Drag the drawing to tilt it · double-click resets · scale 1 px = 1 mm on the exploded shock · tap or hover a row ↔ its balloon · silhouettes are geometry presets; jobs data stays on the Fuel EX until more recipes land.
Everything this conversion needs
Pick a drivetrain, pick a shock — the parts list, drawing and spring target all follow. Balloon numbers match the drawing.
Drivetrain — three ways to power it
| — | Mid-drive | Rear hub | Front hub |
|---|---|---|---|
| On this frame | ✓ recommended | △ compromised | ✗ discouraged |
| Torque at wheel | 120 Nm via gears | ~45 Nm direct | ~40 Nm direct |
| Climbs at 100 kg | strong — uses cassette | modest, heat on long climbs | weak + traction loss |
| Suspension effect | sprung mass — shock carries it | +4.2 kg unsprung — rear "pogos", damping fights it | +3.5 kg unsprung on the fork |
| Wear & risk | chain wear, gear-shift shock | dropout torque — arm required | fork dropout failure risk — arms both sides |
| Spring target | 624 lb/in | ≈577 est | ≈577 est |
Rear suspension — pick the shock, list updates
| Part — and where it attaches | ≈ AUD |
|---|
aff = tracked link — retailer pays the commission, your price is unchanged.
Before you order — pivot health check
13-year-old frame + ebike loads: run this first. One failure → rebuild with kits ⑧ before the build.
- Remove the shock — upper axle M10 · 10 Nm, lower bolt M8 · 85 in-lb.Fail: bolts seized or rounded.
- Cycle the bare rear triangle through full travel by hand.Fail: grinding, binding, notchy spots.
- Hold the frame, push/pull the rear wheel laterally.Fail: clunk or visible play.
- Lift by the saddle, rock it, bounce the pedals.Fail: creaks or dry squeaks.
No rear shock on this frame
The selected silhouette (hardtail / road) has nothing to check here — showing you a shock verdict would be wrong numbers, not help. Switch the silhouette back to Full-sus 26″ to use this job.
Check a part before you pay
Every dimension the engine checks, against this frame. Switch the part — the whole matrix and the drawing update.
| Check | Frame needs | This part | Verdict |
|---|
Bring calipers to the seller
Confirm these three on the physical part — listings lie, stamps don't.
- Eye-to-eye, fully extended: should tape to 184 mm (7.25 in).
- Body diameter at the fattest point: caliper ≤ ⌀42 mm.
- Size stamp on the body or air can: look for 7.25 × 2.0 — walk if it reads metric (210×50, 216×63…).
Jargon: eyelet · clevis · piggyback · eye-to-eye
No rear shock on this frame
The selected silhouette (hardtail / road) has no rear shock to replace. Switch the silhouette back to Full-sus 26″ to use this job.
Replace the worn stock shock
The stock Monarch RT3 is 13 years old. These four are the documented fits — compared in full, nothing behind a click. Pick one to preview it on the drawing.
★ Our pick — RockShox Super Deluxe Ultimate the sweet spot: modern damper, fits with the AUD 85 kit
| — | Float X2 | Super Deluxe | Bomber Air | Monarch RT3 |
|---|---|---|---|---|
| Verdict | ✓ fits w/ kit | ✓ fits w/ kit | ✓ fits w/ kit | △ −12 % travel |
| Price ≈ | AUD 950 | AUD 700 | AUD 475 | AUD 200 |
| Size | 184.2 × 50.8 | 184.2 × 50.8 | 184.2 × 50.8 | 184.2 × 44.5 |
| Damper | 4-way adj | 3-way adj | 2-way, simple | 3-position |
| Needs kit | AUD 85 | AUD 85 | AUD 85 | drop-in |
| Character | the full upgrade | the sweet spot | budget workhorse | stopgap only |
| Where | eBay AU affPinkbike no comm | eBay AU aff | eBay AU affShockcraft kit direct | eBay AU aff |
aff = tracked link. Imperial 7.25×2.0 is discontinued at AU retail — the honest sources are eBay AU (commission) and Pinkbike (none).
Install — 20 minutes, two bolts
Torques from the Trek service PDF for this exact frame.
- Deflate the old shock fully, then remove lower bolt M8 · 85 in-lb and upper axle M10 · 10 Nm.
- Press the kit reducers into the new shock's eyes — 39.9 × M10 upper, 39.9 × M8 lower.
- Seat the shock, hand-thread both bolts, then torque lower 85 in-lb, upper 10 Nm.
- Cycle full travel slowly with the air out — check nothing touches the frame.
- Set sag to 30 % (15.2 mm of the 50.8 stroke) at riding weight.
- While it's apart: run the 4-step pivot health check (see Job 1) — bearings are 427337 + 427344 if it fails.