No spark to one cylinder, 1986 VR

[ahunt2412]

Has anyone ever experienced a faulty key ignition causing "no spark" to one of the cylinders?? I thought I had a bad TCI but I tried another and I had the same problem.

I fiddled with the key (sprayed a little WD-40 in the key slot) - worked it back and forth a couple of dozen times and suddenly got spark!

 

The bike has kind of been driving me crazy with the lack of spark to that cylinder - then - suddenly spark again... Just wondering if the bad key ignition could cause that symptom or not - best to ask the Venture specialists here on the board.

Thanks in advance

[Yammer Dan]

I thought the Ignition was either off or on. You had spark or not with it. Couldn't go to just one or three cylinders.

[FROG MAN]

You probably got a bad connection on the pickup coil connector.

[mbrood]

The ignition switch CAN get funky but it's an either go or no go for everything.

 

When it drops the spark... check for +12v on pins 2, 3, 6 and 7 at the TCI (yeah, just pull the plug and measure with the key on)... this goes from the battery, through the primary of the ignition coils to the TCI. While there, make sure that the pins on the TCI are clean and the ones in the white plugs are as well as all spread the same.

 

With the ignition off, measure the resistance from the ignition fuse to each sparkplug cap... you should read 23K Ohms... 13K for the ignition coil secondary and 10K for the resistor in the plug cap... much more and one end of the high voltage ignition wire is corroded and needs a short bit clipped and reattached.

 

 

http://www.bergall.org/temp/venture/tci/tciplugs.jpg

[Venturous Randy]

Had a similar problem on a friend's 89 and it ended up being a corroded resistor in one of the spark plug caps. Spent a good part of a day tracing that down and it should have been simple, but I know now.

RandyA

[Squidley]

If you haven't done a complete tune up since you bought the bike I would suggest that. Randy is spot on with the resistor, I always change plugs, wires and caps on any 1st gen I own or work on just so I can rule those out if I have to start trouble shooting.

[mrich12000]

The way to test is one wire with a spark plug connected to the bad cyl grounded out to the cyl head try this ,

Or if your brave :pushups:and drunk to your tongue lol..

More than likely it's the wire . ***** of a job as the fairings have to come off . check the forum for coil removal links Pinwall cycle has several on Fleabay, Good luck please post pictures:photographing: especially the one with your tongue test..

Edited October 18, 2010 by mrich12000
I stand corrected by a good friend..

[Rocket]

The system has two coils.

 

Mike, there is 4 coils, as in 1 per cylinder.....

[Yammer Dan]

Take the ends of the plug wires apart and clean. Very carefully there are some small parts that will fly away if you don't watch out. Just use Flat tip screwdriver inside the wire end.

[mrich12000]

As per the correction's I received tonight, I have corrected the post.

 

Still want to see the pics of the tongue test..lol:buttkick::smash2::pushups:

Edited October 18, 2010 by mrich12000

[Venturous Randy]

As per the correction's I received tonight, I have corrected the post.

 

Still want to see the pics of the tongue test..lol:buttkick::smash2::pushups:

 

That's not fair, what did you do to correct the problem. Enquiring minds want to know.

RandyA