Charging Cell Phone while riding

Greetings!, I have a 1975 Z1-B 900 and a 2003 Harley Heritage Classic, I also have a Samsung Galaxy III Cell Phone, frequently my cell battery is dead when I have taken a long ride on either bike . I am looking for a safe way to charge the Cell battery as I ride ( With phone off of course) I went to local Harley Dealer where the Parts guy suggessted a USB cable /Adapter that would connect to my Battery tender cable on my bikes battery ( Got Tender Leads on both bikes ). My question is this, is there a danger of overcharging the cell phone Battery if I use this USB adapter to Battery tender Cable arrangement?? I have replaced the stock regulator on the Kaw with the New Electronic Solid State system from Z1E. I know I could get the Universal Power supply cable which would also fit my Battery Tender cables then purchase a Car Charger to plug into that etc. etc. The USB Cable direct seems to be a simple solution, I am just worried if that is a "Controlled/regulated" charging method??? I looked and it seems I could just put the charging cables under the seat ( Kaw ) /or in my saddlebag ( Harley ) as I ride keeping it and my cellphone safe. Any comments?,Thoughts?
Thanks
Ed

With the new Reg/Rect you shouldn't have any surging problems. I have a cigarette lighter on my bike and use it for charging my phone and now for my bike cam. I'd rather go through the plug in charger than to direct wire in. Better the charger burn out than my goodies.
Steve

ed,
i have one of these
www.amazon.com/Battery-Tender-081-0158-D...harger/dp/B00DJ5KEF4
that i use between my 04 firefighter road king and my 80 z1r for a galaxy s3.
never had any trouble with overcharging.

super handy.

leon

swest wrote: With the new Reg/Rect you shouldn't have any surging problems. I have a cigarette lighter on my bike and use it for charging my phone and now for my bike cam. I'd rather go through the plug in charger than to direct wire in. Better the charger burn out than my goodies.
Steve

Same here, I got one out of a wreck or get one from the wreckers. Plug mounted under the seat and run wire/s under tank up to the bars.

531blackbanshee wrote: ed,
i have one of these
www.amazon.com/Battery-Tender-081-0158-D...harger/dp/B00DJ5KEF4
that i use between my 04 firefighter road king and my 80 z1r for a galaxy s3.
never had any trouble with overcharging.
Thanks Leon, Thats EXACTLY what the Local harley dealer had in their Battery tender Supply Section.
I apprecaite the input!
Ed

super handy.

leon

Harvey1327 wrote:

swest wrote: With the new Reg/Rect you shouldn't have any surging problems. I have a cigarette lighter on my bike and use it for charging my phone and now for my bike cam. I'd rather go through the plug in charger than to direct wire in. Better the charger burn out than my goodies.
Steve

Same here, I got one out of a wreck or get one from the wreckers. Plug mounted under the seat and run wire/s under tank up to the bars.

Thanks Steve and Harvey!!
Ed