Speedo acting up

[trex]

03 FXD. 52000 miles. Is there any way to test if a irregular speedo is the fault of the sensor, calibrator or the speedo itself? I had to put in a S&S calibrator a couple years ago because of Andrews gears making it read wrong. The first one went bad and was replaced and has been accurate since. I looked at the sensor and it had a little graphite looking film on it so I cleaned it off. What it is doing is after a few days of not riding it'll stick at a low speed or zero until I goose it up to 70 or so then it pops on and is good after that. I live in the tropics so salt in the breather hole on the speedo, I'm thinking maybe could be causing it. Also I have had a small flying insect inside the glass for years now, dead of course. So if he could get in dust or salt could too. So back to the original question, any way to teat what is causing it?

[FSG]

This is what I did when the Speedo went walkabout.

http://www.harleytechtalk.com/htt/index.php?topic=95816.0

[trex]

Thanks FSG, I'm no good at electrics so the testing went over my head, I'll just replace the sensor and go from there. Sounds like that is most likely

[trex]

This is what I did when the Speedo went walkabout.

http://www.harleytechtalk.com/htt/index.php?topic=95816.0

I haven't got a sensor yet, they have to order it. So it looks like the way to do it on my Dyna is to take out the battery to get better access, dismantle the connector on the new sensor, cut the wire at the old sensor next to the part that bolts to the tranny, tape the new disconnected wire ends to the old wire and pull it up through the frame route, reconnect the new connector parts and call it macaroni. That it FSG?