Megablade - Motor-bike battery doesn't last 1/2 hour at night?

[madmarkymark]

Calling all BEC / Megablade owners...

My Westy is great except for the lack of electric juice it has.  I have replaced the rectifier once (for a new Blade one) since the last one caught fire  .  The new one came with a heat sink as part of the unit, I have thermally bonded it to the aluminium panel is sits on and have added a secondary heat sink next to it.

However, it still gets v v hot.  I can only drive for a maximum of 30 mins with headlights on before the car is out of juice and cuts out.  I can drive for longer on side lights (scary) and there is no issue at all with no lights - not much use for the long winter nights...

The battery seems to hold its charge fine when the car is not being used (I have checked it - and it seems fine). 

Has anyone else had this experience???  Is it the rectifier again (I think the 04 onwards CBR1100 is slightly meatier) or should I just buy a new battery ... or do I need to do both   

Any advice would be greatly received!  Madmarkymark

[Hairy Santa]

it would seem that the heat sinks are receiving all the juice and none is getting through to the battery, not that I know anything re your engine

what voltage are you getting across the battery
(a) before startup
(b) once the engine is running

there should be a few volts difference (upwards) once running,  if this is not doing this then your battery is not being charged and will go flat

[Iainl]

Have a look at the condition of the connectors (the one that plugs into the rectifier and also there maybe one at the other end of the same cable) mine had burnt and left brown crispy bits behind, this may effect the charging, it's a quick an easy check and fix if needed,

Cheers,
Iain

[paintman]

Have you got an old Amp guage you can rig up, then borrow a good battery and see if thats discharging.......least it will eliminate the battery      

[Daley Down Under]

When mine burnt out I went for a non genuine heavy duty one from eBay which dud the trick. Agree with Santa - check the voltage with engine running and not running as well.

Good luck

Adrian