Legality of a home built speedo/odo

[FlyingDutchMan]

Since my speedo crapped itself (multiple times) earlier this year, I decided build my own electronic one. It works near perfectly, but I'm wondering what mr WOF or COP would think of it. It is very accurate (maximum error of +-1km/h), and the odo counts up nicely too - displayed resolution of 600mm.

I've had a look on the LTSA website and the only applicable thing that I found is that a speedo (if modified) doesn't need to be certified, and must work while the vehicle is moving forward. It does both so is it alright?

[Ixion]

Well, that's how I read the VIR-M also. I'd be prepared for an argument with Mr WoFman though

[WRT]

Well done, you gonna post pics of your handywork?

[Phenoix]

How much did it end up costing you, and is it easily done ?

Thjo to answer your question, no idea

[FlyingDutchMan]

Well done, you gonna post pics of your handywork?

When I get a digital camera... it seems to be a wee way down my "yet to buy list". I'll give a fairly accurate discription though: 20X4 backlit LCD screen trimmed with black duct taped attached to the bike with black duct tape & #8 wire. Looks better than I thought it was going to.

[FlyingDutchMan]

How much did it end up costing you, and is it easily done ?

Thjo to answer your question, no idea

Cost was very little... about $5 for a PIC16F628A (programmable microcontroller), LCD screen (freebie, but would cost about $25 from SI components), various small/cheap components. It cost me about $20 once I'd got all the nessary bits. So dirt cheap really.

Its has a fundamental flaw at to moment: It uses an infra-red LED/dector that mounted across the front disk brake counting the holes as they wizz past. Brake generate lost of dirt, and so it stops working after a while (depending on riding its 450km or 50km). Easy to clean though. Tested it with a TV remote to see how "fast" it could measure - 1453 km/h

[SPman]

I think that - as long as it works and can be seen to be working, it should be OK.
If its inaccurate - well - your call explaining to mr Plod.....

[Skytwr]

From the legal standpoint as long as you can read the display both day and night and it is accurate. The only thing is does it have a memory to retain overal milage covered. this would only be for some one buying the bike later on to know how many ks it has done.

Otherwise all good.


gareth

[Motu]

Pushbike speedos are legal,so,so long as it looks the part it should be ok...odo is not compulsory.

[Phenoix]

If its inaccurate - well - your call explaining to mr Plod.....

And that would be the problem. The princable of the speedo works easily, tho what are you using to program the chip ?

[skelstar]

Had a bit of a brain wave:
1. Buy a 200mV LED digital voltmeter from Jaycar ($30).
2. Get a voltgae/frequency converter (VFC32?)...$30.
3. Opto setup you have already that feeds the pulses into your VFC...easy LED speedo. Might have a go myself.

Admittedly it doesnt do the odo, but kinda cool anyway.

[WINJA]

Had a bit of a brain wave:
1. Buy a 200mV LED digital voltmeter from Jaycar ($30).
2. Get a voltgae/frequency converter (VFC32?)...$30.
3. Opto setup you have already that feeds the pulses into your VFC...easy LED speedo. Might have a go myself.

Admittedly it doesnt do the odo, but kinda cool anyway.

DO YOU YOU KNOW HOW FAST YOU WERE GOING SON , UMM 100MV ?

[skelstar]

DO YOU YOU KNOW HOW FAST YOU WERE GOING SON , UMM 100MV ?

Dude, thats the problem with youre stuck CAPS-LOCK is that youre going to be riding in Mega-volts and not milli-volts.
With my bike ill be riding in milli-volts for a while I think...

[FlyingDutchMan]

And that would be the problem. The princable of the speedo works easily, tho what are you using to program the chip ?

I borrowed a ICD2 (in circuit debugger 2) programmer from uni for a couple of months. I could buy one, but I couldn't justify the $160US price tag to myself. If people would like I can post up the circuitry and assembler code I designed & make it freely available. Its pretty easy to change for different wheel sizes etc. It also has a tacho read out with 50 RPM resolution and measures how long the engine has been running for and counts the number of revolutions the engine has done <-- the crowning jewel of uselss info.

My next project will be far superiour: rip out the bikes entire wiring and replace it with a CAN bus, electronic fuel injection and new electronic ignition. At the same time I'll be replacing the speedo/odo/tacho/temp/etc bits and pieces. LED lights (except head lights) and it'll look fair bling, lose some weight, and hopefully make a few more HP along the way.

[Pixie]

Cost was very little... about $5 for a PIC16F628A (programmable microcontroller), LCD screen (freebie, but would cost about $25 from SI components), various small/cheap components. It cost me about $20 once I'd got all the nessary bits. So dirt cheap really.

Its has a fundamental flaw at to moment: It uses an infra-red LED/dector that mounted across the front disk brake counting the holes as they wizz past. Brake generate lost of dirt, and so it stops working after a while (depending on riding its 450km or 50km). Easy to clean though. Tested it with a TV remote to see how "fast" it could measure - 1453 km/h

Use a reed switch and a magnet,like the cycle computers do.
You can put the magnet in the middle of one of the disc's hollow rivets.
I still prefer a cycle computer to making one myself.Far more functions available.
Cycle computers from $30 to $100