Speed Of Your Karts

[Russ2251]

Speed calculator can be used to ballpark speed.
http://www.diygokarts.com/speed-calculator.html
Using a TinyTach also works.
http://www.tinytach.com/tinytach/commercial.php
Or a GPS can be used.

 

[jr dragster T]

Russ do you think the TinyTach that updates every 2 seconds would be alright for my kart? I wasnt sure because there's a fine line where overrevving is and it wont take long to get there.

 

[Russ2251]

Get the more expensive one. Updates every 1/2 second.
2 seconds is a long time when monitoring rpm, especially when dealing with anything modified.
The extra $30 is well worth it. My opinion.
I was considering buying a 2nd unit, but I may just wire up both engines and monitor each through independent switching.

 

[jr dragster T]

Ok thank's Russ. That's what I was thinking that in 2 seconds it could go from safe to not safe and not realize it.

 

[Kenny_McCormic]

A $10 digital bike speedo makes a GREAT 10K rpm tach.

 

[ZnsaneRyder]

A $10 digital bike speedo makes a GREAT 10K rpm tach.

Plz explain how this is done

 

[Kenny_McCormic]

http://www.instructables.com/id/Tachometer-made-from-a-bicycle-speedometer-cycloc/

 

[ZnsaneRyder]

http://www.instructables.com/id/Tachometer-made-from-a-bicycle-speedometer-cycloc/

THANKS!!! I wonder though, if the magnet going by so fast would affect the accuracy of the magnetic hall-sensor to pick up the RPM.

I also wonder if that magnet would cause a balance problem at high RPM, or even fly off!

What if we used the yellow ignition wire for the kill switch to also get the RPM signal from, and used a transistor to trigger the bike computer instead of the hall-sensor?

 

[Kenny_McCormic]

Use that big magnet already conveniently located on the flywheel. Gut the big box for the sensor and it will probably fit inside the shroud away from the coil without any cutting. Electricity and magnetism is faster than any engine, I wouldn't worry too much.

 

[trails]

i want to install one just as a speedometer.

 

[BradenM]

Measure in MM the distance it takes for one of your wheels to make a full revolution, and key that number into a cyclometer. Then attach the magnet to the wheel you measured (going to have to be some ghetto homebuild here, sorry), and attach the sensor so it is no further then 1/2 inch away, although preferably within 1-2mm. Attach the bike computer to your preference, and make sure you secure the wire from the sensor to the screen.
Braden.

 

[tallboy2828]

196cc Honda Clone, direct flow to the air filter (no restrictive airbox cover) and no governor.

Hilliard Extreme Duty clutch, with 1800RPM springs

3:1 axle ratio (belt drive) and 10" Marathon Flat-Free solid poly tires. Gives me a good 50MPH. Max I've ever clocked, ducking my head close to the handlebars to reduce wind resistance with tight clothing on (according to bike speedometer) is 51.6MPH.
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Dual Suspension Mountain Bicycle with a big engine on a trailer! 196cc OHV Blue Honda Clone, 100MPG, 50MPH, No RPM limiter 5000+RPM

you mean 18 pound springs, stock springs will do 3600 rpm.