Running 1500-2500w through a bicycle chainline is the opposite of reliable, much less bulletproof. You will either need a very heavy chainline or a hub motor.
Unless the OP thinks they are only going to use it for a week or two and give up on it, yes a good battery better: lighter, more reliable and cheaper than a cheap heavy battery you have to replace all the time.
I ride with the wife regularly (mostly on local trails) on our KMX trikes. It's been one of our favorite passtimes these past few years, and just keeps getting better.
I'm with otherDoc, a kmx with nice fat tires and a 500w+ middrive or big hub in the back would make a great beach ride, and as a bonus you have your own comfy chair built in.
If your budget is up to it, a 20 amp hour ping battery would give you the speeds you want and about a 30 mile range for about 15-20# of weight. 36v will get you ~20 mph according to http://www.ebikes.ca/simulator/ and 48v ~25mph. The simulator is pretty good at estimating speed, range etc. The...
The 650-1200w cyclone is a different (if closely related) animal because it's built for an external rather than internal controller. I know there have been a few people here who have bypassed/removed the internal controllers. A good place to start would be...
Most bikes/systems that claim to have a torque sensor actually just use a cadence sensor that just counts revolutions at the bottom bracket. Other than Bionx there are a few european and asian brands that use panasonic/bosch systems with torque sensors (as I understand it) or if you're looking...
Did anyone mention that rc batteries can catch fire if you abuse them? I'm not trying to scare anyone off, just pointing out that they are not as plug and play as LiFePO4. If you don't mind the extra work, there's a reason so many people here use them.
SK
My girlfriend has a 26.5"inseam, and we had no luck finding her a prebuilt bike that she liked. I converted an extra small trek 3500 (13") and that was ok. We didn't get a really good fit until we switched to recumbent trikes.
Your best bet is either to try a folder or find the right bike and...
My cyclone doesn't have many hours /miles on it. We pulled it off my girlfriend's bike because of mounting issues. When I have time it will go on my kmx because I already paid for it. Based on it's reputation I plan to run it at 24v which should get me close to 30mph in theory. If I end up...
If you go cyclone it won't be quiet, but their heavy duty double freewheel mount doesn't suck like the regular bike mounts do (at least on my square tubed kmx) on round tubes I have no idea. That kind of power will eat chains though, I'd almost suggest carrying an extra in your bag. As for...
I think the first two distributors you'll hear about here for LiFePO4 would be ping http://www.pingbattery.com/servlet/StoreFront for basic 2c packs or CellMan http://www.emissions-free.com/catalog/c1_p1.html for high discharge packs (A123). They aren't the only good suppliers, but many here...
Grin (ebikes.ca) offer infineon 20a and 35a controllers set up for 24-48v nominal. I can't say whether it helps the efficiency, but they're a very reputable source.
-SK