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post #1 of 5 (permalink) Old 11-15-2012, 11:14 PM Thread Starter
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Wonky Tach

Cruising on the slab the other day.
65 - 75 mph.
Cooler temps, in the low 40's (F).

I cannot help but notice the tach needle intermittently jumping 200 to 500 rpm- with me just holding steady on the throttle.

Flat road mostly, freshly repaved (nice).

A bit windy, about 15kn steady, gusting to 25kn.

Tach is electric.
I flip on my volt meter, it shows normal deviation in the 1/100's.
Nothing unusual there.

Roll on the throttle to 75 mph, tach needle climbs up like normal.
When I roll off, back down to 4K- there it goes again with the intermittent jumping.

I count seconds to see if it's a pattern. None detected.
Just every once in a while, sometimes 200, back to 4K, then a 500 jump, back to 4K.
Sometimes just 100 rpm jump.

Haven't looked to see if the connector under the seat is nicked or grounding yet.

Just wondering if anyone else may have experienced this odd behavior.
Or, if there's a short course on remedy available.
TNX in advance.
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post #2 of 5 (permalink) Old 11-15-2012, 11:41 PM Thread Starter
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Oh never mind.
Did the thing I should have before I posted-- did a friggin' SEARCH on the subject.
Even found a few with 'wonky' in the title!

Seems this is a common problem.
What's weird (in my estimation) is that a number of the complaints come from cruising at highway speeds and/or high wind situations.

Like what I was in two days ago.

I'll check leads to see they are properly seated.

I've never noticed the problem before though.
No reason to reply.
Mod can pull this thread out if they want.

Move along, nothing to see here.
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post #3 of 5 (permalink) Old 11-16-2012, 10:33 AM
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I was going to offer that it might be an intermittent ground problem but then the tach light would go out as well and the tach would go to zero.
Fairly common you say? That's interesting. And unacceptable.

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post #4 of 5 (permalink) Old 11-16-2012, 12:20 PM
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Mine did the same thing till the needle broke off whole going over a bumb
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post #5 of 5 (permalink) Old 11-16-2012, 12:43 PM
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My tach has the moves like Jagger, too. From idle to 4k, all is well. From 4k to 5k, it dances and then works fine above that.

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