Noob question - GEBE on a Catrike

Discussion in 'Motorized Recumbents' started by jec, Mar 12, 2012.

  1. jec

    jec New Member

    For almost a year now, I've had a GEBE system on this upright bike:
    [​IMG]
    No problems whatsoever; it's been great. I got curious over the weekend, and swapped the rear tire from this bike, and the GEBE system, onto my Catrike Expedition (no photos at the moment, sorry). The only difficulty was making a mount/connection point for the engine support strap to secure to the frame, but that didn't take too much time and headache. FYI, unlike a two-wheel recumbent, I didn't need a longer throttle cable, because the cable snaked down the side of the seat frame and looped up at the handlebar just the same as the shifter cable does.

    My question is more bike oriented than GEBE/motor oriented. I swapped in the upright bike wheel because: the wheel and tire (and to my untrained eye, perhaps the spokes) from the upright are fatter/beefier than the Catrike wheel and tire (the swapped-in wheel/tire width is 1.60, maybe 1.75 if IIRC); even though the upright bike gearset is seven speed to the Catrike's nine, the one or two gears I use most with a motor seem to translate without adjusting the derailleur cable; the Catrike has a quick release wheel, so no go on the GEBE; and, I already had the GEBE drivering installed on the upright wheel.

    All seems to fit well, wheel rolls true, lots more clearance on the Catrike for wheel and drivering than the fraction of an inch it had on the upright. Just as on the upright, it seemed to work fine. No problems on a 10 or more mile ride. So, my noob question on the wheel: am I risking any sort of catastrophic failure or other big problem just by swapping wheel to wheel? To explain a bit more, is there some important aspect, measurement, or other engineering-type issue I don't know about when swapping wheels that could/will lead to a problem, or is the answer simple - any problem will be immediately apparent, and if it fits and works, it should work long term? As I mentioned, the swap went smoothly and the motorized Catrike seemed to run like a top.

    FYI, the GEBE on the Catrike also runs 7-10 mph faster, by a rough estimation. The upright topped out at 22 mph by my GPS on the flat (I got the GEBE drive gear that's for less high end, more torque - can't remember if that's more or less teeth), which was fine with me. My 14-year-old son (a beef who's bigger than me) begged to ride it, and I paced him on my motorcycle; with my speedo registering 32 mph, he was slowly pulling away (my speedo may be 2-3 mph "generous"). Whatever the exact speed, it's definitely faster on the Catrike with that reduced frontal area hitting the wind.

    A silly question perhaps, that demonstrates my meager knowledge of the mechanics of, and working on, a bicycle, but any input would be most appreciated. If I'm asking for major trouble by swapping the wheel from upright to Catrike rather than searching out a truly compatible wheel if that's necessary, I'd like to find out from you rather than from splattering myself during a ride. Many thanks.
     

  2. jec

    jec New Member

    The Expedition

    No replies, so I guess I'll keep my fingers crossed. Took the CatGEBE out tonight with the GPS, which clocked it at 29mph. It still felt like it was accelerating, but traffic and darkness prevented me from any more cruising with one hand and reading GPS with the other. I suspect some of the speed improvement is due to the position of the throttle cable; on the upright, the handgrip may have blocked the throttle lever's travel before it was wide open. Still, I think some of the improvement is the recumbent's aerodynamics. Again, if anybody can weigh in on whether swapping this rear wheel from the upright is asking for trouble, or not, I'd much appreciate it. A photo of the CatGEBE:

    [​IMG]
     
  3. lowracer

    lowracer Member

    Trike looks great!
    I dont think you'll have any problems with the rear wheel swap as long as your shifting is still crisp. Is there any way of rotating the engine strut 90 degrees to behind the trike rear tire?
    Looks as though the exhaust will blow into your face/hair when stopped at a light with a tailwind & very loud sitting directly behind your ears?
    There is a way to route the exhaust down & to the rear with some flex pipe & clamps...
    -Lowracer-
     
  4. TREEWK

    TREEWK Member

    On some of my motors a 90 degree 1/2 inch copper elbow and a short piece of 1/2 inch tubing added as needed. I slit my copper elbow and used a gas line clamp, but 2 small screw`s would work. It helped with the noise also, but Lowracer`s idea may be even more quiet.

    Ron
     
    Last edited: Mar 17, 2012
  5. ollicat

    ollicat Member

    I don't know much about your upright bike, but I also switched my GEBE system from an upright to a recumbent and gained speed. Best guess is better components with lower resistance on the bents.
     
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