Gotta warm up the.... TACH? WTF?

[Lucien Harpress]

So, here's a problem I've been chasing around and around since I bought the bike a year ago. Seems there's some gremlins in the tachometer (and, by extension, the whole battery charging system) that only allow it to work when they feel like.

I KNOW I've got a loose wire somewhere. I started at the (re-wired) fuse block (re-soldered THAT bit), and moved on to the connections behind the fuse block (cleaned and tightened one back there that was acting up). Well, wouldn't you know it, I still have the tach occasionally fail.

Here's what's weird about it, though- it usually only acts up when I first turn on the bike. It may not kick in for a few seconds, up to a minute or two. Then it wavers on and off for about the next five minutes (or mile or two down the road). The rest of the day? Works great.

It MAY have a tendency to work less when it's colder. But it's too sporadic to say for sure.

I'm just wondering if there's connections somewhere I haven't checked, like in the pickup coil or... wherever else that would cause it to act this way.

Anyone have ANY clue? At ALL? (Really starting to bug me, if you can't tell.)

[CatatonicBug]

This is just a stab in the dark, but since I had a similar issue, I might as well mention it. The field coil on mine broke one of the wires, just before it starts to "coil". After I took the screws out of the center of the alternator cover, it just lifted up! In this picture, point "A" and point "B" are supposed to be attached...

[cywelchjr]

It could be what cbug said, or it could be the regulator rectifier going out. If it's not starting charging completely right away it can do that. I found you can have the side that kicks the light on, or the side that the tach runs off, or everything. More likely what cbug found or another connection, although electronic parts can often start out not working and then work as they warm up.