Jimmy's math problem.

[Bbqjoe]

Little Jimmy has a mini bike.
His minibike has 19" tires.
Jimmy found a speedometer for his minibike, but unfortunately the speedometer is for a 20" wheel.

To make matters worse, ebay sent Jimmy a speedometer that only registers in kilometers.

Jimmy wants to know how many actual miles per hour he is going per kilometer.
Jimmy also needs to know how many miles he's driven for every kilometer registered.

For a gold star and 20 extra points, plus a look down the teachers blouse, please answer these two questions.

It is not necessary to show your work, but a passing grade for this class will be awarded to the winner.

 

[Bwdeaton]

19/20=1/0.621

19/20*0.621= 0.59 = 59% of what the reading says will be the actual speed in Mph.

For odometer it is the same. The distance in miles is 59% of what the readout says.

---------- Post added 10-21-2016 at 12:00 AM ---------- Previous post was 10-20-2016 at 11:23 PM ----------

I guess i didn't say it above but 1 km = .621 miles so 19/20 = .95. and .95*.621=.59

 

[mckutzy]

OR.....
Dont do math... get a GPS speedo.....
I plan to get one of these gps speedo's from Speed Hut.....heheh......in KPH however.....

But I have listed a MPH version they sell aswell.... a basic model, not waterproof, very simple setup and no other bells or whistles.... but with a small motorcycle battery, you could run down the street and it'll tell you how fast your doing....

http://www.speedhut.com/gauge/GR2-GPS-08/1/GPS-Speedometer-60mph

 

[chancer]

But It sounds like "Jimmy" already spent all his money on the piece of useless crap he already has.

 

[Bbqjoe]

19/20=1/0.621

19/20*0.621= 0.59 = 59% of what the reading says will be the actual speed in Mph.

For odometer it is the same. The distance in miles is 59% of what the readout says.

---------- Post added 10-21-2016 at 12:00 AM ---------- Previous post was 10-20-2016 at 11:23 PM ----------

I guess i didn't say it above but 1 km = .621 miles so 19/20 = .95. and .95*.621=.59

Most awesome! Thanks. Here's your star.
I was gonna post an awesome downblouse, but then I remembered this is a family setting, and it would be awful if someone such as myself posted a pic of what some babies are fed with.
It isn't family friendly. Wait, or is it?

 

[Bbqjoe]

OR.....
Dont do math... get a GPS speedo.....
I plan to get one of these gps speedo's from Speed Hut.....heheh......in KPH however.....

But I have listed a MPH version they sell aswell.... a basic model, not waterproof, very simple setup and no other bells or whistles.... but with a small motorcycle battery, you could run down the street and it'll tell you how fast your doing....

http://www.speedhut.com/gauge/GR2-GPS-08/1/GPS-Speedometer-60mph

That there is slicker than deer innards on the front porch.
But not $170 slick.

 

[mckutzy]

Honestly you cant really find any other like it out there for that money........

Ive been looking for a couple of years now.....
A simple independent speedo, without need to interface with a motor itself or a computer....
Nothing for that cheap.

 

[Bbqjoe]

Honestly you cant really find any other like it out there for that money........

Ive been looking for a couple of years now.....
A simple independent speedo, without need to interface with a motor itself or a computer....
Nothing for that cheap.

If it had an odometer and a tach as well, I'd be in!
As well as being water proof.

 

[Hellion]

Found one with a HUD projector built-in, and digital. Input voltage: DC 5-12V. $30 + free S&H. Have seen them cheaper @$24 and some change...

http://www.ebay.com/itm/FREE-SHIP-2016-Digital-Universal-Car-HUD-GPS-Speedometer-Overspeed-Alarm-US-/222286442019?_trksid=p2141725.m3641.l6368

 

[Bbqjoe]

Little Jimmy's problem just got worse.
As he thought he was buying a speedometer that was mph, and went to 60, and it turned out it was in kph, this leaves Jimmy with a speedo that will only register to about 37 mph.

The bad news: Jimmy is just slightly bummed.

The good news: Jimmy is glad he only spent about $12 bucks on it.

 

[Hellion]

Little Jimmy's problem just got worse.
As he thought he was buying a speedometer that was mph, and went to 60, and it turned out it was in kph, this leaves Jimmy with a speedo that will only register to about 37 mph.

The bad news: Jimmy is just slightly bummed.

The good news: Jimmy is glad he only spent about $12 bucks on it.

You said it was only in KM/H in post #1.

Are you going faster than 37 MPH? ...

 

[Bbqjoe]

Are you going faster than 37 MPH?

More than likely... at times.

 

[Bwdeaton]

I have installed a speedometer like this on an atv once. Actually i think this is the exact one. Has programmable setting for circumference, and programmable for mph or km/h. Also has some idiot lights, but i just left those disconnected. The tach seemed pretty accurate and the speed was pretty close to what my gps said.

Link

I also plan to install one of these on my new buggy project, so I already had the link saved.