Dual Battery (Oilhead)

[Justin B.]

I have just one of those batteries in the RTP and it works fine.  In fact, now that I think about it, I have one of those Universal 18 AH batteries in every bike we have - 2 R65, R100RT, and R1150RTP.

[Barry]

Just replaced the filter and oil yesterday, went to full synthetic Mobil 1 V-Twin 20w50 and no noticeable increase in starter speed .  

Just read back over the whole thread. I wonder if one battery and  10W50 or even 5W50 might have done the trick for very cold weather starting and all year round use - if there is a suitable oil available.

[Tony Smith]

The specified battery is a 12V-24A monster that weights slightly less than a small fishing boat's anchor. The battery is currently in good shape but I have no idea how old it is.  

My question is if an R65-sized battery, like the 12V-18A Gruber would be a workable replacement? Less weight and I see no reason it wouldn't power the Bosch starter as well as the smaller battery on my R65s.

If I may jump in. The R65 sized battery will work perfectly with a standard compression R100, after all the R80 runs the same battery as the R65.

However, oddly enough I've always found that the larger sized battery was easier to find at bargain prices than the smaller R65 one, the reason being that the size factor is used in a number of small cars,  I guess your mileage varies and all that.

I'm running a Gel Cell battery in the R65 and thus far I am very happy with it. I was initially  a bit worried that the charge rate might be a bit high, but then I remembered that the airhead has only got 280watts to play with on the best day it ever had and that is not going to overly stress a gel cell.
 
No leaks, no water to be checked and topped up and if i ever feel like moving the battery to under the duck tail, it will not mind being on its side. The only drawback is the unfortunate "fall off a cliff" failure mode.

[Bob_Roller]

Got the new batteries installed this afternoon .
One of the old batteries was bad, would not hold a charge, but surprisingly, the other battery is still in good shape .
Put it on the battery maintainer and it was at full charge in 20 minutes, I put it in the Guzzi .

[wa1udg]

Resurrected this thread .
Well, two years later and the starter is sounding a bit sluggish and the battery maintainer doesn't stop charging the batteries, never gives a full charge indication .
Just ordered two more batteries this afternoon .
So, I didn't get any more extended battery life with two batteries installed .
Just replaced the filter and oil yesterday, went to full synthetic Mobil 1 V-Twin 20w50 and no noticeable increase in starter speed .

 Just a polite suggestion.... Rotella T6 5W 40 for the winter.  20 bucks a gallon at Wallyworld.  JASO MA rated.  Drain it in the spring and use it in your lawnmower.