Hi I bought 999s off some guy who said it was working fine until he took it from the garage after 5 months of not using it. Charged battery started once and that was all. Charged again and again one start and dead. He then replaced it with one of those: When started engine was running ok he went for mot back on bike wont start. When i came to buy started off my car jump leads and rode home with no issues when arrived started once and stopped. Battery flat. Now my suspect is a cheap crap battery as i have never seen one of them and there is no sign of one in internet...but it might be something else. The charging voltage on dash displays 13,6 v when riding. Almost constant and jumped up to 13,7 at the end of the jurney. I have got pro batery tester showing (when charged) 12,8 v 9,9 ah... Is it down to cold cranking power? Somebody has had any experience? Thanks
My 749 battery voltage when riding is between 14.1 and 14.3volts DC. You may have a duff voltage regulator.
My 999 ran fine with 13.6v riding. Recently put extra earth from starter bolt to -ve battery conection and gained .3v.
It does sound like your battery is fkd but the earth wire mod also helps starter motor turn over better so recommend you do that anyway. I would also clean connections on starter circuit.
I've used a Rob Hunter battery before - their made reasonably locally to me around the Yeovil (Somerset) area according to Branson Motorcycles in Yeovil. Used it on my M600 for about 5 years with no issues. However (as with another different make of battery I had on my 900ss), eventually, even though the trickle charger indicated a fully charged battery e.g. green light, there wasn't even enough power to turn the motor over. I was told by an RAC mechanic that modern batteries are designed to give their 'all' up till the last minute and can then die without warning. A fully charged battery (once left standing for a couple of hours after having been charged) should read about 12.7v and between 13.5 and 14.5v with the engine running - any more and your regulator's almost certainly knackered, any less and you need to check out your alternator. See that attached state of charge table. Hope this helps.
well just made some tests while waiting for secondary earth cable(£3 on ebay) the current is around 6amps when turn the ignition on, obviously the pump starts first and it is much more but then stabilises to 6 amps (engine not started) is that ok or do i have a leak ??? heard about fuel filter clogged might get the pump taking more amps.. anyway - probably battery need changing first before any more research, what do You think about it? BATTERY LITHIUM MAGNETI MARELLI YT12B-BS DUCATI 999 S 998 2003 2004 2005 2006 | eBay Samurai this battery goes to 11.3 volts means complete crap i know a lot about alarm batteries i am fire and security engineer but bike batts need more crank power so i would think that is the issue. also can not find rob hunters batts specs anywhere.. it does not shine good light on the manufacturer
ok next phase - secondary lead works great however the battery is weak and i do not believe it can last enough to ride out. i will buy proper one to save my nerves cheers for help guys
I've had a few similar issues. I got a new battery, didn't help, I got the 2nd earth lead, didn't help, finally turned out the Regulator / Rectifier was dead, replaced this, running like a dream. But do note that 999's are notorious for having a bit of a hard time starting, ensure you NEVER pull the fast idle level prior to pressing the start button and hearing the engine start turning, this adds extra stress (extra fuel) and makes it even harder for it to turn. Also, I've had a dodgy start switch, you had to move it slightly to the right prior to pressing or nothing would happen, try those. hope this helps.
Maybe you know this, but in this bike the battery lies on the side, meaning you cannot buy any battery out there, it has to be one which will not leak and work well on it's side. I've had a bosch new battery which I've had to return as it, even though it didn't leak, it was weak. I found gell batteries are great and offer a bit more cranking power, that's what I use.
Thanks salmore. Could you tell me what volt readings did You have on running engine before and after rectifier replacement? I think it is dodgy battery anyway. Got my friends batt for couple of day will give it a test...
Before replacement running showed about 13.4 off showed about 11.3 or so and sometimes as low as 10.9. About a week before rectifier replacement while riding it went super wonky and started showing about 15.9 all of a sudden and then just said 'hi'. Replaced with a new battery to not much resolution. After the rectifier replacement (about £40 new from eBay) now off shows about 12.0 (which is odd as rectifier does not or should not affect it before you turn it on) and running about 13.7or 13.8. Also before I had to have the battery on trickle charger every 2nd day. Now I have not charged it for a good 3 months and same voltage still even though I only commute on it 5 miles so no long rides to give the battery a good charge. The battery I got is an mbatt gel type. Hope this helps. Note that if the rectifier is fried there could be a good reason for it which might be worth finding out before frying another one. For example when I replaced mine found oily water in one of the connectors... Turned out at some point must have been a hose leaking which was replaced but no one thought to check if any leftover water was anywhere -_-. Also point wanted to make was that i got an electric tester and tested my rectifier as per some YouTube videos to see if it is messed up and all reading showed up fine... Was not going to replace it... But already ordered a new one so thought what the heck... Turns out you cannot always test a rectifier as it could be a fault which appears only under load... Anyways chances are you've never had it replaced and these bikes were last made a while ago so guessing yours is at least 7 years old. Definitely worth replacing as they don't cost a lot. Maybe worth testing your stator as well just in case to make sure there is no surges or leaks of power to the case. Let me know how you get on
The stator has been tested and no problems at all. Now I have installed batt from my friend guess what? Starts OK every time. I kept it with ignition on for a good couple of minutes still fires up. The reading when running is constant 13,6 13.7 v. And finally I have charged the crappy one over night and it died after couple of starts. Will go for really good battery(my friends is some no name one) and should sort it out. If problem persist will get a new recto. Cheers anyway
Cool. Glad that's what it was. Although keep in mind that there might be a reason the old battery went down to hell. That reason might be a chappy battery which has outlived it's life or a failing rectifier which ruined it. Keep in mind that the symptom is not always the issue might be a good idea to replace the rectifier anyways just in case so that you don't have to go get a new battery in a month again, especially as I think the batteries are more expensive that the rectifiers good luck
The reason for the battery confusion was first the old battery was 7 years old and second the previous owner kept it i n garage for couple of months without charging.... Then was surprised after replacing for the "new " one. Of course will buy the rectifier as a precaution. Exactly the same as ignition stick coils in my old boxer BMW (recommendation from the manufacturer)
Hi just an update fitted new Yuasa yesterday. Dash shows 12.5v when ignition on. Cranks well and charging voltage is 13.6 constant. Looks like it was the battery. I am going to keep secondary earth on anyway.
