Crank Forward Bicycle Geometry and Motors

Discussion in 'General Questions' started by Hive, Mar 25, 2011.

  1. Hive

    Hive Guest

    Some of the below is posted in the Rack Mounted thread, but I got to thinking the information might be helpful for those outside that topic.

    For marketing reasons, these bikes are somewhat scarce, although due to Rans success in marketing the bike, others tried and gave up. That is unfortunate.

    CF bikes allow riders to plant both feet flat on the ground and offer a ride similar to a recumbent, but with visibility and much easier starting.

    Here are pics of the two CFs or crank forwards. Fuji made a model, Saratoga, which I forgot to add. There are other makers who tried to market the CF which, for some reason, does not appeal to traditional bike ideal, which is silly.

    BTW, you can guesstimate seat height from ground, in the below pic. Rear wheel is 26, engine mount from axle is how many standard inches...there you have it. The Rans is near exact height. Rans is much lighter, with more conventional appearance, with its short front frame and longer steer tube.

    Look around, they can be had very cheap. Just be sure the rear wheel has 36 spokes and the drive ring-to-fork space is wide enough...

    Moreover, if you are going to ride around under power, it might be a good idea to spend a few more dollars for a sturdier, safer bike than is typically marketed in box stores.

    Point is, if you look closely, you can visualize engine placement, close to seat, and the idea that you get full power from legs but still can put both feet comfortably flat on ground.

    I do not know if the spendy Rans Dynamik ($700 used) can take the hammering of motoring and have not tried it. It is much lighter than the Raleigh and the Fuji.

    If you decide the CF is for you, add a shock fork to ease the pain at speed.

    The fork on the Gruv wobbles during turns or at speed when zigging a bit, but I know it and am careful.

    I acquired a shock fork from Vegaspaddy here and was smart move and grateful he was selling when I needed fork. That was good investment for the Rans, as it had hard front fork and the ride is much smoother, and will be so if I add engine...

    The wider frame and geometry may not be suited to engines mounted within the frame, but if one favors those engines, the CF benefits should be reviewed.


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    Last edited by a moderator: Mar 25, 2011