I have a Varta YB14L (14Ah) battery and am thinking of replacing it. Is it possible to fit one that is higher capacity (and that will physically fit in the holder)? I have a heated vest and heated grips (it's cold here in the UK right now!). Will a higher capacity affect the reg/rec or anything else in the circuit?
Thanks.

 

Forgot to say Merry Xmas and a happy new year to you all!

 

Yup putting in a higher capacity battery usually will involve changing to a bigger rectifier and alternator

 

From my understanding, putting in a bigger battery will just increase its duration. Like a AA battery is just a smaller version of a D battery, both are 1.5 volts, but the D battery will last longer.

Automotive batterys are 12 volts, alternators put out 14 volts, because the higher voltage will always travel to the lower voltage, charging the battery (which is 12 volts).

So the only thing your bigger battery may solve is being able to run components longer with the engine off, or short-term usage of a higher amp component. In your case, your heated grips MAY require upgraded charging components to keep the battery charged. You can actually calculate draw by adding up the wattage of each component, I believe I saw this in the FSM, just add your aftermarket stuff to whatever is being used at the moment. Stuff like horn, brake light, and turn signals may not have to be added, since you use them for a short duration.

 

All of which begs the question, what is the output of a 1000F alternator in watts? Before we can figure out how much reserve we have after adding things like heated grips, heated vests and larger wattage or seperate lights, we need to know the total output of the charging system.
Anyone know? I couldn't find anything in the manual.

 

LOL, got the manual for 87-88 sitting in front of my now...standby...

Alternator: 350 W/5,000 rpm

Lights:
Headlights High/Low - 60/55W
Position light - 2 cp x 2
Tail/Stop light - 32/2 cp (SAE TRADE No. 1157) x 2
Front turn/running light - 32/2 cp (SAE TRADE No. 1034) x 2
Rear turn light - 32 cp (SAE TRADE No. 1073) x 2
License light - 3 cp
Instrmt lights 87'/Aftr - 3.4W x 4 / 1.7W x 4
Oil Warning - 3.4 WL
Neutral Indicator - 3.4 W
Turn Indicator - 3.4 W
High Beam Indicator - 3.4 W

Phew, that was some school work...

 

I'm not sure what "cp" is referring to

 

Just remember those figures are for the bulbs themselves. There is always some extra watts used due to old wiring, bad contacts etc.

 

CP = candle power
a rather oboslete way of rating brightness in leu of watts or lumens

Merry Christmas all!!

Fred

ps Santa brought me a new riding jacket and boots! (GOOD Santa!) now if the WX will cooperate I'll road thest them.

 

A larger battery will help, or to be moremore correct- help in some special situations, and you don’t need to upgrade the Rec/Reg or alternatorbecause of thelarger battery thatwill still be in the same capacity region. The situation where the larger battery will help is if you go down to idle quite oftenwith all the extras (vest/grips) switched on. The charging current from the alternator is low on idle and the larger battery will thenhelp to keep the voltage up for some time, so there is a farbetter chance to start the bike again compared to if you have had a smaller or bad battery. However, for continuous use of the extra stuff, the alternator must be capable to provide all theextra current draw needed, the battery cant help you with that, other than for a limited period.

So, a larger battery will not destroy the alternator or Reg/Rec, but too much continuous current draw will. As said in posts above, check that the extra watts consumed by the vest and grips, together with the front and rear light wattage is well within the capacity of the alternator. You don’t turn right and left and brake and get oil warnings and neutral indicators simultaneously, so there is no need to add all consumers.

Add the watt figures for headlight and rear light plus the vest and grips, if the sum is not more than250 to 300 watts you should be fine. And a fresh and larger battery will help to keep the bike running properly. I also believe thata well reputadedquality brand battery with standard rating, will provide more capacity than a cheap replacementeven ifthe later oneis rated higher.

Merry Christmas and Happy New Year back.