I’ve had my Breva 750 for a couple of years now but since about a year ago I’ve had several problems with the bike starting and the battery holding its charge. Whether or not these problems are linked or just typical Italian reliability I don’t know. I’ll run through the problems:
At first when it wasn’t starting properly, it seemed as though the battery wasn’t holding its charge but eventually I took it to the guzzi shop in Cambridge and they replaced the started motor which was faulty so it was draining the battery every time I started it.
I also replaced the battery at this time in case the faulty starter motor and frequent battery dying had killed it.
Before realising the started motor was at fault I put a new regulator on in case it was that so it can’t be that. I also cleaned the connectors to it.
Since then I have been coping with just charging the battery every so often before the battery went dead. However it has got to the point where I need to charge the battery every 1-2 weeks which is making it unusable. The battery either doesn’t seem to be holding the charge or the regulator isn’t charging it enough while in use.
Now I have 3 questions for someone
What voltage should the alternator be putting out at idle and while revving. Mine doesn’t make much more than 14 while revving it.
Where is the earth as I am thinking I should clean it up a bit
Do people think the standard breva 750 battery capacity is sufficient enough?
Thanks in advance! Any help would be greatly appreciated!!!
My wife has a 750 breva and they do have a constant power drain on the battery we keep it on a optimate charger and don’t have a problem. The first question is do you use it for longer runs or is it only used for short runs if so them you will flatten the battery if left standing the hand book recommends removing the main fuse to stop the battery discharging any more than 14 volts and you will over charge the battery and boil it dry. Motobatt do a AGM battery with more cranking power but we have only ever used the standard battery’s all be it a branded make yuasa
Keith8 Valve Eagle2013-12-20 08:36:55
Maximum charge should be 14.5 volts.14 volts should be sufficient.My Westco from taynaltd has lasted 18 months without being recharged so is big enough.The earth goes to the rhs loer crankcase.What is your daily milage or average journey milage?
As said above, there is a parasitic drain on the battery all the time the bike is standing, though this is small, it will discharge the battery in 3 to 4 weeks, sufficient that starting may be difficult.If you are getting 14 volts when the engine is revving (headlight on?) then all is fine in the charging department.How long are you leaving it between rides? If it is 3 weeks or more, then you will have a discharged battery. If it is all happening in a couple of days, then there is something amiss.
I usually only do between 5-10 miles on it to and from different work places. Which I have thought would contribute to the battery going flat so quickly but the time between me having to charge it has got more and more frequent so I assume something is getting worse perhaps. However even when I do longer trips, say 50-90 miles it still does seem to run the battery down way too quickly.
I also use the bike every other day on average.
As your all saying that the voltage it is putting out is normal, I assume the alternator shouldn’t need replacing?
I’ve also had a problem with the tick over speed, which seems to sort its self out every now and again. It is more often than not, too low when not moving at lights for example, meaning I have to keep the revs up ever so slightly to keep it from stalling. It is ok when in neutral at these times however. But, after a few weeks of it being low for example, it then goes back to normal and ticks over perfectly, which perplexes me completely as I’ll not have done anything to it at all. Unfortunately this doesn’t seem to be 100% linked to the battery charge as its still too slow even when I’ve just charged it!
Do you spend a lot of time waiting at traffic lights, also I presume you have all your lights on all the time, speshly at this time of year, these are the sorts of things that may prevent battery being charged properly. Ergo even 5 - 10 miles of ‘urban’ type slow riding with frequent stops is probably not good enough. Don’t forget starter motor is used at the start of each trip and ideally you want to put that lost charge back in before the next time it’s used.
Ian does indeed have an immaculately looking B750. To set the Throttle Positioning Sensor (TPS) you need special computer software and a cable to link to the bike. If you ever adjust the Throttle Body balance, the TPS must also be reset too.If the TB balance is out, and thus the TPS setting is wrong, it will affect the running of the bike.However it will have no effect on the battery charging. The alternators on all these bikes are crankshaft mounted, so if you spend all your time riding at no more than 2000 rpm, the alternator will probably not be charging the battery enough to replace what the starter motor took out especially as the headlight is always on.
Off topic but IMHO if you run a Guzzi at 2,000rpm all the time you won’t be running it for long. The damn things demand to be revved.But Brian has it right.
I’ve also had a problem with the tick over speed, which seems to sort its self out every now and again. It is more often than not, too low when not moving at lights for example, meaning I have to keep the revs up ever so slightly to keep it from stalling. It is ok when in neutral at these times however. But, after a few weeks of it being low for example, it then goes back to normal and ticks over perfectly, which perplexes me completely as I’ll not have done anything to it at all. Unfortunately this doesn’t seem to be 100% linked to the battery charge as its still too slow even when I’ve just charged it!
Thanks for all your replies!
Luke.[/quote
Just an observation, nothing to do with your electrical problem but it sounds like your clutch may be dragging a bit.
‘I’ve also had a problem with the tick over speed, which seems to sort its self out every now and again. It is more often than not, too low when not moving at lights for example, meaning I have to keep the revs up ever so slightly to keep it from stalling. It is ok when in neutral at these times however.’
Mea culps, I misread.Yes dragging clutch seems likely.The adjustment free play at the handlebar must be no more than 4mm.This also makes finding neutral easier, and the gearbox slicker.
Sorry for my late reply! Too much eating and drinking for christmas and nye .
I think I may buy a new (new or used) alternator and see if that changes anything, as I have thought that the short journeys on it probably haven’t been to its liking.
Re the clutch, I shall have a look at that, thanks for your suggestion!
before you buy a new alternator work through the system and remove all chances for bad connections and voltdrop. I’ve listed them before on the forum, but its not appearing on the search. quick list: - regulator connector under front of tank, gets wet: clean and grease (note will be live with ignition off if you dont disconnect at battery) - main earth point: the factory decided it was a good idea to clamp the ring terminals onto a painted casing surface using a ferrous bolt in an aluminium casting where there is a big clearance hole to collect water, and didnt use any grease. You know the routine, take apart, remove paint under terminals, emery / wire brush everything until shiny, assemble with excess of electrical grease / vaseline.- 30A fuses on side of battery - one of them is for the charging circuit, they get wet, clean fuses and holder, assemble with electrical grease/ vaseline- check the 2 pin power connector in loom above battery, should be OK, note that its useful for disconnecting bike electronics drain if parked up- battery terminals - clean battery posts and the cable terminations with emery paper / wire brush, assemble with electrical grease/ vaseline. - check all cable ends for signs of any green decay going into cable insulation disconnect battery before working on charging circuit, the circuit is permannetly live, and if the generator is spinning there is big enough AC in the regulator connector to damage you Using a voltmeter yopu can check regulator output voltage, and work back through the circuit to identify any bad connections causing voltdrop.
Rereading the first post again, worked alright now doesn’t after a couple of years, this may just be corroded connectors problem? As said above battery connections need to be perfect, only way to be sure is take them off and look underneath
