RD350YPVS Tacho same as 500?

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SimonLC
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RD350YPVS Tacho same as 500?

#1 Post by SimonLC » Sun Dec 20, 2020 6:47 pm

Anybody know if the 350 YPVS tacho is the same? Looks the same and 3 wire connections on the back. I am guessing yes?

MK
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Re: RD350YPVS Tacho same as 500?

#2 Post by MK » Mon Dec 21, 2020 11:45 am

Yes it fits mechanically and electrically.
TZR 250 2MA/1KT would do, too.
Only issue is different redline on the rpm scale.
Bye
Martin

silverstrom
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Re: RD350YPVS Tacho same as 500?

#3 Post by silverstrom » Mon Dec 21, 2020 3:48 pm

MK wrote: Mon Dec 21, 2020 11:45 am Yes it fits mechanically and electrically.
TZR 250 2MA/1KT would do, too.
Only issue is different redline on the rpm scale.
Redline is 10,000 for RD500, RD350 YPVS (1985 F1/N1 and onward) and first generation TZR250. The tachometers are identical. I have them all here and have been servicing them for years.

MK
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Re: RD350YPVS Tacho same as 500?

#4 Post by MK » Mon Dec 21, 2020 5:48 pm

Wasn't sure about the 250.
Even better if it's identical, so there's more choices.
Bye
Martin

SimonLC
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Re: RD350YPVS Tacho same as 500?

#5 Post by SimonLC » Mon Dec 21, 2020 8:31 pm

Have you had trouble removing needs from them ? I’ve broken 2 now pulling needle off and it pulls the shaft as well.

silverstrom
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Re: RD350YPVS Tacho same as 500?

#6 Post by silverstrom » Mon Dec 21, 2020 11:11 pm

To get the needle off use 2 small spoons. Put one on each side and use them as levers. Just push down on the handles. If the needle is really stuck on it may not come off without considerable force and the risk of damage.

Why are you removing the needle? It typically isn't needed unless you are replacing the dial face.

SimonLC
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Re: RD350YPVS Tacho same as 500?

#7 Post by SimonLC » Tue Dec 22, 2020 5:25 am

Yes it’s the spoons I’ve been using. I been trying to change the clock faces . I have kph speedo which I’ve managed to change no problem but tacho wont come off and needs to be changed to match.

MK
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Re: RD350YPVS Tacho same as 500?

#8 Post by MK » Tue Dec 22, 2020 2:19 pm

I'm holding the axle with pliers that I ground pretty flat.
Loosening the screws that hold the clock plates helps a bit to get the pliers into position.
The reason is that I pulled out the complete needle/axle assy from the rotating coil on my first try which made the instrument disfunctional...


Plus using two small screwdrivers to pop off the needle.
(if you counted right, you need three hands, i.e. ask someone to help)
Bye
Martin

SimonLC
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Re: RD350YPVS Tacho same as 500?

#9 Post by SimonLC » Tue Dec 22, 2020 2:27 pm

That makes sense 👍. Thanks for advise

MK
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Re: RD350YPVS Tacho same as 500?

#10 Post by MK » Tue Dec 22, 2020 2:48 pm

More important advice:
Bend the needle over the stopper and mark the equilibrium position BEFORE popping anything off...

The coating on the plate is sensitive to fingerprints. Do not touch!
And if you did, DO NOT clean with alcohol. That dissolves the paint.
Bye
Martin

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