Hi @RanzQ!

The reason this is happening is that the x axis in this case is index-based. By specifying max: 5, you tell C3 to ensure there's space for five data points. If there's only one (as there is in this case), it'll compress it into one side.

There totally is a bit of weirdness with min and max in the example you've given, though — data1 is half as wide as data2, which doesn't make much sense, even if you're using it oddly (That is, you probably shouldn't specify min/max with indexed axes, C3 will take care of that generally. Min/max are really only used with numerical axes.).

Attaching screencap. @masayuki0812, not sure if I should tag this as bug or invalid?

Also, can confirm it occurs in 0.4.9, not sure what version the website is currently running.

Edit: Going with bug for the moment, feel free to re-tag.

I made a temp fix by modifying getMaxDataCount to prefer axis_x_tick_values length if specified and greater than maxDataCount:

c3.chart.internal.fn.getMaxDataCount = function () {
    var $$ = this, config = $$.config,
        maxDataCount = $$.d3.max($$.data.targets, function (t) { return t.values.length; }),
        tickValues = config.axis_x_tick_values
    return tickValues && tickValues.length > maxDataCount ? tickValues.length : maxDataCount
};

That fixed the width problem I was having. For the min-max bug I just adjusted the min and max in case of one datapoint and it gets centered. Not sure if that affects other charts.

I'm using this on a timeseries, min and max work well to fit my domain to a specific time range.

Thank you for looking into this. Yeah, it's not intended, but it's a bug and width of bar should be computed correctly in this situation. So, I fixed by introducing tickInterval, which returns the length between ticks, and compute the width using this function.
I'll release this in the next version 0.4.10 shortly. Thanks.

0.4.10 has been released, so let me close at the moment. Thanks.