speedo exchange/electical

[DeanR]

It's raining today so I'm installing a new 140MPH speedo.
Here's both:
I hope




It looks identical to my 85MPH except for the different style connectors. I'm assuming the two black wires just splice together? Don't really want to wreck the original connector on the bike so in my electrical ignorance I'm looking for some advise on how to make this just plug right in. Without shorting anything out. Are these original type plugs available or by any chance does anyone have an extra? Thanks

[DeanR]

by the way, just click on the little pic to make it big!

[Fredjohny]

before you splice the grounds together, you should find the difference, what is inside that bubble in the harness?

[acof911]

Can't you just switch the whole wiring harness/ light bulb assy from one speedo to another? I belive that's what I did when I switched to a 140 mph speedo from an xs750.

[DeanR]

acof
yep, I have that half done but don't know how to get that center connection (with the white and black wires) apart from the case. Don't want to break it not knowing how or if it comes off! Bulbs no problem, have them out of the casing.

[acof911]

I checked my old speedo wiring harness. There is a rotation sensor in there, I think it has something to do with the self cancelling turn signals. It looks somewhat like a small glass fuse and is mounted inside of the rectangular black plastic piece. It's held in by two plastic tabs. Some careful prying and gentle inward pressure on the retaing tabs should let it come out.

Andy

[dpotter58]

I put a 140 on mine today. That piece just pops out and back in no problem

[DeanR]

That little glass thing sure looks easy to break but I got it out and back in (the old harness in the new speedo). Can anyone confirm what the heck that is and if it is related to the turn signals?
Now for a test ride.
dpotter, I thought you got the 160 MPH version?

[DeanR]

Well, it lights up nice but doesn't work. (NOS by the way).
Maybe the cable connection? Cable seemed to go on fine but might be missing something with that hookup?

[dpotter58]

Originally posted by laxdad
That little glass thing sure looks easy to break but I got it out and back in (the old harness in the new speedo). Can anyone confirm what the heck that is and if it is related to the turn signals?
Now for a test ride.
dpotter, I thought you got the 160 MPH version?

DUUUUUUUUHHHHHH you're right.....Got it up to 120 today (giggle) always wondered about that particular straight away...

[DeanR]

Speedo working well.
I now have 2mi. on my bike! Another 150 will go on today.
Thanks for the help.

[LoserShoes]

The little glass thingie is a reed relay, and yes it is an input to the canel unit. It's the bit that counts the distance to cancel turn signal.

A reed relay closes wnen a mgnet is near it.

Steve

[mro]

The little glass thingie is a reed relay

Thanks LoserShoes,
been wondering for a while about what Yamaha used for the distance part of canceling unit.

So what's used for the time element???



mro

[DeanR]

Well, I lost my self cancelling turn signal feature and don't know why. I presume it has something to do with having switched the two wire harnesses. I can live without it but would prefer it working correctly. Speedo is working fine.
Does that magnetic switch control both the time and distance elements?

[LoserShoes]

Nope, just distance, time is probably just an RC circuit in the cancel unit.

Disconnet the wires to the reed switch and put an ohmeter across them, rotate the front tire to spin the speedo, you should see the meter indcate open and short alternately. If not the switch is either bad or not install correctly. It has to be pretty close to the magnet to work.

Also if you spin the front wheel and listen closely to the speedo you might hear it going Tick,tick... each revolution.

Steve