Bike fit comparison: Dahon Vitesse T20 vs Giant TCX SLR 2

It took some time and a fair bit of tinkering with parts, but I’ve finally dialed in Bino and Hyro‘s bike fits as closely as possible to my physiology. While they may share the same rider, they are obviously very different beasts. I thought of doing a comparison between them.

For these photos, I tried to equalize the two bikes while trying to prop them up vertically. Using the Vitesse’s kickstand will lean it over to the non-drive side, while using the Minoura DS-30AL will result in the rear wheel being suspended at different heights off the ground. Both are deployed in the photos, but aren’t really used to bear the weight of either bike. I leaned the Vitesse against a wall using its handlebar grips, while I propped the TCX’s left pedal on a little stool.

One of the fundamental differences between them is in the cranks. Hyro has 170 mm crank arms, while Bino has slightly longer 172.5 mm crank arms.

Compensating for the extra 2.5 mm of length requires a correspondingly lower saddle height on the Dahon. As most experienced cyclists will tell you, saddle height is the most fundamental bike fit measurement, the one which everything else is based around. The bikes aren’t worlds apart, though, and it’s not easy to tell the difference at first glance.

Moving to the front, we look at the handlebar heights.

I ride with Bino’s stock telescoping handlepost slammed at the very bottom of its travel. Even then, Hyro’s drop handlebars are at least 3 cm lower.

Top-down view of both bikes with saddles’ rears aligned. Note the Vitesse’s seat tube, which is actually behind the bottom bracket shell.

Combining the saddle height and handlebar height, we have the reach, which is very different on both bikes. Even without factoring in the TCX’s drop handlebars, the Vitesse is the more upright bike with a much shorter reach, mainly because of the lack of a proper stem.

And no, the handlepost doesn’t really count, unless you refer to it as a super-short stem. There’s a slight 10-degree forward bend where the Dahon handlepost clamps around the steerer tube, and incidentally where its folding hinge and latch are, so it’s not quite a “zero-centimeter” stem. Turning the 580 mm handlebars on the Vitesse gives quick direction changes – which may feel twitchy to riders not accustomed.

Aftermarket “stems” are available for folding bikes to further adjust the fit. These are basically pairs of handlebar clamps connected with a cross bar which is held by the handlepost’s clamp.

By comparison, the TCX has a 90 mm stem clamped around the steerer tube, plus 70 mm of reach on the drop bars – both of which work to give a more stretched-out riding position and slow down the steering. Despite the much narrower 400 mm handlebars, cornering with the TCX is done more by leaning in with the hips than turning the bars.

This was an interesting look at how different these bikes are. Yet, it also provides an insight as to how close Dahon’s small-wheeled folding bikes are to a full-size bike’s geometry.

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