Speedometer Question

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thumper580
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Location: Virginia

Speedometer Question

#1 Post by thumper580 » Wed Sep 06, 2017 7:30 pm

The speedometer on my 85 RZ500 will go up to about 55-60mph and stop. The cable turns freely can't see anything out of the ordinary.. The needle just won't go any higher.

Any ideas?? Thanks.

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phildu31
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Location: Toulouse France

Re: Speedometer Question

#2 Post by phildu31 » Thu Sep 07, 2017 4:27 am

You should check the drive in the wheel

thumper580
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Location: Virginia

Re: Speedometer Question

#3 Post by thumper580 » Mon Sep 11, 2017 6:25 pm

Phil, I replaced the speedo drive and still only 60mph??? It's not that complicated of a system...

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tacky1
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Re: Speedometer Question

#4 Post by tacky1 » Mon Sep 11, 2017 7:43 pm

thumper580 wrote:Phil, I replaced the speedo drive and still only 60mph??? It's not that complicated of a system...

Try a different Gauge then, It must be that,
Did you pull the drive cable out of the speedo cable, These sometimes snap in the middle and can snag and drive the speedo a little.
1985 RZv500
1984 RZ500 Hybrid
1986 RG500 Walter Wolf
1986 RG500 Skoal Bandit
1984 RZ350
1984 RZ350 Hybrid
1981 RD350LC
1981 RD350LC Hybrid
2009 CR500AF Supermoto 250X
2007 CR500AF 250X
1988 YSR50 (2)
1989 VFR750R RC30
1984 GPZ750 Turbo

thumper580
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Location: Virginia

Re: Speedometer Question

#5 Post by thumper580 » Mon Sep 11, 2017 10:56 pm

Tacky...I'll check the cable, but I'm pretty sure it is still in one piece. Another gauge set will be a little pricey...

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tacky1
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Re: Speedometer Question

#6 Post by tacky1 » Mon Sep 11, 2017 11:13 pm

You dont need the set, just the speedo, Even to borrow a speedo, Any speedo will do as long as its mechanical, It doesn't have to be a Yamaha or for a 16" wheel. Its just to test that it goes over 60mph
1985 RZv500
1984 RZ500 Hybrid
1986 RG500 Walter Wolf
1986 RG500 Skoal Bandit
1984 RZ350
1984 RZ350 Hybrid
1981 RD350LC
1981 RD350LC Hybrid
2009 CR500AF Supermoto 250X
2007 CR500AF 250X
1988 YSR50 (2)
1989 VFR750R RC30
1984 GPZ750 Turbo

thumper580
Posts: 60
Joined: Wed Jul 12, 2017 3:34 pm
Location: Virginia

Re: Speedometer Question

#7 Post by thumper580 » Tue Sep 12, 2017 12:31 pm

tacky1 wrote:You dont need the set, just the speedo, Even to borrow a speedo, Any speedo will do as long as its mechanical, It doesn't have to be a Yamaha or for a 16" wheel. Its just to test that it goes over 60mph
Thanks again... do you happen to know if the rz/rd350 speedo will work?

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tacky1
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Location: Bay Area. CA.

Re: Speedometer Question

#8 Post by tacky1 » Tue Sep 12, 2017 8:49 pm

They will work, but im not sure if the speed will read the same, I know the FZ600 works also, But the faces and needles are different as well, The RZ has a 16 wheel with a large, high wall tire, So it might read the same as the 18" wheel on the RZ350 F2 mode.

Maybe someone can chime in on this to be accurate, I have used FZ600 clocks and RZ350 F2 clocks for parts, But I used the RZ500 innards with them..
1985 RZv500
1984 RZ500 Hybrid
1986 RG500 Walter Wolf
1986 RG500 Skoal Bandit
1984 RZ350
1984 RZ350 Hybrid
1981 RD350LC
1981 RD350LC Hybrid
2009 CR500AF Supermoto 250X
2007 CR500AF 250X
1988 YSR50 (2)
1989 VFR750R RC30
1984 GPZ750 Turbo

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2smoke
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Location: Niagara, Ontario,Canada

Re: Speedometer Question

#9 Post by 2smoke » Wed Sep 13, 2017 1:00 pm

The ratio in all those clocks are all the same. And I believe all Japanese makes use the same ratio
So they will all work.
Its the speedo drive that has to match the wheel size.
Colin

silverstrom
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Re: Speedometer Question

#10 Post by silverstrom » Wed Sep 13, 2017 3:26 pm

The RZ350/TZR250 speedo uses a different scale than the 500 speedo. If you look at where the numbers are on the face you'll see they don't line up. The higher you go, the more the offset.

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phildu31
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Re: Speedometer Question

#11 Post by phildu31 » Wed Sep 13, 2017 3:53 pm

Well, it should be just a test and try with another speedo if you have one.
Accuracy of the speed indication is not required, it's just to check if speed indication stops near 60mph ~ 100 km/h.
In 6th gear, speed is near 20-22km/h / 1000 rpm.
If speed indication goes linearly with rpm with no stop, your speedometer is out of service and you'll have to find a replacement one.
If still not, default is pretty sure in the drive mechanism.

Ron57
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Re: Speedometer Question

#12 Post by Ron57 » Wed Sep 13, 2017 7:13 pm

Hi get a drill and attach to the bottom of the speedo cable put into reverse should be to
see if it 's working properly.
Cheers Ron.

silverstrom
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Re: Speedometer Question

#13 Post by silverstrom » Thu Sep 14, 2017 12:32 am

It's difficult to get enough speed to make 60 MPH with an electric drill. 50 MPH seems to be the max I can get to here when testing. If you have a dremel tool that will run in reverse you may have more luck. I tried a pneumatic drill last week and it wasn't as good as I'd hoped.

I've found all sorts of insect life inside speedos. Try blowing some compressed air inside the cable receptacle. You can also use a few drop of WD-40, but make sure you don't get it above the dial face. I fixed a sticky RZ500 speedo that way last week.

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2smoke
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Re: Speedometer Question

#14 Post by 2smoke » Thu Sep 14, 2017 10:43 am

I believe all Japan made cable driven speedometers are calibrated to show 60 mph at 2240 revolutions of the speedo cable.
So those 2 different faces would have different calibrations inside?
Colin

silverstrom
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Re: Speedometer Question

#15 Post by silverstrom » Thu Sep 14, 2017 9:11 pm

2smoke wrote:I believe all Japan made cable driven speedometers are calibrated to show 60 mph at 2240 revolutions of the speedo cable.
So those 2 different faces would have different calibrations inside?
That is my understanding.

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