I Found plans to make a Gokart Speedometer (http://www.kartingtechinfo.com/tech/mph.htm) and I was wondering if anyone has made a speedometer like this. If so hows it work and what do you think of it liek accuracy and so forth.

I was also wondering if anyone has made a simple tachomter to measure engine RMP.

Thanks Ricky

looks interesting. you might also consider the trail tech vapor computer. Has more information and optional engine temp readings. About 100 bucks for a water cooled engine, 130 for air cooled w/ temp sensor. http://trailtech.net/vapor.html