Shake the Box CL360/378 - The Hedgehog - Done

And therein lies the rub. We love our cheap Chinese electronics and they are often amazing, but at the lower end of the price range we take more of a gamble on accuracy and dependability and with little or no customer support.

Your kiln anecdote reminds me of the sexy electronic copy of an older TZ analgue temperature gauge. It's probably accurate and it sure looks nice but the rate at which it registers change in temperature is so slow that in a motor with a problem, it would tell me it's getting hot some time after it melts down.

Response time is important.
 
I suspect his speedo is wrong because the circumference which was input was not the actual measured circumference, but a calculated value.
 
Wow, I go out for an afternoon and this thread gets more posts than it usually gets in a month. Interesting. First, I'm not sure that the speedo is off, I suspect that it is based on it seeming to be reading slow. That's why I'm going to go out w/ GPS going and see what it shows. It could well be that the combination of not being on it for a long time and the noise it was making had me thinking I should be batting along faster than 55 and 60 mph. I won't get to it today probably, but hopefully tomorrow the GPS and I will see what's what.

I think this technical stuff is getting beyond my pay grade as I'm only an old retired military office manager, former paralegal and executive assistant, but I'm still very sure that it's all pretty simple. Pass a magnet by a Hall sensor and create a pulse. One magnet on the rotor causes one pulse per revolution. Feed that pulse into the little computer thingie and it decides that one pulse is equal to XXXXmm. (XXXXmm in this case being what I tell it to be having the choice between anything from 0001 to 9999.) The little brain then takes that XXXXmm info and uses the number of pulses per minute (probably uses an increment much smaller than a full minute) and calculates it to = a certain speed and distance traveled.
 
ex119x said:
I suspect his speedo is wrong because the circumference which was input was not the actual measured circumference, but a calculated value.
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Will be taking care of that. To an extent it was measured because the actual diameter of the tire was measured and then I calculated that diameter into a circumfrence and then converted inches to metric. There'll be a little loss (or gain) in all of that, but getting an actual circumfrence should clear up most of it, though there could still be a few decimal points difference in the conversion from inches to metric. Spose I COULD do the initial circumfrence measurement in metric... if I can find a meter stick around here. :)
 
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These things are like oem they are made to read slow. If you put exact perfect mm size. 5 mph or more low is normal. Irks method to start at suggested the adjust size until.it matchs gps is only way you'll get it right. My honda car reads 7 mph slower than gps. I put larger tires on and now it reads 2 mph faster than gps. Not sure what it uses for a sensor but bigger diameter chaged the speed reading.
 
OK, yeah. IF it's set up to read slow, either by design or just questionable design/quality then, yes there would be a certain fudge factor to go for that should correct things. I'm guilty of assuming that if I put in the correct circumfrence I'll get the correct speed. That being said, as stated below...

3DogNate said:
New Speedo Pulse = (Original Speedo Pulse x Indicated Speed)/Acutal GPS Speed

Pretty sure that's your formula for nailing your speedo pulse rate.
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...makes perfect sense to me. I stand corrected and thank you very much!

I just checked and the correct circumference is 75" rather than 77" which is 1905mm.

So, using hypothetical numbers, indicated 55, actual 62: (1905 X 55)/62 = 1689.91 If that were the case I'd set the circumference to 1690 then the readout should be pretty close?
 
Yes and then do it again with the new readings and you should be able eliminate that decimal error completely if it’s not 100% agreeing with GPS already. (It’s probably going to agree)
 
And the other wrinkle, as I think of it, is that I've got the thing set to 1956 and it seemed like it was reading slow. I'm going to change the setting to 1905 it's going to read even slower. We'll see what happens.

I guess if I really wanted to be adventurous I could set it to 9999 and then old RideSolo could pretend he's Han Solo putting it into Hyper Drive. Wouldn't feel any different but maybe the super indicated numbers would bring on delusions of grandeur! "Punch it, Chewie!"
 
That's the problem. Marty travelled to 1955, not 1956, and even then he still ended up in a kerfuffle with Biff that almost screwed 1985.
 
Have you got a Flux Capacitor that I can borrow? Now that the thing is a 378 it might actually get my lard ass up to 88mph!
 
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ridesolo said:
And the other wrinkle, as I think of it, is that I've got the thing set to 1956 and it seemed like it was reading slow. I'm going to change the setting to 1905 it's going to read even slower. We'll see what happens.

I guess if I really wanted to be adventurous I could set it to 9999 and then old RideSolo could pretend he's Han Solo putting it into Hyper Drive. Wouldn't feel any different but maybe the super indicated numbers would bring on delusions of grandeur! "Punch it, Chewie!"
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1956 will read slower than 1905. 1905 is fewer pulses to reach a mile (faster) than 1956 pulses.

Oh, and Dark Helmet prefers Ludicrous Speed.
giphy.gif
 
3DogNate said:
1956 will read slower than 1905. 1905 is fewer pulses to reach a mile (faster) than 1956 pulses.

Oh, and Dark Helmet prefers Ludicrous Speed.
giphy.gif
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Yeah but each pulse is a distance. At 1905 each rotation is 51mm shorter than if it's set to 1956. So while you may be making pulses faster, each pulse will be a shorter distance.
 
ridesolo said:
Yeah but each pulse is a distance. At 1905 each rotation is 51mm shorter than if it's set to 1956. So while you may be making pulses faster, each pulse will be a shorter distance.
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You aren't measuring distance, you are measuring time (frequency). Bigger tire = fewer pulses per given distance (Lower Frequency). Smaller tire = more pulses per given distance (Higher Frequency)
 
Take your 8 magnet apparatus and use it with the speedo set to 100mm. That ought to get your 15,835 miles awful quick. 9999 is too high. You’re thinking about it wrong.
 
Who really cares. Set it up, ride with a gps, adjust the setting rinse repeat until accurate enough. Done. Ride.
 
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