I noticed my speedometer wasnt working after i took it as fast as i ever had. i didnt notice right when it happend i just noticed a mile maybe later.
I started playing with it taking it a apart and the cable had snapped. the cable lining was perfect, no cracks or anything. just the cable inside broke.
so is it possible that the cable was trying to bury the needle so hard that the needle bottomed out and just wouldnt let it spin anymore and the torque from the wheel just snapped it? or does the speedo just let it spin faster without stopping.
so i either need someone who knows how the speedo works, or someone to let me know that theyve gone over 60 mph with the stock speedo and still have it work after
i got a few taken apart in my room, the needle can bury no problem without snapping the cable. Why the cable snapped is because when things get old they tend to break, that cable is 7 years old, and it was never really ment to spin that fast in the first place.
"Its not what you ride, its that you ride"
1996--------Honda Elite S-
1991--------Tomos Targa-
And a Bunch of other bikes.
The mechanical speedometer has a very loose magnetic coupling to the dial needle, with the cable driving the magnet side. The needle has a low force coiled torsion spring to return it to zero. As your speed goes up, there is a fairly linear increase in torque, just enough to overcome the spring force. But the coupling is basically in slip mode at any speed past zero. It's probably just grams of force to overcome the spring. When the needle hits the stop, the magnetic coupling just continues to slip. No damage to the cable will occur from pegging the needle.
It would be interesting to find out the rpm/mph calibration of the speedometer, and how many rpm your cable is hitting at 60mph. I've got a spare Spree speedo and cable to experiment with tomorrow. I'll see about hitting 60mph... on a drill press...
Most speedos are 1000 turns per mile. So 60 mph is 1000 rpm. The speedo cable should be good for a couple thousand rpm. Going too fast is not likely to break it. Let us know what you find when you play with the speedo. I'll be surprised if it isn't 1000 turns/mile.
keithw
Honda Pal (Speed-o-scooter) JDM Spree with varator trans.
Honda Spree, 1985.
Another Honda Pal
Dac wrote:Why the cable snapped is because when things get old they tend to break, that cable is 7 years old, and it was never really ment to spin that fast in the first place.
i should have mentioned,
it was a brand new cable. Litterally put it on about 2 weeks ago.
i bought it off the seller on ebay that has tons of them.
I've broke two cables, one was pretty old so it was understandable... The second was BRAND NEW and it snapped. Little did I know you are supposed to grease the cable to prevent it from snapping. I think that's the only problem. It doesn't really matter to me anyway the scooter is rarely under 35mph, I just keep up with traffic.
keithw wrote:
> Most speedos are 1000 turns per mile. So 60 mph is 1000 rpm. The speedo cable should be good for a couple thousand rpm. Going too fast is not likely to break it. Let us know what you find when you play with the speedo. I'll be surprised if it isn't 1000 turns/mile.
keithw
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I found the drill press ran the speedometer backwards. So switched to some cordless drills. Maxed out, an old 9.6v rated at 0-700 rpm gave 15mph, a 12.6v rated 0-1400 rpm on the high speed setting gave just under 30mph for a Spree speedometer. 2800 rpm at 60mph doesn't sound too bad cable wise.
