187 replies to this topic

[fixitsan]

Its amazing that I know all these words being used and it still means nothing to me!!!

 
I know how that feels.
Hoovering, dusting, washing machine. I know they're words, but I don't understand them

Edited by fixitsan, 11 March 2016 - 11:24 pm.

[Rallyist]

The 'Good Old Days' when all you needed was compression petrol and a spark and off you went with a smile on your face .

[fixitsan]

The 'Good Old Days' when all you needed was compression petrol and a spark and off you went with a smile on your face .

 

 

Yup, I agree

 

Much as I prefer simpler times and I dislike these black boxes, but we have them so need to work with them.

 

 

 

 

 

I've just ordered an 8 channel logic analyser, to map out exactly how the ignition is timed, before deciding if improvements can be made

[ProudViking]

 

 

 

 

 

 

 

 

I've just ordered an 8 channel logic analyser,

See...means nothing!

[fixitsan]

See...means nothing!

Iza box, which records the time when electrical 'events' happen.....and you can display them all on the same graph axis to see whats goin on.....

It's going to give a graph output showing exactly when the cam sensor and crank sensor triggers, and when each ignition coil is triggered.....giving either a simple graphical representation of the interdependencies of the ignition components. Or. End up looking like a game of Space Invaders.

[arthurbikemad]

BSB spec MoTec TDM anyone  

[fixitsan]

Back in the good old days, you hooked up a bulb to a couple of crocodile clips and connected those to your make-break ignition points. The bulb came on when the points opened and from that you could set static timing and dwell angle.
 
There's more 'sets of points', in the form of switches and sensors these days, but you could still hook up bulbs or LED's to each one to get a visual indication of when they're active...but your eye won't be able to see small subtle changes which take place.
 
Enter the logic analyser, which gives you an indication of when various things happen, electrically speaking, producing on-screen output such as this....
 

 
 
 
 
 
For £14 it isn't too bad
http://www.ebay.co.u...=STRK:MEBIDX:IT

Edited by fixitsan, 12 March 2016 - 12:21 pm.

[ProudViking]

Iza box, which records the time when electrical 'events' happen.....and you can display them all on the same graph axis to see whats goin on.....

 

Now this has just described a television in my mind!

[fixitsan]

Now this has just described a television in my mind!

 

 

That's close enough

[leehenty]

if the niner is giving a pulse each 36 degrees then at 8,000 rpm you have pulses in the Khz region. 1.333 khz to be exact.

Must be some ecu to keep up with it all.

[fixitsan]

Depends on the timing clock speed Lee. The processors typically run clock speeds in the order of 20MHz, slow by PC standards, but when you only need to detect a rising edge of a switched signal they hardly break into a sweat.

 

I do most prototyping with a microchip pic 18F25k22, which has an internally generated clock signal which can go up to 64MHz. The instruction cycle takes 4 timing clock cycles to complete, so it runs at 16 million instructions per second.

Edited by fixitsan, 12 March 2016 - 10:08 pm.

[JBX]

1.3KHz is very slow for a µP.

Forty years ago the 6502 was clocked at 1MHz

I still have an old 68b02 clocked at 2MHz which I used as a encrypted tv channel decoder based on line synchronization : 15,625KHz.

 

[TDMick]

When I was an apprentice I used to repair and maintain computers using discrete components transistors and diodes n stuff, with a soldering iron.

 

[fixitsan]

There's still no way of getting away from the soldering iron.....they have much finer tips these days too !

JBX i have the processor for a PDP-11 somewhere here which i fired up 15 years ago and was surprised to find the ceramic and gold monster still worked.

 

Prices for very early mcu's are going up again on the secondhand market so they're worth keeping

Edited by fixitsan, 13 March 2016 - 02:02 pm.

[Bjørge]

The 'Good Old Days' when all you needed was compression petrol and a spark and off you went with a smile on your face .

 

On my '76 XS650, I had two breakers needing adjustment at least twice per season and replacement ~every year. One day the price of the breakers was increased five-fold (~£20 each). Not very sad those days are gone - haven't used my timing lamp for ages   

[fixitsan]

Looks like I've made a mistake, and there's actually 12 trigger points on the flywheel, one per 30 degrees. (24 pulses per 4-strokes)

 

Anyhow, the analyser arrived today. I captured a good few parameters, but have saved only the ones below. The upper graph is the engine at idle.....the top trace is the crank sensor, followed by the cam sensor, then ignition coil (L) and injector (L)

 

 

 

 

The next trace is at higher speed, I twisted the throttle hard and there is a noticeable shift in the timing of the ignition coill and the injector start time, as well as injector duration. All pretty much as expected.  The left cylinder coil and injectors fire exactly 270 degrees behind the left cylinder (also as expected )

 

 

 

I've used the start of the cam sensor pulse going low as the datum. It's not meant to mean anything but it is a solid reference point from which to measure other parameters

Edited by fixitsan, 14 March 2016 - 07:50 pm.

[fixitsan]

I posted the signal traces I made above on to the Megasquirt forum to get comfirmation that they are compatible with a megasquirt/microsquirt ECU, and pleased to say that they are.

 

You can buy a programmable replacement ECU (Microsquirt) for £330 in the UK ....or £285 from the US (gambling a bit with the customs charges)

 

That seems reasonable to me for something which gives you full 16 x 16 fuel and timing maps to play with. Although, some wiring needs to be taken care of but it isn't major surgery. So If/when i get the money together I might just jump into it.

[mh1848]

i got a basic replacement for my Mk1 from Ignitech - fed up chasing old second hand models and wanted to have confidence - but they offer a programmable and race version which appears cheaper than prices above - but as am no expert may not do what you  want

http://www.ignitech....y/tcip/tcip.htm

[fixitsan]

I've seen them and the programmable versions are great on bikes with separate ignition controllers. They're not really useable on the 9er sadly, because the ECU controls everything in one box.....trying to separate only the ignition function is unlikely to work well ....BUT im only guessing based on past experience, it could be a fun experiment

[dandywarhol]

i got a basic replacement for my Mk1 from Ignitech - fed up chasing old second hand models and wanted to have confidence - but they offer a programmable and race version which appears cheaper than prices above - but as am no expert may not do what you  want

http://www.ignitech....y/tcip/tcip.htm

 

I use one on my TRX850 - excellent value and lots of usable features, especially if the fuelling/exhaust isn't stock. I'm also going to fit one onto a SZR660 I'm trying to gain a few more horsepower from