Brommie “Cycle Truck”

Fork-mounted “porteur” style racks are becoming increasingly popular. They’re super effective for carrying bulky items that won’t fit in a touring pannier, and when combined with a basket or cargo bag, they’re convenient as catch-alls for running errands or commuting. The downside is that carrying a load on the front fork slows down a bike’s handling, and if the load is above the front wheel, it may cause “wheel flop”. Some of this can be mitigated for with low trail geometry, but the selection of low trail production-level bikes is extremely limited.

I have two bikes with cargo racks mounted on the fork; a Civia Loring with the factory rack, and a Surly LHT with a Pass & Stow. Neither have low trail geometry, but I’ve become completely acclimated to carrying weight on the fork, so it’s not really an issue for me. On the other hand, my little Brompton has a frame-mounted carrier that takes the weight off of the fork and places it on the main frame. The difference between these two set-ups is striking. While I notice even subtle differences in how much weight I’m carrying on the Civia and Surly, the Brompton’s steering is unaffected by even relatively heavy loads. This difference may explain the growing number of so-called “cycle trucks” and their variants, with their smaller front wheels and cargo platforms mounted to the frame above the front wheel.

I don’t have much experience with “real” cycle trucks, but I hope to eventually obtain one for review; it’ll be interesting to compare its load carrying capabilities and handling to my existing bikes with fork-mounted carriers. If it ends up being anything like my little “Brommie Cycle Truck”, it should fare quite well.

5 Responses to “Brommie “Cycle Truck””

  • Spencer says:

    I echo your Brompton experience. I’ve loaded it up with a fairly creative assortment of cargo, including lawn signs for Madison’s August Ride the Drive with Lance. I have an extra bag frame that I use mostly with my Carradice bag, but strap odds and ends to it at times. It’s quite the little trooper.

  • Lovely Bicycle! says:

    How much weight do you carry on the fork-mounted systems in order to sense a difference in handling? I’ve recently installed a fork-mounted front rack on my Hillborne and have been carrying a handlebar bag on it with 15lb of weight. I got used to the bag immediately and can feel no difference in handling while cycling.

    On a related note, could you recommend a good read about high trail vs low trail geometry, or better yet, write your own post about it? Some visual examples of low vs high trail geometry bikes would be especially appreciated!

  • Alan says:

    @Lovely Bicycle!

    “How much weight do you carry on the fork-mounted systems in order to sense a difference in handling?”

    Not to imply I have some sort of heightened sensitivity, but even 5 lbs. is noticeable to me. I think after a short while most people adapt, as long as we’re not talking about large amounts of weight (say 20 lbs. or more).

    “On a related note, could you recommend a good read about high trail vs low trail geometry, or better yet, write your own post about it?

    Jan Heine of Bicycle Quarterly has probably written about, and done more to promote low trail geometry than anyone in recent years. You can order back issues on his website. You might start with Volume 4, No. 3 (Spring 2006):

    http://www.vintagebicyclepress.com/contents.html

    Jan Heine and Grant Petersen disagree on what constitutes the proper amount of trail, but have agreed to disagree:

    http://www.rivbike.com/article/bicycle_making/trail_wheelbase_etc

    David Gordon Wilson’s Bicycling Science goes into great detail on the subject:

    http://www.amazon.com/Bicycling-Science-David-Gordon-Wilson/dp/0262731541

    Here’s a pretty good intro to the subject on the Spectrum Cycles site:

    http://www.spectrum-cycles.com/612.htm

    This subject is almost, but not quite, as controversial as bicycle helmets. You’ll find strong opinions on both sides.

    “Some visual examples of low vs high trail geometry bikes would be especially appreciated!””

    Because trail is affected by head angle, fork offset, and wheel diameter, it’s not simple to see the amount of trail a bike has with a casual look. Short of having the bike on hand, you really need a clean side shot with no distortion and a graphics program (or protractor and ruler) to measure trail.

    Regards,
    Alan

  • Lovely Bicycle! says:

    Wow, thanks – will have a look at those. I have read enough second hand accounts of Heine’s and others’ views to be familiar with the debate, but never one of the original articles where the arguments were put forth. Thanks again for taking the time to make these recommendations.

  • Ralph Aichinger says:

    There is one aspect of riding a cargo bike with large front carrier, that may or may not be present on your Brompton, and that might feel strange at first (it did to me): You no longer see the front wheel, or the road directly below it, for that matter.

 
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