A Few Thoughts on Geometry and Weight Distribution

Bryant Fork

[As a follow-up to yesterday’s post on rack stiffness, here are a few thoughts on geometry and weight distribution. —ed.]

Like so many production bikes on the market, my commuter has high trail geometry optimized for carrying a rear load (more on trail here). The assumption seems to be that a person will throw a rack and a pair of panniers on the back and call it good, which is probably true in most cases. Up to a point, my Civia handles well when loaded in this way, with the steering livening up as some weight is placed on the rear. But beyond a certain amount of weight, the front end starts feeling a little light and squirrelly, an issue that may be exacerbated by the fact that the internal gear hub also shifts the weight bias rearward.

To provide greater carrying capacity, while also mitigating for the unbalanced feeling of overloading the rear of the bike, I run a Pass & Stow porteur rack and Freight Baggage bag on the front fork. This is the rack/bag combo I’ve been running on various bikes for the past couple of years. With this set-up I’m able to balance large loads between the front and rear of the bike. Though carrying weight on the front slows down the steering and increases wheel flop, the bike feels more steady and planted on the road when cargo is split fore-and-aft in this way.

Very few production bikes have low trail geometry optimized for carrying a front load. But, in my experience, for commuting and utility riding where trips are not often more than 15-20 miles tops, front loading a high trail bike is not as much of an issue as it is for randonneuring or touring where trips can be hundreds of miles at a stretch, sometimes when the rider is tired and sleep-deprived. In other words, for short hops and city riding, I’ve had little issue with porteur racks on high trail bikes, particularly when the racks are stiff and the loads are carefully balanced between the front and rear of the bike.

 
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