Ah i see, i missed that. Why do they ever put these regs in stupid places with no airflow in the first place?!
There’s a guy up at Dunkeswell airfield on the industrial estate there and there’s SP motorcycles in Exeter but I don’t know of anyone near Bideford - Devon’s a big county. Sorry I can’t be more helpful.
Does it need to be a Ducati specialist? There may well be a competent mechanic or auto-electrician in the Bideford area that could do a fine job. If it needs to be someone familiar with Ducatis, there is another place near the station in Exeter where the guy has a shim kit, so would fit that bill and is probably rather cheaper than SP Motorcycles I can look up the name... However, is this not a rather hasty diagnosis? It could well be a good idea to replace and relocate the reg/rec anyway but I can't help thinking the problem may well still be there afterwards.
Yes it would be sensible to do some voltage checks before going too far, charge the battery, get the bike started and check across the battery terminals for charge rate would be a good start. Steve
Hi Coldrobba (sorry missed this last night and away tonight) I am planning to check all the cables and fuses at the weekend so will report back on burnt wires after - at the moment I can’t be sure. Brief resume: I had put 10 litres of 97 octane fuel in it but it wasn’t empty so have discounted that on the basis that the new fuel would have mixed with the old(er) fuel which had put in a week or so back. I also ran with the headlights on yesterday which I hadn’t prior and wondered if that hadn’t helped? Battery is new (15th October) and on an optimiser. Started perfectly yesterday and run well until I’d been in this slow traffic for about 4 miles (lights, queuing, etc.). Started to misfire which got worse and eventually stalled with battery dead flat. As I say, battery did recover enough for me to restart it approx. half an hour or so later and run OK for about 100 yards before it misfired and stalled again. Suggested the regulator as seen loads of posts about it “frying” and getting too hot due its position but would be good if it was something else Thanks to all for your help and advice! PS also have a 1972 900SS which has never given me any trouble (yet).
If the battery is fully charged when you set off but the bike is not charging as you ride, with the lights on it would probably travel around 15/20 miles before it started to misfire, up to 40/50 miles without the lights switched on. When my first reg/rec failed i had this happen, from setting off i stopped and restarted the engine twice travelled about twelve miles with lights on and the bike started missing and getting worse quickly,switched the lights off and it helped for another 3/4 miles until it was misfiring so bad I daren't go any further, one mile from home I parked up took the battery home, charged it for an hour and recovered the bike. Steve
I presume the red charging light did not appear on the dash. This caught me out too first time as this little bulb had blown on my 916. If it is on and doesnt go off after starting, then this indicates that the battery isnt getting charged. The places to check are the yellow wires from the stator to the reg/rect. They run from stator to reg/rect inbetween the v of the pots. These get very hot and where there may be bullet or spade connectors, additional resistence may cause them to burn out. I had mine replaced with heavy duty wires and my stator rewound by westcountrywindings. I now make soldered connections only to the yellow wires to avoid this. Why ducati decided to place a heat sensitive elctronic part right next to the front pot exhaust header is anyones guess. Some heat shielding here helps. But not much. Whenever my reg/rect used to go it would sometimes seem to take the battery with it. Even if it was new. Birdies relocation is the best way to go, but Ive not had any issues since rewind and additional heat protection. I carry a spare reg/rect under my seat too as Im paranoid now. The mosfet shendingen is reckoned the best one, but im still on an electrex r51/55 (cant remember). Ill move to the better one when this one goes. Which it will. Eventually. Good luck.
Reading between the lines of your original post, it becomes more evident that your battery was flat when you were forced to a halt. You didn’t actually say so though.
Hi Coldrobba and all Really thankful for all the help and suggestions. Sorry for l g post! @coldrobba - no the battery wasn’t flat when I took it out on the breakdown day Wednesday - I had put a new optimiser on it overnight Tuesday and, as I mentioned it started absolutely fine and rode well until approx 12 miles of slow riding. @Birdie - this was only my second ride out on it (only got it the Friday before). First day it started fine and I only did about 30 miles BUT the lights were off. Wednesday (breakdown day) I had found the light switch and they were on. This fits with your thoughts on mileage before misfire starts with a fully charged battery. @bootsam - no the red light didn’t come on but I thought this was an oil pressure warning not a charging light? When I managed to restart it after the battery had recovered it came on when I switched on and went off as it was supposed to. Am I missing seeing a charging light - didn’t think there was one from owners manual? I can confirm that the battery is new and “optimised” to full charge. Now I have been investigating further today and have made some “progress” and had an Ah!Ha! moment as follows: All standard fuses OK 3 yellow wires NOT showing any sign of overheating. Reg/rect to stator connector absolutely fine - again NOT showing any signs of overheating. BUT the 40 amp fuse to the right of the battery (above the solenoid?) had blown. Therefore I’m wondering if due to the slow speed for 15 minutes or so caused the reg/rect to overheat and it didn’t like it so blew the 40amp fuse. I have got a new fuse and put it all back together but haven’t started it yet as I can’t get another one until Monday and wanted to to do some tests tomorrow. Can anybody suggest what tests I should be doing with my meter. I’m guessing fire it up: Check battery voltage without and with lights on - what voltages should I see approx? What else should I look for? Thanks again all Ken
The 40 amp fuse will have prevented the battery charging, start it up, you should have above 14v with a few revs across the battery terminals. Hopefully there isn't a problem and your fuse won't blow again. I wouldn't think the riding in traffic would have anything to do with the fuse blowing .
Many thanks Steve - will try that today and as you say hopefully will be OK - good excuse to get out and try it. Have you any idea why that fuse would blow though? Thanks again - really pleased with the help from all you guys
No idea why it would blow.perhaps a cable was shorted out while changing the battery? Hope it's OK with the new fuse. Steve
Hi Steve Started up fine and checked volts - about 11 prior to starting -didn’t quite get to 14 with engine running - was about 13 (old analogue meter not digital). Switched off and 40 fuse still OK though. Will take for longer run tomorrow, raining at the mo. Do you think not getting to 14 volts indicates a problem - I didn’t want to over rev it with just stood. Also, I’m wondering if attempting to start it with the optimiser plugged in and charging would have blown the fuse -I’m thinking I may have forgotten it was connected and tried briefly before my breakdown trip - do you think so?
Not sure wether your readings are correct, at 11 v it wouldn't have enough power to start it, I would expect a little over 14 v at around 3000 revs or so. A good battery at standstill should be reading around 12.7 v Steve
@Birdie Hi Steve Just to close this off ! Just tested again with a digital meter and got 13.3v at standstill (straight after disconnecting optimiser) and 14.4v at tick over so you were correct my analogue meter was wrong and needs calibrating. All good then All the best Ken
