Originally Posted by
twocicle
Roll the dice and take a chance.
Caveats:
Just about every legit E-Bike out there from singles onward, are overbuilt to some degree in order to deal with the extra loads put on most all components of the e-bike.
A carbon rim brake fork is obviously not designed to withstand much hub torque, let alone pulling +300lbs of team mass and the increased "Euro" motor torque model exasperates the issue.
Food for thought: Perhaps revisit the forum posts last year showing photos of the sad couple who tacoed their flimsy front wheel when hitting a pothole on a fast downhill.
PS: Please add me to your list of estate recipients.
I suppose any wheel, even a car wheel, when hitting a deep pothole at speed will be tacoed or severely damaged.
The Cytronex is specified for tandem use and ours seems considerably more substantial than the Spinergy it replaces.
I'm not an engineer, but I'm afraid I don't follow your logic regarding hub torque affecting the fork. Surely the torque is applied to the wheel itself and the only way torque would be associated with the fork is if the wheel is not tightly installed and it "rolls" out of the dropouts. Overall weight and speed on braking would affect the fork of course, but the additional weight of motor+battery is only about 8 lb. In our case, tandem + team=370 lb, so it's only an additional 2% . The motor would not be "on" while braking, so no force from that. We have ridden about 500 miles with the system, admittedly with no hill challenges, only wind, but we are very impressed by ease of ordering, customer support, ease of installation (30 minutes) and performance. The Georgia Tandem Rally next month will give it a real test. More then....