Electric Bikes - 5 speed casettes to 7 speed?

The brushless gearless rear hub kits I've seen seem to always come with a 5 speed cassette, at least the ones in my price range. I can't remember the last time I've even seen a 15-speed bike for sale. They are all either 1 speed, 7-speed, or 21+ speed nowadays. Is it possible to put the 7 speed cassette from the original rim onto the rim with the hub motor? Or are you stuck with 2 less gears in the back? Or am I missing something else?

Like this kit (http://www.smartbikecanada.com/26rearwheelkit.html)for example.

I'm sceptical that a "5 speed cassette" even exists. Thats most likely a freewheel, which is a completely different thing, and not interchangeable with a cassette.

However, the answer (given my presumption that this is freewheel) is that so long as you have the clearance within your dropouts to accommodate the new freewheel then you can use 6-7-8 speed freewheels without a problem - from my experience, 7 speeds will fit in just about any frame (and can be had just about anywhere you can buy bikes), while 8 speeds requires some special ordering and is a bit too wide for some bikes but on others it can be made to fit (my system is running an 8 speed freewheel, it required the addition of a small washer, but wasn't hard)

In order to change the freewheel over, you need a chain whip and a freewheel remover with a hole in the middle large enough to fit the axle through (e-bike motors don't work with every remover, check ahead of time) - a bike shop can just do it for you too.

(Should that somehow *actually* be a cassette and not a freewheel, then the answer is still that you can likely change it, but the first stop on the list for cassettes is 8-speed, and getting it to fit may once again be a problem. I'm more convinced that the website has it mislabelled)

Yes.

Most of the hub motors out there, use regular screw-on freewheels. Just take the 5s off, and put your 7s on. Remember, yours needs to be a screw-on freewheel, not a cassette.

If you have a 7s cassette, then you can purchase a 7s freewheel to match it without any problems. They are only about $20.

Patriot is correct.

But also be aware that for many e-bikers, low gears / lots of gears aren't really necessary. If you are pedaling along with your motor, it's likely that you'll be able to cruise up fairly steep hills at a speed where you'll want to be using your middle gear in back, not your smallest ones. Of course, this assumes that you make sure to have enough battery power to use the motor on all the uphills. (never been a problem for me)

JinbaIttai: I looked at the page that you suggested. It does say Cassette, maybe so. But re: cerawa's comment, with chain drive bikes like eZip the problem is that there is not a HIGH enough gear. You can't pedal to keep speed up on a down hill to prep for the following uphill. At about 18 mph legs are flying. That's the reason I added gears. I'm not sure it's the same for hub drives. Maybe they chose well. Or maybe you just need a different cluster of 5 sprockets.