No problem Joe we are all trying to help out.

kev.. a`l be doin whit ye say tomoro..........

Hi Kev

John's around and borrowing my volt meter.

He still has the old battery on the bike at the moment

Battery at rest 12.6v

battery at 3000 rpm 12.85v which seems a little low

Any suggestions as what to check next

Thanks

Yeah, something doesn't sound right there.

Generally, for a battery on a bike to charge well you need about 13.8 - 14.4 volts.

When the bike is running, thats what you should read across the battery.

The fact your not getting that when the bike is running suggests that there may be something up with the charging system.

Not necessarily the alternator, but regulator/rectifier more likely.

Rectifier consists of (generally speaking) 4 diodes that turn an AC current (alternator) into a DC current (battery) and the rectifier controls the voltage at which this is done but they're usually all 1 kit.

I would suggest Stumpy, I believe the regulator/rectifier is on the left side of the bike with a huge heat sink and a wiring loom heading do it, held on with a couple of bolts.

To check its that, you could remove yours and try it on Johns bike, then test the battery voltage again with the bike running?

I'm not too sure if the wiring loom connections are the same, but they should be.

That way then it eliminates the regulator/rectifier from the chain.

Many Thanks

One small issue, I no longer have an XT so I can't swap the r/r

However we're further ahead

I assumed you had one, DoH!

Well, personally, that'd be the next thing I'd check at least.

@ john and off topic:
you may find your tail light lense here:
http://www.oemmotorparts.com/oem5.as...-XT-X-660-2_BR

Thanks JOe

ave now fitted a new battery tonight,,, afetr fitting it , it wouldnt start, it just clicked.. the old one thati took out at rest was 11.5 v.. the new one was 12.5,,, but wouldnt start it just clicked away,, then i tried jumpleads from the old battery to the new one.. an it was hesitant, but started,, once started i took the leads off, but th eheadlight was dim an got brighter as i revved it, the dash light on tickover was wavering,,, till a touched the throttle, an it seemed ok.... i then switched it off,, tried startin again...no joy ??? its a brand new battery,, it was startin wi the old battery in wi less volts.???? it says when i filled it with acid, it was a dry cell batt.. it said DO NOT CHARGE fur at least 24 hours....WHY is that.??? will it peck up do you think if i jump tae get goin then then keep it goin fur a wee while,, to charge it up a wee bit that way...??? I thought it would start up fine no worries.... but its threw me off now,, the new batts NEW.??? any help please...

John I find something very strange here.

If you've bought an original MF Model CT9B4 one or an exact aftermarket copy then these batteries should be the gel type sealed, hence maintenance free throughout their life span, infact you must never had needed to refill any acid or charged it up 24hrs prior to fitting.

This might be the wrong battery and I would send it back if I were you to prevent frying your bike.