well sort of: right this is what we are trying to build. basics. 1. standard (older Two stroke) CDIs have a Capacitor that is charged by the main pickup coils (magneto), once the capacitor is fully charged then it fires... simple... the curve is dictated up the size the capacitor or capacitors and the relating input power. (o.k. not quite right but close enough) 2. the other option is a CDI with a SCR (might be wrong SRC/CSR??? but it doesn't matter) circuit. this rely on a trigger (generally a hall effect sensor) to trigger the discharge to the top coil. the hall effect sensor trigger is related to the magnetic flux of the magneto and spacings. go google it. So what we are trying to build is a mash of these two systems with a bit of smarts in the middle. step one. 12volt pickup coils with hall effect sensor. step two. cheap as chip jaycar static CDI ($28) step three: delay the trigger to the cdi using smarts (this is what we are building ~$50 parts) and a computer and some luck....
Aggghhhhh...Clear as mud.
not so clear as mud.. . . but i would be willing to to lend my bike as a test platform if you choose to do a 4t ver. .
all in all it should work of both twos and fours.... as you can set up any curve. but it is all about the trigger point (the hall effect sensor) placement i.e. you have to be able to mount it well before TDC (top dead centre) around 35-45degrees (or the most advance that you could want. the interface is running a 40 mgherts (i.e. about 200,000 RPM) cycle speed and either triggers the cdi thus spark or waits a little while and then triggers the cdi/spark. thus enabling control of the advance/retard points at any given RPM. so what we are building isn't really a programmable CDI, but rather a fancy timed relay. Where we are at with it: printed the boards and made the first circuit and (plus built the cheap ass jaycar CDI). written the base code for the microchip. (just being debuged by a geek at the moment) and nearly finished the binary complier to run in excel (as everyone can use this, in theory) this is for building up the curve and corresponding curve code for the microchip. I'm waiting to finish off my test rig (been slightly sidetracked with work).: this is a wood router (so a set RPM can be achieved) and all the standard magneto bits can mounted and spun thus the abbility to test the working rig. the idea came from the follow pages and a lot of other (so it not just my brilliant mind this time). 1. Weedeater powered raceboats: http://www.modelbouw.gompy.net/newcdi/index.htm 2. some crazy man who builds dynos in the UK http://www.sportdevices.com/ignition/ignition.htm This is also a good introduction into th workings of a cdi and a tci. the cool thing is that we don't have to do the actual CDI power function (this is what is generally problematic or $$$), which allows us to do some neat stuff in the future like: 1. knock sensor ---> retarding the timing 2. temperature sensor ----> retarding the timing 3. multiple maps and switching inrace.. 4. datalogging (OMG yes yes yes) 5. spark cuts for quickchange gear shifting or even powershifting (air solenoids etc, quite useful for sidecar racing) 6. individual gear maps to create faster reving (i.e. real extreme advance in lower gears then less for higher gears)... 7. AF ratio meters for tuning 8. and finally..... fuel injection..... o'yes this is the kicker (a $100 fuel injection kit for buckets!!!!!) as the code and the circuits are very similer.
this might have made all the work thus far a waste of time: http://www.motorbikeparts.co.nz/prod...product_id=686 o'well its good to try new things...
gutted brother. . . you know the Hows and Whats though, so your still steps above me
PM form Dave Sooo, You know how you can tune/map this CDi, did you say that you can make it "miss" for a split second? Or was that someone else talking about something else? If you can make it 'miss' (you need to teach me the lingo) then could you hook up a rev meter or just a red light, that would flash just before it was going to 'miss' (sorry) so you could short shift the gears? So you could set it up per track Say Kaitoki) with a rev range per gear so when you got to that limit, the light flashes and bam, I change gear in a flash with no clutch, passing Nigel and....yes, Dave beats Nigel on his old bike in the first points round of 2010!!! What say you? Or is that just poppy cock? ############################################### well I'll try and answer: firstly there are big gains to be made with this concept. ask glen.... What you are asking about to is an ignition cut (more common on older two strokes gp bike but becoming the fab again with fours). The very simple way is to use your kill switch as you start to apply pressure for the upshift (while holding the throttle wide open). what this does primary is to take off the engine load from the clutch therefore enabling gear change with out a clutch action or throttling off. kind of like changing gear in a old car with shit clutches (read: escorts) just hold the gear stick near the next gear and push it through when it clicks.... we move on; now-days the more common way to do it these days is to have a "secondary kill switch" (well not really but its the easiest way to describe it). connected to the gear change linkage: as you start to apply pressure for a gear change it kill the spark for the period of the upshift (this is simple to do on any system) in-fact i played around with this a while back on my ZXR using a rear break switch as a trigger (though very naughty and against the rule) mounted to my gear linkage and connected to the kill switch what I was going to do with my CDI interrupt was to build this into the micro processor (using a pickup off the gear linkage), so that the function would only run for a set period i.e. ~ ten thou of a second. then have a sightly advanced map that is triggered to deal with the extra fuel for the next 5-10 cycles (though extra fuel could be useful to cool down engine a little). As for a little red light (shift light) well go buy one and wire it in on the bench/pool room/ toolbox what ever, just not on the bike, when was the last time to looked to see if you car was redlining??? nope, you do it by feel/sound, bikes are no different. Rev counters are useful but you should be able to get away with not having one, just change when the power start to die out; you will soon get use to it. As for beating Nigel.. yea wouldn't that be good, but be warned he has got better/faster he's my target as well, in theory i should be riding in A grade (the bikes fast enough as commented by Richard), but i'm a pussy and need time back on it first. But if we put the silver bullet on a diet then there should be no reason it can't be as quick as fishies or at lease Noids....... Anyway what a novel (I'm studying so this is good procrastination)
Quote ...kind of like changing gear in a old car with shit clutches (read: escorts) just hold... WTF!! I don't know what you mean by this?! Escorts rule the world over and don't you forget it!! (well, maybe when I was 16) Quote As for a little red light (shift light) well go buy one and wire it in on the bench/pool room/ toolbox what ever, just not on the bike, when was the last time to looked to see if you car was redlining??? I don't like your tone young lady! Anyways, So if I got one of these... http://newmanz.co.nz/shop/index.php?...products_id=62 And one of these... http://newmanz.co.nz/shop/index.php?...products_id=87 and connected it to the inside of the gear linkage, where would I wire the stage one into? And what about about changing down a gear? Can it be hooked up to do that too? (with a second stage one?) or do you clutch down gears?
heeheehheee Escorts heeehhe mine use to go around IPC corner without stearing it, sack of shit..... anyway. yip get those two bits (though your really should have a deadman kill switch (the one with a string that goes around your wrist, like on the sidecar... its alittle difficult to sort out the wiring but nothing a multimeter wont sort out. As for down shifting, nope use the clutch, downshifts introduce the biggest loading and high revs on your motor (hence why i broke the studs at taupo and stacked the sidecar on higgens), the clutch can be used to control engine/wheel slipage
I understand what you are saying for changing down a gear. Makes sense. I found this ... http://newmanz.co.nz/shop/index.php?...roducts_id=179 But then read your response. This would have done the same thing wouldn't it? You could just set it on a hair trigger?....Or , what if you had a main clutch lever as normal, and a secondary shorter( in length, maybe like a decompresion lever on a 4 stroke MX bike) lever sitting directly ontop of it that had one of these set ups on it wired as you were talking before. Again, hair line set up so it was real quick and sensitive. As I write this I relise that a gear lever mounted one is heaps easier and practical. Oh well
nice out of the box thinking though, could have worked maybe ???
