wonky Tachometer

[RedMenace]

Coming back today my tach had a wonky momemt. Was the end of a long ride, much of it over rough ground. Had just gotten back to pavement was cruising at about 3 grand over level road when the tach became erratic, droped to zero spiked to top wavered in between, momentarily behaving with a proper read, then repeated. I shifted and it went normal for the remainder(1/4 mile or so) of the ride.

Any ideas what was going on? THe bike did not miss a beat, no bad sounds no flicker of the dash lights(as far as I could tell).

[RedMenace]

Another data point: Started up just fine this morning-hadn't gone far when the tach started acting up. This time the engine was definately misfiring, tho I couldn't tell if it was missing or firing out of time-intermittent, but no doubt it was there.

Where do I look first?

[NortonCharlie]

ignition pick coil comes to mind.  It generates the output that fires the coils and run the tach.  It could be anything in the circuit like a faulty wire, but it seems like there have been quite a few pickup coil failures on steamers.

[RedMenace]

I would really like to go to the sidecar rally in Yakima this weekend. The Triumph shop is an hour and a half away and I doubt if I can get off work in time to get there. I was tempted to try anyway and have them use the official Triumph ignition tester on my bike but I called the shop and was told, yes, they have the tester, but it "isn't worth the powder to blow it up".

So I went ahead and ordered the igniter(pickup, crankshaft position sensor?I hope these are all the same thing with different names?). It should get here Friday. In the meantime I went up the street to Joel's and borrowed a coil and the brain from his 96 Tiger, figuring I could swap out bits one at a time and see if one of my coils or the black box is bad. The thing is, now the bike runs perfectly, the tach is behaivng itself, there is no problem to diagnos! I rode it around a bit and got it good and hot with nary a stumble.

What I have done so far: pull the plugs and check for spark-looked good. Pulled #2  coils, unplugged hig and low tension leads and inspected- looked fine. I did buff a little green off #2 HT lead at the base, but it had good contact prior to doing that; checked my compression just for laughs-it was fine, I giggled and put everything back the way it was. Didn't even clean or gap the plugs. Located but did not unplug the connector in front of the battery that comes from the ignitor. Externally it looks fine. Left the sidepanel off, put the gas tank off and fired her up. Runs perfectly. I don't know if disturbing the wires on the coils fixed it. I doubt it-think it is just so damned intermittant that the problem is hiding.

Going to ride it to work and see if it behaves today.

[NortonCharlie]

I can't count the number of times I have permanantly fixed something by taking it apart, looking at it, finding nothing visibly wrong, and putting it back together.  I have learned to use di-electric grease on most connectors.



At least you will have the part on hand when/if it fails.  



Good luck

[RedMenace]

took the bike to the Yakima sidecar rally, did as much dirt as I could find between here and there. Was in the saddle from 1030am to 530 pm with a short break for lunch at the Bluebird saloon in Bickleton on the way home yesterday. Bike ran like a top. Sustained highway speeds of 70mph+, saw 85mph on one gravel stretch. Did a lot of very technical very rough stuff on the way home 3mph-40mph, first to third. Some deep water crossings, put the axles under a couple of times, one stretch of road was submerged for about 75 yards. Only failures were the weld mounts on the sidecar fender snapped off and I ruined another Washington State Gazateer by soaking it in a mud slurry. Guess the ignition fault is fixed(probably;-)

[Tigermoto]

Had wonky tach, speedo, and gauges this spring.  Tach was first to show trouble.  I was running electric jacket, gloves, socks, heated grips, and PIAA road lights @ 27 degrees F.  Once I turned off the PIAA's, the gauges all normalized.  I added a black Kuryakin voltmeter to help assess electrical status and switched from 55W to 35W bulbs in the PIAA's.  Running like a top now.