v4 engine novice

[NC35]

reading 12.2 volts after takign it off charge, still reading 12.2 / 1 volts when connected back to the bike but when i turn the ignition on we had oil lights then i checked the voltage and it was reading barely 3 volts so i am guessing either a duff battery or something is seriously draining the voltage.

That's not good at all. Assuming we are speaking sealed lead-acid as fitted to the NC30 as standard, a fully charged healthy battery should read greater than 12.8 volts after being at rest for two hours or more. If you have 12.2 volts maximum, then there is a cell failing, probably due to an internal short circuit.

Did you buy the battery yourself and if so, did you add the acid then charge it as per the instructions? The reason I ask is two-fold - can you be sure the battery is really a month old, or did it come off the shelf ready to go in which case it could have been sat on a shelf for months, possibly years?

[pugparcels]

hi the batter ywas brand new and i had to fill it myself etc.. i have done many batteries before for all manor of bikes. I still believe this battery is a dead horse. The strange thing i it was tested at the garage under load etc and all appeared to be fine. They are generally a good place ( though a bit expensive ) and the chap i am dealing with has been there 30 years and seen me grow up through a vast range of bikes.

but she has had now all of the below parts replaced with known good / working parts

reg / rec
starter relay
complete loom
ignition / starter switch

the starter motor has been checked and is working
the carbs are clean and running on all four

[NC35]

I agree, as I said earlier, 12.2v fully charged is not good at all, and if it drops to 3v with even a small load on then it's symptomatic of a dead short in one of the cells.

Also, if there was something seriously draining the battery, you would be getting loads of sparks and stuff when connecting the battery.

One last stab in the dark - have you checked the earth strap, i.e. the lead from battery negative to the frame, is in good condition and making a good clean connection at the frame? Your descriptions do seems to point towards an earth fault of some description also.

hi the batter ywas brand new and i had to fill it myself etc.. i have done many batteries before for all manor of bikes. I still believe this battery is a dead horse. The strange thing i it was tested at the garage under load etc and all appeared to be fine. They are generally a good place ( though a bit expensive ) and the chap i am dealing with has been there 30 years and seen me grow up through a vast range of bikes.

but she has had now all of the below parts replaced with known good / working parts

reg / rec
starter relay
complete loom
ignition / starter switch

the starter motor has been checked and is working
the carbs are clean and running on all four

[pugparcels]

the negative connection is good and has been checked as well. Just so i am not being stupid and the fact i also have no manual for her as of yet and am workign in the dark abit, how many earths are there on her just the one from the negative or is there anymore hiding in a dark corner?

if there was something draining the battery what could it be?

on another note the laser can i mentioned earlier from my blade is about 10 inches long with no baffle and a 75mm inner core, if i fit this to this nc30 when she is properly running is this going to be seriously loud as it was loud on my blade but this engine is a different beast.

[NC35]

Off the top of my head, I believe there are two earthing points - the main one, and one near the right-hand side fairing mounting bracket. I can't say for sure though, I expect someone who can remember/does know will confirm this.

There is nothing I can think of that would cause such a massive voltage drop you describe. And again, if there was, you would get loads of sparking when connecting the battery.

Can't say about the exhaust - sorry!

[CMSMJ1]

There are earths at the left front coil mount and also the battery neg lead.

the exhaust will be bloody loud if on a half system but possibly less offensive if on the cut down original - depends how much of the bafflin you smack out of it

[pugparcels]

ok just won a haynes manual from ebay for £3.71 so this all being well will give me more of a chance. i will check the front left coil mount in about an hour when i get back.

[pugparcels]

ok, have had the battery on charge for 24 hours checked the voltage before putting it on the bike and showed 13.3 volts, have just tried her on the bike and tried to fire and she started, the battery after i stopped the engine showed around 12.4 volts and kept increasing so i think we have solved the problem!!

i will check the battery first thing in the morning before i go to work to make sure the battery has not lost power again. i will let everyone know what happens but hopefully this is it!

thanks again to everyone

[pugparcels]

ok checked the battery this morning, still reading over 13 volts, tried to fire her and she started, checked voltage once i stopped the engine and read 12 & a bit volts and again was still climbing so i would say all sorted.

thanks again to everyone who had information to offer.

[CMSMJ1]

Bonus. Good to hear it is all sorted.