Products affected: Gocycle G1 and G2; all frame numbers
The Gocycle utilises a version of the Shimano 3 speed Nexus® internal hub gear driving the rear wheel. Internal hub gears like the Gocycle Shimano Nexus® require regular maintenance and checking of the bearings in order to ensure that they continue to operate correctly and safely. Proper maintenance of the Gocycle hub gear is detailed in section 7.9 of the G2 Owner’s Manual and section 9.12 in the G1 Owner’s Manual. Failure to regularly check and appropriately maintain and adjust the bearings can result in excessive play in the rear wheel or a rear “wheel wobble” to develop, which can impair satisfactory control of the Gocycle while riding and poses a risk to rider safety.
In the event that a Gocycle with an incorrectly maintained or adjusted rear wheel hub gear is ridden the following could occur: premature and/or uneven tyre wear, loss of control of the bicycle due to rear “wheel wobble” or a loose rear wheel, increased rear break rub, or unexpected and sudden failure of the rear wheel assembly during riding. All may cause loss of control of the Gocycle and pose a serious fall hazard.
Symptoms of worn bearings or bearings that are not correctly adjusted either as delivered new or after minimal riding miles or after adjustment or after high mileage riding and that require checking and re-adjustment will be a rear “wheel wobble” or a loose rear wheel or the rear disk brake rotor contacting the calliper as shown in figure 1. If the rear disk brake rotor is contacting or rubbing the rear calliper back plate as shown, you should stop ridding the Gocycle immediately and until the hub gear bearings have been adjusted correctly.
Figure 1. Example of the rotor disk contacting the rear calliper back plate.
Figure 2. Demonstration of rocking the rear wheel
The outlined symptoms should be checked after the first 100 miles and then every 500 miles or every 6 months of riding. Adjust when necessary as per below.
Remove the hub cap.
Using two 14mm flat wrenches, adjust the rear hub gear bearing cups.
Between adjustments, check that the rear hub rotates in the freewheel direction. The bearing cup nuts should be tightened until the wheel does not have more than 1mm of “free” play at the rim, and the wheel is able to rotate freely. This is a matter of compromise and feel. If in doubt, consult Gocycle Tech Support for advice.
Retighten the outer lock nut. Note: after tightening the outer lock nut, the hub may need re-adjusting due to the nature of the tightening process. You may need to repeat this process until you have the desired freeness of rotation and minimal lateral play at the rim.
Can I Continue to Ride my Gocycle?
After completing the checks outlined above and completing any appropriate adjustment, you can ride the Gocycle in accordance with its normal intended usage.