Struth!! Thanks everyone. I like Coffee's idea.. And I've seen them in large car batteries. A seperate smaller battery contained in the main battery with just enough for one start... Wonder if there is something like that out there? Anyone? The capacitor is a good idea as well? What size/type are you using?
http://www.ktmcyclehutt.com/ktmstore/2009_ktm/77311053100_lg.jpg Just throwing it out there. A 6 amp battery that weighs half or so what a regular battery weighs. VERY expensive. But it does show that there are many options.
Does your "Battery Tender" have this wonderful feature? "Before you connect the "BatteryMINDer" to your battery, test the battery for any shorted cells and check the voltage in the battery. The battery has to have a minimum resting voltage of 11 volts before the unit will turn on. Resting voltage means that the battery has not been charged or discharged within 8 hours minimum. If you test a battery that has not rested for at least 8 hours, you will get incorrect, inaccurate readings. 1. Test your battery first before you connect it to the BatteryMINDer. See page 2 for more information on testing the battery. See page 5 for more information about installing the BatteryMINDer inside or outside of the equipment. 2. Check the voltage in your battery. If the resting voltage is less than 11 volts, use a regular charger to charge the battery to full voltage before connecting the BatteryMINDer to it. The BatteryMINDer does not turn on if the voltage is lower than 11 volts. 5. The green indicator lights when the proper connection is made. The green light is powered by the battery and lights up even when the BatteryMINDer is not plugged in an electrical outlet. 6. Plug the BatteryMINDer into an AC electrical outlet as soon as possible after you have made the connection to the battery. Note: The unit will use the power from your battery and drain the battery if you do not plug it into an electrical outlet. 7. The red indicator lights to show that there is AC power going into the unit. If the red light does not come on, check you outlet to make sure that it is switched on. The red light stays on unless the outlet is switched off or the BatteryMINDer has failed." Don't ask me if I took those lights for granted once or twice! 11 volts to charge, eh...
My Battery Tender Jr does not have that 'feature' - it will slowly try to charge a battery safely from any condition. It just charged up a dead car battery (10V -> 12.5V) but it took a few days. It has (tried) to charge batteries with 2 shorted cells & discharged... 5-6V....but could not do so - but gave a valiant effort. I tested it over a wide variety of conditions with many batteries, checked the voltage every hour while connected - absolute perfection. Highly recommend the Battery Tender Jr. I used to design automotive test equipment a few lifetimes ago. They are only $20 on sale.
