Hi all, So the bike is back together after the local yobs tried to have away with it. Taking it for its first real thrashing and about half way into the ride the tach was showing 0 whilst idling (the idle sounded fine). I did notice the tach was a little irratic / looked to be showing a little higher or lower than I expected when looking down at the clocks. The battery shows about 11.6 on ignition even with oxford solariser plugged in. Charges at around 13.6-13.7 whilst running. It's a yuasa and about a year old to the best of my knowledge. The damage to the bike was snapped steering damper and smashed right air duct (which has been tapped up in temporary repair). I did have a minor issue where the crack in the air duct cover strapped the heated grip wiring stopping me from turning the bars. I just had to be a little keen with the throttle to get it unlodged and I don't think it's linked. Other than that I had been running on fumes to get to the garage but again can't imagine that's linked but who knows. Bike is a 749 2003 with black swing arm, full leo vince system, standard everything else. Any advice would be great. Thanks all
11.6v with the ignition switched on indicates a nearly flat battery. If it charges constantly on a battery tender at 13.5v but doesn't hold the charge after 12 hrs or so, then I'd call it dead and fit an new one first to see if that's the cause. If it's only charging at that rate with the engine running I would suspect a fault with either the charger or the battery. Age doesn't necessarily have a bearing on the health of a battery, rather I suspect, how it's charged/discharged regularly. I don't have an injection bike but I'm guessing that the 749 has an electronic tacho and not a cable driven one? If it's cable then I'd check the end of the cable for wear.
Great Thanks, It is injection and I would assume a reading is given from the crank position sensor but if that was faulty I would expect more issues. I'll order a new battery now and see how it gets on. The charger is brand new, doesn't mean it isn't faulty but I tested it on another battery and it did a good job.
Fair shout but sometimes it idles just fine and it does rev OK etc.. And responds just fine, doesn't look to be slipping or hanging loose.
sadly have experienced similar today on similar vintage and possibly same tacho "guts" (1000DS) so will watch thread with interest.
yes, Jamie, I didn't want to clog your thread up, as it's about yours primarily but some of the tips were: check battery condition/status and connections and confirm voltage readings (which you've done) clean and check Crank Position Sensor and gap and connector (it's worth doing this but a little bit of a red herring if bike is running the same as it was pre-tacho failure.) check all tacho signal related wiring and connectors (pretty obvious but it could flush out the culprit). There are probably some others I don't know of/haven't thought of. Finally it's a fault within instrument** and/or ECU** but probably the former. I can rule out the mechanical side of the tacho as it "tries" on first start up but then returns to zero (or less) and will still immediately respond to an engine blip but reads less than actual. It also gives a reading up to 3k randomly but actual revs are always at least double this. I am going to swap** later today to finally rule out loom, connector and ancilliary faults so can post result if you think it might help despite different bike.
Hi Chris, Really helpful thanks pal. It needs a new battery anyway so I will throw one in but I'm not expecting to find much in the crank position sensor etc.. Are you swapping out the instrument panel?. I did have to remove all the fairing and fart around the front end quite a bit so it's possibly a cable / connector. Also possible the idiots clipped a wire whilst they went at the steering damper with a chisel.
I think you have a greater chance of success than me as does coincide with your accident repair, i searched for a wiring diagram to try and trace actual tacho wire(s) journey within loom and through components but no luck so far.
There are no Tacho wires. The bike uses CanBus to transmit the tacho data to the dash. This info is created by the CPS and sent to the ECU.
I know that bit, but the instrument connects to the ECU and Crank Sensor with wires doesn't it?? that's what i meant by wires. Do you have a schematic to show a layman the tachometer circuit Chris?
Yes, two canbus wires that carry multiple sensor signals. If the speedo is reading OK then the canbus wires are OK. If the bike is running then the CPS seems to be working. There at least 16 sensors sent over the two canbus wires between the ECU and dash. If the dash is showing Speed, battery voltage, water and air temp then the canbus system is OK. There is obviously a background story with the bike and an uncertainty as to what was done to it. Does the tacho needle cycle when ignition is first switched on?
Well that is a little reassuring, I methodically checked all wires and other hardware when putting it together but I am always the first to doubt my work. The damage seems limited to the steering damper and ram air duct (in my other intro post). So I can of course be in the realms of coincidence given its the first time I have ridden the bike in anger with just enough fumes to sputter me into a garage and battery on its way out. I'll also check to see if the needle sweeps but I am sure it does. I'll put the battery in tomorrow and see how I get on.
@chrisw and @Derek are the two most likely people to help you on here that I know of Jamie, hopefully you will get to the bottom of it.
The service manual can be downloaded here https://www.dropbox.com/s/4jfimb35h3izp3u/Ducati_999_999s_999r.pdf?dl=0
