My speedometer isn't keeping up accurately. Fuel gauge is not working

[Shocker]

My speedometer is working but not accurate so much. It's about 5mph slow around 40mph. 60-65 might be something around 50mph on the gauge. Found new speedometer cables on eBay and was curious as to whether this is the quick fix for my problem.

What are my options to remedy the non working fuel gauge?

[oldyam80sg]

Fuel gauge-Is the wiring going to the gauge connected? Do you see a red light in the housing showing its on? My 80 SG has a red fuel light and if I'm low the light illuminates red. The tank has a metal plate the wires go to. Look to see and get back to us.

[cajun31]

My speedometer is working but not accurate so much. It's about 5mph slow around 40mph. 60-65 might be something around 50mph on the gauge. Found new speedometer cables on eBay and was curious as to whether this is the quick fix for my problem.

What are my options to remedy the non working fuel gauge?

Identify your bike. Do you have a special or a standard. What year.

[jetmechmarty]

My speedometer is working but not accurate so much. It's about 5mph slow around 40mph. 60-65 might be something around 50mph on the gauge. Found new speedometer cables on eBay and was curious as to whether this is the quick fix for my problem.

What are my options to remedy the non working fuel gauge?

First, what is the size of your front tire.

[Radioguylogs]

I don't believe a new cable will solve your speedometer problem.

The cable is turned by a gear that is driven by the front wheel.

Since the cable driven by a gear, it can't lose RPM unless the gear is stripped.

Seems the problem is (a) modified wheel/tire size (Jetmechmarty) or (b) the speedometer itself.

I have an XS750 speedometer with old stiff grease and wouldn't keep up with the actual speed. It recovered with some lubrication and exercise.

[bikerphil]

What are my options to remedy the non working fuel gauge?

I would start by reading page 6-15 of the FSM, it gives a step by step troubleshooting sequence for fuel gauge malfunction.

I read your profile and it looks like you have a 79 Standard.

[bikerphil]

duplicate post

[Shocker]

First, what is the size of your front tire.

Front tire size is 100/90 -19

I have a 79 1100 F Standard

I appreciate the help guys. You've given me a good place to start.

Coincidentally the Clymer Service Manual I found on eBay arrived yesterday evening

[jetmechmarty]

Front tire size is 100/90 -19

I have a 79 1100 F Standard

I think your issue is going to be the clock itself. Examine both ends of the cable for evidence of slipping or not square to rule out the drive and cable. An oversize tire is ruled out.

[DiverRay]

On a couple of the Standards I've owned, I needed to free up the grease in the speedo. I had one that snapped a new cable, it was so bad. I used a little WD40 to clean, a small squirt with the gauge upside down, wait about 10 seconds and flip over to drain. Repeat about two more times, then use a good silicone lube spray and leave it upside down for about two minutes. Worked for me.

[LenB]

Also had a dead fuel gauge on my 80G and after all the test procedures (as per bikerphil's post) narrowed it down to the regulator (2H7-85755-00-00). Seen some posts regarding making one of these based on what it's supposed to do, but I'm no electronics wiz and didn't want to risk my tach bursting into flames in front of me while driving down the highway. It's a part no longer that easy to find but my fuel gauge works like new . (PS - that's a cooked one in the picture -
bought a used, untested unit the first time and got my money back)

[bikerphil]

Yep Len, the regulator is usually the culprit. I have 6 or 7 bad ones here, some read 10 volts, the others zero.

Shocker, if the regulator is your problem, I can make you one for about $2. With inflation it may be closer to 3.

[Radioguylogs]

On a couple of the Standards I've owned, I needed to free up the grease in the speedo. I had one that snapped a new cable, it was so bad. I used a little WD40 to clean, a small squirt with the gauge upside down, wait about 10 seconds and flip over to drain. Repeat about two more times, then use a good silicone lube spray and leave it upside down for about two minutes. Worked for me.

This is likely necessary, but careful not get oil on the inside surface of the glass.

[LAB3]

I've seen WD-40 wash the black right off the speedo face. After that happened I've always sprayed it in with the face pointing upwards so it couldn't work it's way down there

[bikerphil]

Here's a pic of the tach harness with the new regulator installed. It's not plug and play, it needs to be soldered in.

The new regulator is the small one on top, the old one cut off and directly below.