what do you need measured

[aff-man]

Right project time guys. Now i don't know exactley how this project is gonna work but here is my idea. I wish to build an onboard system that monitors a bike while racing. i.e. lap times top speed ect. But in order to put this idea forward to my lecturers i am gonna need to have a design brief sorta worked out. So here is the hum dinger, i need to know what to measure. I have lap times and top speed, but what else is there????? any idea's welcome maybe i can find out how to make cheap ones for all the budding racers out there.

[Two Smoker]

Definately average speed, as well as top speed and lap time.... hmmmm dont think i would need much else, oh storage of lap times would be good, and a number next to the time representing the lap.....

Count me in for one

[merv]

The GP guys measure just about everything don't they - speed at all times and then the actual bike operational stuff like gear your in, braking, temperatures and all that stuff - so really take your pick how far you think you can go.

[dangerous]

How about the amount of time that the frount wheel is off the ground and for how far

[wkid_one]

Shit you could go absolutely mad.....when braking applied, brake force, suspension load, engine revs, temp, gears, front v rear brake useage, throttle application, oil pressure, fuel consumption, max top speed, av speed, tyre temp, tyre pressure, weight distribution etc etc etd

[Two Smoker]

Shit you could go absolutely mad.....when braking applied, brake force, suspension load, engine revs, temp, gears, front v rear brake useage, throttle application, oil pressure, fuel consumption, max top speed, av speed, tyre temp, tyre pressure, weight distribution etc etc etd

Whilst he could do that, i think for cost and simplicity the ones i stated would be good..... Ofcourse i would love to know section times and braking points etc.... but $$$$

[scroter]

try performance bikes magazine[uk] they often datalog there bikes for all sorts of things,dont tell you how its done but!!!

[Ghost Lemur]

It all depends on how indepth you want to get. As dangerous said the GP guys measure everything realtime. So you can see speeds throughout the circuit, temps, pressures, rev count, etc.

The more indepth it is the more useful it will be, but on the downside the more work you'll have to do.

[Kickaha]

My priority for a basic system would be a dual display

1 Lap time
2 store lap times so you can recal and scroll through
3 display what lap is fastest time
4 Average speed
5 split times,using more than one beacon
6 Temp,with max temp recall
7 max speed,it's a bit of a wank,but good for seeing if your speed onto the straight is getting better(lap time is far more important)

check here to see what other systems offer
http://www.aim-sportline.com/
http://www.piresearch.com/

[geoffm]

Right project time guys. Now i don't know exactley how this project is gonna work but here is my idea. I wish to build an onboard system that monitors a bike while racing. i.e. lap times top speed ect. But in order to put this idea forward to my lecturers i am gonna need to have a design brief sorta worked out. So here is the hum dinger, i need to know what to measure. I have lap times and top speed, but what else is there????? any idea's welcome maybe i can find out how to make cheap ones for all the budding racers out there.

My Datamite (www.performancetrends.com) will pretty much measure whatever you want, depending on the sensors and the volume of cubic dollars you want to put into it. Generally, engine rpm, rear wheel rpm, front wheel rpm, distance (from those), temperatures, fork and shock travel with a linear potentiometer, etc.
Laptimes via Hotlap or similar IR sender and reciever unit.
Download the software (demo) from their site for ideas
Get a book called "data power - racecar data aquisition" - has a lot of this stuff.
There used to be a data aquisition mailing list, but it seems to have fizzed.
Check the gokart guys - they do a lot of this stuff.
Geoff

[geoffm]

You also want to measure speed at all points around the track and overlay laps. Lets you know if you really are going faster or not, and where.

You may also want to hook up exhaust gas temperature probes (k type thermocouples) for jetting, although this is usually done on with live readouts.
Geoff

[aff-man]

Cheers guys that's heaps of info. The unit i was thinking of making would be a plug in system that you plug in the bike and measures stuff i.e. lap times(from various sensors to get times at different possitions), top speed and i'll probably add engine temp, gearing and some other fancy stuff. And then gonna write a comp program that basically you detach the unit from the bike and via a serial link you can download data and plot graphs ect of stuff. Just an idea but i think a cheapish device could be benificial as well as interesting to work on. Now i just gotta convince the lecturers oh well wish me luck.

[Hoon]

Yeah I briefly entertained the idea of designing a bike data logger. I originally tried a microcontroller but it ran out of memory. I now reckon using something like an ipaq to drive the sensors and using its built in wireless to connect back to the pits is the way to go. You could even mount a webcam!

But yeah the stuff I'm interested in is:

engine rpm
rear wheel rpm
front wheel rpm
front suspension travel
rear suspension travel
throttle position
front brake
rear brake
handle bar position
temperature
o2 sensor

Also some sort of mapping would be cool too!

Hey geoffm, that datamite is seriously impressive looking! Do you get all the sensors with it too?

[geoffm]

Hey geoffm, that datamite is seriously impressive looking! Do you get all the sensors with it too?

I got the 4 channel Datamite 1 - the 32 channel Datamite 2 would have been nice, but an overkill for what I want.
I upgraded to the 512K memory when I got it, which should give 20-30 mins of data recording, depending on the sampling rate
I got the standard kit-o-bits, which includes a rotation sensor (a hall effect sensor and magnet) for my dyno drum or wheel, and it comes with a wrap a wire around the lead inductive rpm pickup. I also got the clamp on inductive pickup (as it is easier on the dyno) and optical isolator for the computer, so I can see real time RPM readouts.
Most of the other sensors should be pretty straightfoward if you have a solid electronics background. The manual covers it pretty well and is worth a read.
I did get a spare loom for on the bike, but haven't actually used it yet - no time, no money and no working bikes...
Geoff

[geoffm]

Cheers guys that's heaps of info. The unit i was thinking of making would be a plug in system that you plug in the bike and measures stuff i.e. lap times(from various sensors to get times at different possitions), top speed and i'll probably add engine temp, gearing and some other fancy stuff. And then gonna write a comp program that basically you detach the unit from the bike and via a serial link you can download data and plot graphs etc of stuff. Just an idea but i think a cheapish device could be benificial as well as interesting to work on. Now i just gotta convince the lecturers oh well wish me luck.

Go for it if you can get it to go. Have a look at the Datamite software for ideas. Do a version for running the bike on a dyno as well, and I will help you test it out.
Have a look at using a BasicStamp - a guy in Aussie (just out of Melbourne) has used one for his dyno, however I don't know what the limitations are for storage. Easy to program.
Most cheap aquisition systems are made to read directly into the PC and so only have a small storage buffer.
My Datamite has 512k, and they say it is good for 20-30mins, depending on the channels used and sampling rate.
Geoff