according to the shop manual on the coils and the results are as follows:

 

Primary coil (should be 2.7ohms +- 10%)

cyl 1 - 3.1

cyl 2 - 3.1

cyl 3 - 3.1

cyl 4 - 3.2

 

Secondary coil (should be 13.2 kohms +- 20%)

cyl 1 - 11.96

cyl 2 - 12.40

cyl 3 - 12.40

cyl 4 - 12.10

 

Plug Wires (should be 10 kohms +- 10%)

cyl 1 - 5.04

cyl 2 - 4.59

cyl 3 - 4.34

cyl 4 - 4.57

(note all the plug wires appears low, but they are all similar. The plug wires do look original.)

 

Does the above seem to ring true or false to anyone ?

 

Once I finish baking the TCI module, I'll assemble the bike and let you know the results.

 

Phil

[dingy]

So to give an update. All connections on the coils and the TCI looked dry. Took out the TCI and cracked the case, looked dry, but put it in the oven as recommended anyway.

 

Measured the resistance according to the shop manual on the coils and the results are as follows:

 

Primary coil (should be 2.7ohms +- 10%)

cyl 1 - 3.1

cyl 2 - 3.1

cyl 3 - 3.1

cyl 4 - 3.2

 

Secondary coil (should be 13.2 kohms +- 20%)

cyl 1 - 11.96

cyl 2 - 12.40

cyl 3 - 12.40

cyl 4 - 12.10

 

Plug Wires (should be 10 kohms +- 10%)

cyl 1 - 5.04

cyl 2 - 4.59

cyl 3 - 4.34

cyl 4 - 4.57

(note all the plug wires appears low, but they are all similar. The plug wires do look original.)

 

Does the above seem to ring true or false to anyone ?

 

Once I finish baking the TCI module, I'll assemble the bike and let you know the results.

 

Phil

 

You should be in the working range on what you posted. Assuming you did not show the K ohm symbol in your bikes readings.

 

Plug wires are a little low, but if anything that should help develop more of a spark.

 

Have you checked the pick up coils?

 

They should each be in the 93-126 ohm range.

 

The schematic in the manual has an error in color codes for the pick up coils.

 

Here is a link to the schematics on this site.

 

http://www.venturerider.org/forum/showthread.php?t=42358

 

 

This link is to the specific one for the 83 model.

 

http://www.venturerider.org/wiring/83%20Yamaha%20Venture%20Royale%20TDK%20Wiring%20Diagram%20Rev%20C.pdf

 

Gary

[bongobobny]

The coil wire primary and secondary readings look about right although near the edge of spes. A bad coil will be waaaaay out of line with the rest of the coils. Some ohm meters may read a little off from others depending on make and battery level.

 

Unless you bought new wires, it may be time to consider a new set! They don't last forever...

[pmaier]

So I put the TCI module back in and fired it up. Same result as before.

 

Next I checked the pickup coils. I took 4 readings as I wasn't sure if there are actually 2 coils with 2 windings or 4 coils. Below are the wire colors and measured resistances.

 

O to B wire = 116.4 ohms

Gy to B wire = 116.8 ohms

W/G to B wire = 124.4 ohms

W/R to B wire = 116.6 ohms

 

The range is supposed to be 93.5 to 126.5 ohms. These readings seem ok to me.

 

So, what next ? Any ideas ?

 

Phil

[bongobobny]

There are two pickups with shared center taps on the coils, for technically 4 coils. The schematic lies in the TM, if I recall right. I think the Black should be the common center tap, not the orange. You should see 4 separate coil readings approximately the same, andf 2 sets of wires where you read twice the resistance. Next test your boost sensor (Vacuum moduloe next to the TC!. With 12 volts applied you choulod see around 2.5 volts. If you, have a vacuum pump you should see the voltage change as you draw vacuum.

 

Because you say the tach drops out I'm hesitant to blame carbs yet, but not to say with the age of the bike and not being run for so long, I'm not entirely ruling them out. You need to try a different TCI if you can, there are diodes in there that can $hit the bed. Also, coils can be intermittant...

Edited May 15, 2011 by bongobobny

[bongobobny]

Where in Ontario are you??? I may be able to lend you a TCI and/or a coil pack to herlp troubleshoot...

[pmaier]

I'm near Ottawa, Ontario. About 300 miles from Arcade, NY.

[pmaier]

Taking the bike into the dealer tomorrow.

 

If it is the TCI module, how much do these things go for ?

 

Am I better off getting an e-bay module or that one from overseas that is programmable ?

 

Has anyone got one that works for sale ?

 

Phil

[painterman67]

my 91 did the same thing. no tach and ran like crap...........ended up getting a new to me tci/cdi off of ebay. all is well. New tci/cdi from dealor was going to cast 999.95. Good luck as i got lucky and found one on ebay mislabeld and got it for less than 40 bucks shipped to the door

 

 

David

[dingy]

Taking the bike into the dealer tomorrow.

 

If it is the TCI module, how much do these things go for ?

 

Am I better off getting an e-bay module or that one from overseas that is programmable ?

 

Has anyone got one that works for sale ?

 

Phil

 

In my opinion, I would get the new one from Ignitech. Under $200 shipped. You will want to make sure they ship some extra wiring harness pins when purchased. This is to add vacuum sensor.

It takes a little work to get it set up, but you are getting a new piece of equipment. Whatever you get from Ebay or any where else might fail the next day.

Here is the main thread dealing with this unit.

http://www.venturerider.org/forum/showthread.php?t=40414

There are probably 10 or more of us that have this unit, and I know of no major problem.

The wiring for the most part is done with an adapter they supply. Other main thing that needs added is a vacuum sensor. Not real hard to do.

A PC (laptop) is needed that can be hooked up to the module once installed. It has a 9 pin serial port connector. If PC doesn't have a serial port, Radio Shack sells a USB to serial adapter for $25 or so.

Gary

[mrich12000]

If you need a coil set complete I have one in great shape I was going to put it in my Venture 1983 1200 But I sold the bike and now have a V-Star 1300 tour. so It's taking up space price is very resonable.. Michael..

[Ottawa]

I'm near Ottawa, Ontario. About 300 miles from Arcade, NY.

 

PM me and we can talk soon.

[pmaier]

I ask because I got a used one at a local salvage and the bike doesn't run at all. With mine, it just runs poorly.

 

Can I use a TCI from 84+ on an 83 ?

 

Phil

[dingy]

I ask because I got a used one at a local salvage and the bike doesn't run at all. With mine, it just runs poorly.

 

Can I use a TCI from 84+ on an 83 ?

 

Phil

 

You can use a TCI from 84-89 on the 83.

It will require the vacuum tube that goes to the #2 carb (LF) to be moved to the intake manifold port & the existing port on the carb body plugged.

Gary

[pmaier]

Without the vaccum changes, the module should run though, right ?

 

This one doesn't fire at all.

 

Is there a way to test a module ?