Triumph Rocket III

Nowt delivers sensations like a Rocket. Here’s how to get the humungous triple and avoid any equally sizeable issues...

NOT SUCH A BRIGHT SPARK

Rocket IIIS are pretty solid overall. But problematic electrical components can be an issue regardless of the bike’s age. Reg/rec failure is common on first-generation Rockets (2004-’09); a draining battery, dimming lights and eventual failure to start/run are tell-tale signs. Early models are also susceptible to ignition coils breaking – misfires and/or loss of a cylinder(s) are signs a coil is on its last legs. Another potential problem is ignition barrel failure; the contacts at the base of the barrel crack and eventually fail, meaning the barrel won’t turn on or off. Or both. The most expensive electrical gremlin affects the current Rocket 3 (2020-onwards) and is TFT dash failure. Owners reported dicky behaviour from the ECU too; again, not a cheap fix.

DON’T GET SHAFTED

Cast a beady eye over the shaft final drive, where it connects to the back of the gearbox, particularly on early models. The seal between the two faces has a reputation for premature failure. If it’s on the way out, signs of oil leakage will be present; a puddle on the floor underneath the shaft is a sure sign it’s goosed. Fixing the seal isn’t a simple whip out and repair job. There’s a bearing in there too, and that requires a specialist press to push into place, so expect it to be a workshop fix and priced accordingly. Triumph did recall Rocket IIIS for this issue, but it’s possible bikes slipped through the net – ask your Triumph dealer to check the records if in doubt.

ALL THE GEARS

Get a test ride – several potential problems are gearbox related, so won’t make themselves known until you go for a spin. There’s an awful lot of torque pulsing through a Rocket’s transmission and sizable 240-section rear boot – a hefty 140 lb.ft on early models, rising to 146 lb.ft for later bikes – so damage to gear teeth, engagement dogs and selector mechanisms is a real possibility, particularly if a previous owner has ridden hard from cold and changed with a club foot. False neutrals, hard-to-select middle ratios, and gears jumping out under load are all signs of a problem(s), according to owners. Output shaft bearings have been known to cry enough as well – you’ll feel play in the selector mechanism, as well as vibration if there’s an issue.

If the seal’s also gone, oil will leak.

STOP – CHECK THE REAR MASTER CYLINDER

More than 3500 Rocket 3s (2020 onwards) were recalled in the US due to spongy rear brakes – not what you want on a 320kg behemoth. The issue was caused by the standard 12.7mm master cylinder being unable to move the required volume of fluid to produce maximum stopping power. The system was also subject to air ingress, exacerbating the issue. Triumph fitted a larger 14mm master cylinder to reinstate the required braking performance. If you’re looking at a bike imported from the US, check it was party to recall. Some UK bikes were recalled in 2020 after ABS modulators were found to be retaining small amounts of air, reducing performance.

ROCKET III OR ROCKET 3?

The Rocket III was launched in 2004 and appeared in several guises, before being completely redesigned as the Rocket 3 in 2020. The original model, designed to muscle in on the American market, packs a 2294cc motor making 120bhp and 140 lb.ft (tested) and is a muscle-cruiser. Two years later the Rocket III Classic was introduced, complete with footboards, pulled-back ’bars and funkier pipes. Triumph heavily reworked the Rocket III for 2009 – including new chassis, retuned motor, fairing and panniers – to create the Touring. Last of the originals is the 2010 Roadster, a pure muscle bike with ABS, sportier ergonomics and even more oomph (146bhp and 163 lb.ft). The 2020-on bike is totally different and almost like a pumped-up supernaked. 2458cc takes performance to 145bhp (tested), with handling and composure at odds with its cartoon appearance.

SHAKE, RATTLE AND ROLL

Many owners refer to Rocket IIIS making a ‘rattle spray can’ sound, particularly when cold. It’s a metallic tick-tick-tick noise, not dissimilar to when an aerosol is shaken – hence the term – which has driven many owners to distraction hunting for its cause. Cam chain slack, top-end clatter, and loose bolts have all come in for suspicion but the consensus for the click’s origin now seems to be the oil pump drive. The sound goes away, or at least subsides, when the engine’s warm. The good news is it doesn’t affect performance or running in any way, it’s simply part of Rocket III ownership – so don’t be alarmed if you hear it when inspecting a potential purchase.

‘Rocket IIIS are pretty solid, but electrical components can be problematic’