HarleyMotorcyclePartsTri Glide Ultra (FLHTCUTG): Rear Shock Work on a Solid-Axle Trike
The usual two-wheel procedure stops applying here. A differential, a body and a lot of weight change how you support and reach everything.
Any Touring shock guide you find will open by telling you to put the bike on a motorcycle lift and pull the saddlebags. Forget both. The Tri Glide stands on three wheels with a solid-axle differential and coil-over shocks each side, a rear body in the way, and far more weight over the back. The two-wheel procedure does not apply, so read this as an overview, with the trike manual setting the order.
Tools
- Trike-specific service manual
- Support equipment that the manual approves
- Wheel chocks
- Blankets and tape for body panels
- Sockets, wrenches and torque wrench
- Helper
- Tape measure
What is actually different
A two-wheeled Touring bike has a swingarm with air or emulsion shocks. Here, the back end is a solid axle carrying a differential, held up by a coil-over each side. The whole assembly behaves differently, and a two-wheel shock is not something to assume will fit. Buy parts listed for this trike, in your model year.
It also means no leaning at all. The machine does not tip onto a stand, and all that bodywork sits where a bagger would have an open view of its shocks. You cannot reason your way through this by analogy with a dresser.
Before you commit
Read the trike's service manual start to finish on this subject. Note the sequence, the support method it specifies, the body panels it wants removed, and all the torque values for the coil-over mounts. Those figures are not to be taken from any two-wheel source.
Ask whether your garage suits the work. You need a level, hard floor, room to walk around three wheels, and a place for removed panels to rest unharmed. If your support method is in doubt, it is a dealer job.
Be honest about your help, too. Moving body panels and managing supports are two-person tasks on this machine, and a lone mechanic has no one to warn them when something shifts. Line up that person before starting, and walk them through the plan.
Holding up a machine like this
A motorcycle lift is not the right tool for this vehicle. It was designed around a narrow two-wheeler, and the Tri Glide is neither narrow nor light at the rear.
Support the machine by the means and at the points your manual calls for, on equipment rated well beyond what the trike weighs. Chock whichever wheels stay on the ground. Consider what happens to the axle once a shock is released: it must be held so that it cannot drop or swing, and the manual's instructions on this come ahead of anything you read here.
Never have your body beneath this machine with only a single jack holding it.
Getting at the coil-overs
Rear body panels may need to come off. Tape the edges next to any panel you are removing, disconnect any lighting wired into it per the manual, and label each plug. Store panels on blankets, face up, out of the way. The Tour-Pak and passenger seat area may need consideration as well, so empty them and lighten what you can.
Photograph the coil-over in place from more than one angle before touching it. Note which way up it goes and how any washers and spacers are stacked.
Removal, inspection and fitting
Follow the manual's order, whether or not it agrees with your instinct from two-wheel work. Have your axle support set before anything is loosened.
A coil-over carries a compressed spring. Unbolting the assembly from the trike is one thing, but pulling that spring off the shock body is another; do not take one apart without the correct compressor and instructions.
With the unit out, check every mount. Inspect bushings for splits or looseness, the axle-side and frame-side brackets for cracks or ovaling, and threads for damage. All this extra rear weight works those points hard. Wipe everything clean so that you can see the condition rather than guess at it.
Offer up the new coil-over the way the manual shows, adjusting your support as it directs in order to align the holes. Start threads by hand. Tighten each fastener to the trike figure in the manual and mark it. If the manual says to torque with the suspension at a specified position, do it exactly that way.
Reassembly and a cautious first ride
Rebuild in reverse, restoring panels and lighting. Test all lights before the road. With the trike back on all three wheels, look at how it sits from behind; it should sit level from side to side.
Take your first ride slowly in an empty lot. A trike steers instead of leaning, and any change at the rear shows through the bars. Listen for knocks from the axle area. Check for contact between body and tires over a speed bump. Return, recheck each mount with the wrench, and inspect again following a longer run.
Mistakes that cost money
- Following a two-wheel Touring shock guide.
- Using a motorcycle lift because it is what you own.
- Assuming a dresser shock will fit a trike.
- Releasing a coil-over before the axle is supported.
- Taking a coil-over apart without a spring compressor.
When to stop
If you cannot confirm the support method from the trike manual, do not begin. An axle and body of this weight dropping unexpectedly can cause serious injury. This is a good job to hand to a dealer.
Other Harley how-to guides
This guide covers procedure and judgement. Torque figures, fluid capacities, gaps and tension settings are specific to your model and year and must come from the factory service manual for your motorcycle — we deliberately do not print numbers we cannot stand behind for your bike. Independent aftermarket retailer, not affiliated with Harley-Davidson, Inc.