Speedo just goes round n round

Got a seedometer with a broken needle. (Yes I will be replacing it). But in the meantime, when riding, the broken needle just spins round n round on the dial. Why? It should still function like a speedo with a broken needle, no? Did the previous owner put the wrong cable on here or some shit?

I'm in the process of rebuilding this thing. Runs solid. Working on the safety features now. Breaks, blinkers, etc. etc.....

Re: Speedo just goes round n round

Maybe the needle spring is kaput ?

Re: Speedo just goes round n round

Probably. I'm just now getting into the electrical side of things on this bike. Headlight works (although it seems someone slapped a Suzuki one on there). Horn doesn't work. No voltage from switch. Blinkers don't work (although I am getting 8 - 10 volts to the flasher when the switch is turned on). Needs breaks. Someone really beat on this thing. But....I bought it for $100 so, it's worth me sinking a little money into her. Speedo...obviously shot. Where is the spring? In the speedo housing itself? Under the needle?

Re: Speedo just goes round n round

> Mark Anderson Wrote:

> -------------------------------------------------------

>

> Speedo...obviously shot. Where is the spring? In the speedo housing

> itself? Under the needle?

Yup . You'll likely find it housed in the speedometer transmission/gear conglomerate , inside the outside housing , a little under the needle . ;)

Re: Speedo just goes round n round

spring, likely wanna just replace the whole unit, or omit it. you're goin 35 or 0 or trying to get between the 2 as quick as possible, doesn't matter much what the actual number is cuz it's not gonna get you there faster or change the top speed. they're not even particularly accurate anyway

Re: Speedo just goes round n round

I dunno. What about places like this? What you gonna do then?

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Re: Speedo just goes round n round

Well, you clearly bought a bad speedometer and need a refund, for one thing. The cable and everything else is fine, but yes, the hairspring that regulates the position of the needle is broken, and this is the result of someone opening and fooling with the speedometer without a clue as to its operation.

I suspect that a bicycle speedometer--digital and cheap; I think Walmart sells them--will do the job if you'd like a speedometer on the bike. These use a magnetic pickup near the wheel rim and you mount a magnet (included) on the wheel. I presume that you can adjust the reading to compensate for the size of the wheel; I haven't tried it.

The conventional mechanical speedometer's cable spins a little magnet near an aluminum cup that's mounted on the same pivot as the speedo's needle. Through the interaction of the spinning magnet and the aluminum cup that cup tends to be dragged along with the rotation of the magnet against the tension of the coiled hairspring, which looks like the one you'd find in a mechanical watch. I have no idea how one would replace that hairspring/needle assembly, though I'm sure it can be done.

Yes, aluminum is non-magnetic, but when you move a permanent magnet near any non-magnetic metal like aluminum or copper, an electric current is generated within the aluminum. And this current produces its own magnetic field that grabs the field of the spinning magnet.

Re: Speedo just goes round n round

LOL

Re: Speedo just goes round n round

I'm less concerned about how fast I am going and more concerned about making it street legal so I can register the thang. Pretty sure it will be required as a safety feature when my kid goes to take his road test. He is 15 and we live in NJ.

Re: Speedo just goes round n round

Get this from treatland. Had mine 2 years. 3000. Miles. No problems.i tried posting The speedo but problem. It's a 60 mph speedometer from treatland (edited)

Re: Speedo just goes round n round

> Born to be WillD Wrote:

> -------------------------------------------------------

> spring, likely wanna just replace the whole unit, or omit it. you're

> goin 35 or 0 or trying to get between the 2 as quick as possible,

> doesn't matter much what the actual number is cuz it's not gonna get you

> there faster or change the top speed. they're not even particularly

> accurate anyway

All of this is true. Which is why I use a gps speedo on my phone. It is using up to 18 satellites so it is pretty accurate. But it only really matters over 30 when most speedos top out.

I am not a big fan of the bicycle style speedos but have gotten them to work before.

Re: Speedo just goes round n round

That said, I imagine that the defective speedometer can be repaired. If the hairspring has just come loose at one end or the other it can be re-attached, and if that works then the needle can be fixed by adding a very light extension like a one-inch length of plastic coffee-stirrer to the existing stub.

Re: Speedo just goes round n round

Moped Lar (OFMC) /

No one at the NJ DMV is gonna care if the speedo is working or not when your son goes for his road test.

> Mark Anderson Wrote:

> -------------------------------------------------------

> I'm less concerned about how fast I am going and more concerned about

> making it street legal so I can register the thang. Pretty sure it will

> be required as a safety feature when my kid goes to take his road test.

> He is 15 and we live in NJ.

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