Speedometer Needle Removal

[m_stock10506]

I’m familiar with removing the instrument cluster and opening up the housing- 1984 Airhead. But, I have never removed the speedo needle. I see instructions that say just use a needle nose pliers and pull straight up. Is this right? What is holding the needle on? Anyone have a photo of this after the needle is removed?

 

[Friedle]

speedo needle removal

Mike.

I removed mine simply by twisting the throttle as far open as possible.

Friedle

 

[m_stock10506]

Mike.

I removed mine simply by twisting the throttle as far open as possible.

Mike. ��

Yeah, I managed that trick too on my ‘74, but I don’t want to rebuild the whole thing, just adjust the needle about 5 mph.

 

[toooldtocare]

I did mine when I glued the gears inside due to the odometer failure. I used a pair of small flat nosed cutters like those used to clip leads on PC boards. A pair of needle nose players would work too. Before I did it, I marked the armature inside with a felt tip pen after I moved it up about 10 mph. I held it there while I put the needle back on at the zero position. Helped the error a lot. Just pull the needle off straight. It is a slight press fit.

Wayne

 

[m_stock10506]

............... Just pull the needle off straight. It is a slight press fit.
Wayne

Thanks Wayne

 

[cwroady]

I used a couple of spoons on either side and simply pried it off on my /5.

 

[m_stock10506]

Speedo Needle Off and Adjusted

Update to this thread. I pulled the speedometer to adjust the needle position. I moved the needle off the stop and the needle moved back towards the stop. So I moved it back to the working side of the stop and again it moved to the stop. I used two small flat screwdrivers, one on each side of the needle and levered it off. Glad it hit me in the face or I don’t know where it would have landed. Replaced the needle so that it came to rest just slightly before the stop on the operational side. All back together and then a ride. The speedometer reads a little high when below 30 mph and once I’m in riding speeds of 45 - 65 mph the speedometer is now very accurate. I had a Garmin mounted on the bars right next to the cluster so I am very happy.

 

[guenner]

I tried that too until I realized the movement of the needle is not a constant angle per mph, aka non-linear. That's why the mph markers on the speedo are not at even distances. The old speedos used the magnetic field of a rotating disk to drag the needle forward - not easy to change that. All newer speedos use stepper motors and could actually be calibrated to be precise.

Now why the speedos used in BMW motorcycles typically show quite a percentage more is beyond any explanation I heard.

Even the speed displayed on my 2017 BMW is off by 3%. Better than the on my 1989 airhead with 7%.

All the cars I had which I compared with the readout of my GPS were dead-on.

/Guenther

 

[20774]

That's why the mph markers on the speedo are not at even distances.

They're even on my /7 speedo. In 5th gear I've noticed that the 5 mph is equal to 2500 RPM. Seems to be pretty consistent.

Now why the speedos used in BMW motorcycles typically show quite a percentage more is beyond any explanation I heard.

It was explained in a service bulletin. Basically, BMW wanted to CYA. There was certainly no way a speedometer would register less than the actual speed...people would be all over BMW like a cheap suit if they got tickets. Rather than shoot for the exact speed, they biased to be optimistic so that you're ground speed would be less than indicated.

 

[toooldtocare]

Update to this thread. I pulled the speedometer to adjust the needle position. I moved the needle off the stop and the needle moved back towards the stop. So I moved it back to the working side of the stop and again it moved to the stop. I used two small flat screwdrivers, one on each side of the needle and levered it off. Glad it hit me in the face or I don’t know where it would have landed. Replaced the needle so that it came to rest just slightly before the stop on the operational side. All back together and then a ride. The speedometer reads a little high when below 30 mph and once I’m in riding speeds of 45 - 65 mph the speedometer is now very accurate. I had a Garmin mounted on the bars right next to the cluster so I am very happy.

Because you are preloading the needle on the return spring it cannot be accurate from zero to whatever. You have to be moving 5 to 10 mph before it even starts moving. That said I never heard of anyone getting a ticket for speeding at 5 or 10 mph. I would much rather know a more accurate speed above 30 or so. Sounds like you accomplished that.

Wayne

 

[m_stock10506]

.....You have to be moving 5 to 10 mph before it even starts moving. That said I never heard of anyone getting a ticket for speeding at 5 or 10 mph. I would much rather know a more accurate speed above 30 or so.

Exactly. If my speedometer says I'm travelling 35 mph and I'm really going 33 mph - I don't care. When I'm going 60 mph and the GPS says 59.5 mph, I think I'm okay with that.

 

[1957mpd]

It was explained in a service bulletin. Basically, BMW wanted to CYA. There was certainly no way a speedometer would register less than the actual speed...people would be all over BMW like a cheap suit if they got tickets. Rather than shoot for the exact speed, they biased to be optimistic so that you're ground speed would be less than indicated.

I've always wondered why this was so, Kurt. In every BMW auto I've owned since maybe 2000, the speedometer has read about 3% under what the GPS nav unit displayed. Same with my '17 R1200 GSA.

 

[guenner]

I was wrong! I opened an old speedo and directly measured on the scale. The angles between the mph markers all have the same spacing and the scale is therefore truly linear.

I wonder how a speedo repair shop makes an adjustment to show a more correct speed.

/Guenther

 

[20774]

As I recall, to make changes to the actual speed with the speedometers that have the spinning disk at the end of the cable, it's about positioning the disk closer/farther away from the needle. I think there's a magnetic effect and distance controls how well the two attract to each other.

From my links:

http://home.jtan.com/~joe/speedo.htm