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shift counter

PostPosted: Sun Jan 25, 2009 2:57 am
by busaman
does any one know why motec will not include a simple shift counter for drag racing we have asked a few times but just get fobbed off with (you can do it with rpm/gear /whell speed) type answers. i dont think they understand the complexity of tracking wheel speed/wheelspin though 6 gears in 5 seconds.

all we need is a simple 1to 6 shift count

can anybody write/include it in the software.

Re: shift counter

PostPosted: Tue Jan 27, 2009 2:56 am
by ElectronSpeed
I personally am a bit of a road race guy but am always willing to learn . . .

What sensors do you have on the car (i.e. an ignition cut switch, gear position . . . )? In absence of those things what do you propose instead of RPM versus wheel speed? What signals or techniques would overcome the "complexity"? Are you only using this counter on your PC or are you transmitting it to a dash in real time? Do you have sample data showing the issue? . . .

Eric Schieb
Electron Speed

Re: shift counter

PostPosted: Tue Jan 27, 2009 6:08 am
by busaman
its on a drag bike 550bhp turbo hayabusa six speed gearbox i need the counter to ramp boost through the gears 1st gear is about 1.8 seconds 80ish mph then every shift is under a second, the route motec propose would be far to complicated when all we want is a simple 1-6 count.

Re: shift counter

PostPosted: Tue Jan 27, 2009 8:53 am
by IDP
I would have thought a normal gear voltage system would be simple and reliable enough.
RPM/MPH is also perfectly simple though possibly not quite as fast.
I'd imagine more room for errors when counting, what happens if the shift sensor is caught and a false upshift is counted.

Re: shift counter

PostPosted: Tue Jan 27, 2009 2:12 pm
by ElectronSpeed
Busaman:>the route motec propose

Which way are they proposing? To me the beauty of Motec is that if you have a better idea you can often implement it.

Are you referring to their drag gear detection? "For RPM based detection (Drag Racing Only) upshifts are detected on a drop in RPM."

Busaman:>all we want is a simple 1-6 count.

If by this you mean simply counting off the time, what about using the timers under general setup and feeding that into your boost control.

Eric Schieb
Electron Speed

Re: shift counter

PostPosted: Tue Jan 27, 2009 7:24 pm
by busaman
I would have thought a normal gear voltage system would be simple and reliable enough.
RPM/MPH is also perfectly simple though possibly not quite as fast.
I'd imagine more room for errors when counting, what happens if the shift sensor is caught and a false upshift is counted.

its not, there is a lot of noise and not very reliable it will move allover the place

Re: shift counter

PostPosted: Tue Jan 27, 2009 7:34 pm
by busaman
the trouble is if i use it on a table with the suzuki position sensor it will sometimes show on the log as 1-2-3-0-0-6 and on the 0 the boost drops out where as with a counter every push of the button counts as the next ramp.

Re: shift counter

PostPosted: Tue Jan 27, 2009 10:59 pm
by Brad
Detecting by rpm drop is no good at all.On Turbo streetbike applications the rpm will rise and fall in first gear as the clutch slips this will increment one count the second count will go on shift the third count can go on the wheel chirp on shifting.So we will be in 2nd gear and the gear counter could possibly be in 4th !!!
The clutch setup on a mid to low 7second 200mph terminal streetbike is critical to is performance the clutch is not always locked all the way down this serves to prevent wheelies on shifting.Therefore the rpm/speed method is both slow to lock and gives no indication of gear until the clutch locks and the speed and rpm mathmatically correlate.
I'm currently forced to run a £100 shift counter from Dyna because my multi £1000 Motec cannot count gears reliably enough!!
I'm looking nto alternative sensors which are currently pricing up at over £150 plus mecahnics either way its all addition cost where a few strokes of a keyboard and an ammendment to the software would save me and the other 20 or so UK racers that have invested in Motec money.

Re: shift counter

PostPosted: Wed Jan 28, 2009 3:35 am
by ElectronSpeed
I suspect that you have already identified the best solution: replace the existing problematic gear position sensor.

However,

Again, what are you trying to count (since we can't count speed, rpm, gearbox sensor movement . . .)?

Busaman:>push of the button counts as the next ramp.

Does this imply that you are triggering a gear change through the ECU's ignition cut? What kind of ignition cut are you using? Could you use a timer that counts when the ignition cut is active and use the timer as a boost table axis? If each shift is X amount of time . . .

Sorry, still trying to learn the issue,

Eric Schieb
Electron Speed

Re: shift counter

PostPosted: Wed Jan 28, 2009 5:01 am
by busaman
yes gearshift is acivated by the horn button to dig input 1 with 70ms kill time. every run is different due to wheelspin clutchslip human timing (its quite hard holding on to a 500hp streetbike with no wheeliebars and hit you shift at the same point every time while its wheelspinning/wheelieing or doing both at the same time)

so a simple counter is all we need i cant believe that motec cant do that.