Well that was my rant. I feel this thread has gone full circle. Maybe the AI/ chat GB news or whatever druids can help the thread starter? I'm off to calm down and watch some cute kittens on you tube shorts.
Evening all I will leave the debates on AI......above my pay grade. All i will say is that there is no such thing as bad information as long as you can filter it! Petsmith - Thanks for your post. Everything you say seems logical to me. I will bullet point my replies to stop this being too wordy! - Bike giving out the correct signal: I hope so, but I have not been able to find a definitive confirmation of what the signal coming from the ECU should look like either. Having a constant voltage and a variable frequency would make sense to me given what you have said. This is what my oscilloscope is showing. If I ever find out beyond all doubt, then I will post back here. - Put the tacho on another Bike: Absolutely, and I may give a call to arms on this if i cant create a suitable way of bench testing. Perhaps someone would be willing to receive mine via post and test, and then send back? - Disassemble ECU Connector: Done - Power Direct from battery: I'm working on this. Had some helpful guidance on how to create a tacho connector using some shrink wrap. This is part of the bench testing project but will also allow me to make a direct tacho signal feed. - Signal Generator - Absolutely. I was trying to find exactly what i needed but i think I have found a suitable one. If it turns out to be the tachos then that will mean that not only was my original tacho broken, but also the second hand one i purchased would also be duff - how unlucky would that be! Next weeks project - Bench test the Tachos. Cheers all - and apologies this has gone on and on!
I think 3 duff Tacho's suggests the problem is elsewhere. You forgot the Luigi Moto tacho that didn't work
Good point! 3 broken would be ridiculous. But for my own sanity I need to know that what I've got is working properly
Three tacho's? You spin me right round baby right round like a tacho baby right round round round! Wish you well with your quest.
Or the tacho breaking the ECU best way forward would be to fit a known working ECU AND a known working tacho....
I don't know if this has been asked before, you do have a battery of the correct size on the bike, you do start it with that and you don't have any kind of jump start kit, battery etc connected? I remember my tacho not working when I jumped the bike of a large battery. No tacho whilst that battery was connected. Disconnected- Tacho works. Connected - Tacho doesn't work. Something to do with the reg/rec. Perhaps try disconnect the reg/rec and see if it works without.
Battery was brand new in May, fitted by Luigi Moto, and is as standard. I'm not using any form of booster, I just leave it on a trickle charger overnight if I've been out interrogating the bike. The regulator/rec is still something i will consider changing once I know a) that the tacho(s) work, and b)that the ECU signal is correct. Also, regarding the ECU breaking the tacho or vice versa.....absolutely a possibility....particularly ECU cooking the Tachos. I really need to confirm beyond all doubt exactly what the signal should be that is sent from Pin 24 on the ECU.
Hello again I'm not sure if i am sorry for the slow reply or sorry to be filling up the forum again. Slow progress as I have just been absolutely battered by COVID. Had it before, nothing more than a bad cold - not this time. Absolutely grim. Id advise all to avoid it this winter. Still off work so spent some time pottering. Anyway - I have now bench tested the tachos. In simple terms, they work. No if's, no buts, 12v signal at 36Hz is around 1000rpm, and various other frequencies checked. They work exactly as the specs say they should (see pics). I've spent some time rechecking everything. All my conclusions to date are this: - The Tacho works when given a 12v, square wave signal - The ECU is giving out a square wave, 12v signal - The signal at the tacho connector is square wave, 12v and identical to the ECU. - When the tacho is given the signal from a signal generator it works, when getting the signal from the bike it does not. I just don't get it. I set the signal generator to a signal that was as close as I could possibly get to the bike at idle. No problem. Pics attached so you can see what i've been doing. Ignore the RPM on the clock - i was messing with the frequency to make sure it worked at various RPMS. The pic of the signal generator and Oscilloscope are related. Anyone with any ideas? I'm considering if it could be as simple as the white tacho connector on the loom not making good contact. Any idea where i could get a replacement? that little bit of loom is £50 - seems a lot to replace a connector!
Humour me, try running a jumper lead from the battery negative to a bolt on the engine. To see if it is an earthing issue. At the moment you are the resident Tacho Expert.
Sorry to hear you've been ill. incredible, it has to be staring "us" in the face now, baffled at the moment. A bit of lateral thinking needed now. When you say "The ECU is giving out a square waveform 12v" - is the source for this at the connector when unattached to the tacho?
It's driving me mad! Yes, the 12v square form is at the connector when unattached. I also get the exact same signal direct from PIN 24 at the ECU. ........And I created that exact signal with the signal generator......which made the tacho work. I've also just tried lashing in an additional earth from battery to engine. You've guessed it, still no action. I feel exactly as you say......it's me that can't find it rather than it being something utterly impossible.
my memory isn't what it was, but I think we can say that it has to be one of the other two leads logically doesn't it? The Earth is a good call, because it's something to do with the stability of receiving the signal now, you have proved that the trigger/signal is there?
