Originally Posted by
hopperja
I completely disagree. Generally freewheels are built around 7 speed clusters (or perhaps 6 or even 5). This makes for a more symetrical wheel, meaning it's stronger. You can use a larger gear cluster by upgrading to a cassette, but the hub will be more off center and thus the wheel will be weaker (the drive side spokes on a 8/9/10 spd cassette will generally be more vertical and will also be tighter tensioned= an imbalance between drive side and non-drive side = weakness).
I'm well versed in wheel building, and I guess with 14mm axles, you could just keep replacing the freewheels as they self-destruct, or spend some money for a quality one. I personally like the strength advantages and weight benefits of cassettes, but my touring/commuter bike has a 7-speed-only cassette body, which makes for a much stronger wheel (less dish) than 9/10 speed ones. I'm even thinking of picking up some NOS 7-speed cassette hubs to keep me going indefinitely. As long as they make parts for them...
Tandem hubs/wheels are generally stronger than regular hubs/wheels because they have either 40 or 48 spokes. The extra spokes make up for their inherent geometrical weakness of the more off-center wheel.
The cheaper ones just have more holes, but the better ones will have sturdier axles and bearings as well. This is a budget bike, though... those wheels would cost more than the bike itself.
Also, a 7 spd freewheel often has the gear range of a 9 spd cassette, with only slightly larger steps between gears. Unless you're racing and cadence is of utmost importance, the steps most likely won't matter.
Range has nothing to do with how many gears it has, you can get cassettes or freewheels in a huge number of combinations. If anything, a cassette will have wider range because you can go all the way down to an 11t cog, while freewheels are usually limited to 13 or 14t. I've seen large cogs on both up to 34t. I'm not advising cassettes for performance issues, it's strictly for mechanical durability of the mechanism. I've destroyed a LOT of freewheels, have yet to kill a cassette hub. I think a 7-speed cassette is just about perfect, for reasons you specified (less dish) and durability (not bending axles or destroying freewheels).
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As an afterthought, they never made 7-sp cassette tandem hubs, or disk hubs, for that matter. You could actually convert a newer hub to use an older freewheel body, and re-space the axle... but that's a lot of work. What would be easier is using one of the newer downhill MTB hubs, that have 12mm through-axles and ISO disk mounts. Could probably get away with 36 spokes with a hub like that, with off-the-shelf parts. Most disk hubs have the left flange a little more inboard, which helps with dish as well.
Blah. Sorry for geeking out on wheel stuff.
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