Help please loss of power and then cut out

[Benc30]

An yes i switched to reserve

Ok rode for the first time in about a year with lights on (usually just use side lights), was loosing power thinking i was running out of fuel pulled up a junction and it just died... dim oil light... tried the starter and it was dead, so switched off my lights and bump started it and it ran fine...... battery should be fine its not that old, ive got the bike on a trickle charger now, but after sitting for 6 months without the trickle charger it started fine and was fine for 25 miles or so.

Would i be right in guessing its probably the regulator/rectifier if this is the case being a uk spec bike do i have to make sure the new reg is uk spec or does it not matter. and can i test it to make sure if its goosed or not?


Many thanks
Ben

[wullvfr]

i dont think it matters with it being uk spec......the best way to test the charging system is get the bike going and using a multimeter check what the charge rate is at the battery whilst the bike is idling at 5000rpm.it should be between 13.5-15.5 volts.if its not within this then there could be a few possibilities,but start off with this simple check first.

[fastdruid]

Sounds like charging to me, exactly the same as our NC35 (except without an off switch for the lights and not realising I ended up having to push).

Simple test is to rev it with the lights on and see if they brighten. Of course if its dead already that wont help.

To test it properly you need a multi-meter.

Charge up the battery, see if it holds a charge overnight[0] if it doesn't then it's battery[1]. Stick a multi-meter across the battery, start it, the voltage should be ~12v with the engine off ~13 with the engine on at tickover rising to ~14 at around 5kRPM. I don't have the manual at hand to get the exact figures but I'm sure some one else will.

If the voltage drops then you have no charging, it could be the alternator coils though and I can't remember the way to test those, I think you measure between each of the connectors and it should be ~50v across each one but that could well be wrong. Seeing as the reg/rec is the normal thing to go though chances are that its just the reg/rec.

http://www.electrexworld.co.uk/ List a different model number for the NC30 UK model so it looks like it is different.

Druid

[0] I had one battery which would have 12v just off the charger, connect a multi-meter and you could watch it drop about 0.01v a sec. It's probably fine from how you describe it though.
[1] That it started OK after a while sounds as if its fine, although don't leave the battery discharged, they don't like it and it may have killed it if you left it for any time in which case it could *now* be reg/rec and battery.

[wullvfr]

if the reg rec is goosed then the charge rate will drain the bat down to below what it was in the first place.......if its the staor windings like druid says then the charge rate might be above the batterys voltage whilst switched off but not enough to power the bike and lights.....this happened to me and the bike would be fine so long as i didnt use the lights coz the battery was getting a charge but when i used the lights it was draining faster than the charge it was getting.do the charge rate test first but if you want to test the alternator then disconnect the connector that comes from the alternator over to the right handside and using a multimeter set to ac volts....you need to take three seperate readings whikst the bike is idling @5000rpm and they should all be above 50volts as druid says,if any are below or even if one is a different reading from the other two then the alternator is goosed...... :D :D :D

[fastdruid]

and using a multimeter set to ac volts....

Lol, forgot that important bit, yes multimeter set to AC to test the alternator. :D

Druid

[fastdruid]

http://www.electrexworld.co.uk/ List a different model number for the NC30 UK model so it looks like it is different.

Although having another look they list the year as 1986 and don't mention that it's an NC30.

Druid

[Benc30]

Thanks for all that info folks, ive got a meter so ill check it out asap. if its the alternator is this an easy thing to change? ill be honest and say i dont even know where its located

[wullvfr]

yeah it is an easy job if you have the tools.........do you have a manual??????you will need a rotor puller whch is the only downside to changing the alternator.....if you need more info on doing it then give me shout on my email and i'll help as much as i can.

[jo]

sounds like you have the same problem as I had last night these NC30 electrics are a bastard

[Benc30]

its the first problem ive had in 4 years so im not complaining

if i need a tool to do it ill just go and buy one, nothing worse than trying to do a job with out the right tools