Welcome to our Triumph spark plug finder. We’ve listed the standard plug replacement and the iridium upgrade. Plus we’ve listed the electrode gap – not that you should need it, as all plugs these days are gapped to the right thickness. However, if you want to check yours, you now have the right gap to refer to!
Iridium plugs are more expensive but they’ll last at least twice if not three times as long as conventional plugs. Use the navigation below to jump to the section you need.
Table of Contents
Triumph Spark Plug Fitment Chart
Manufacturer | Model | Standard Plug | Iridium Plug | Electrode Gap |
---|---|---|---|---|
TRIUMPH | ADVENTURER 900 | NGK DPR8EA-9 | NGK DPR8EIX-9 | 0.9 MM |
TRIUMPH | AMERICA | NGK DPR8EA-9 | NGK DPR8EIX-9 | 0.9 MM |
TRIUMPH | AMERICA / LT | NGK DPR8EA-9 | NGK DPR8EIX-9 | 0.9 MM |
TRIUMPH | BONNEVILLE | NGK DPR8EA-9 | NGK DPR8EIX-9 | 0.9 MM |
TRIUMPH | BONNEVILLE | NGK DPR8EA-9 | NGK DPR8EIX-9 | 0.9 MM |
TRIUMPH | BONNEVILLE / SE | NGK DPR8EA-9 | NGK DPR8EIX-9 | 0.9 MM |
TRIUMPH | BONNEVILLE 650 | NGK B8ES | NGK BR8EIX | 0.5 MM |
TRIUMPH | BONNEVILLE 750 (T140)/TIGER 750 (TR7V) | NGK B6ES (T140E / D) | NGK B8ES (140V / TR) | 0.5 MM |
TRIUMPH | BONNEVILLE BOBBER (EURO 4) | NGK LMAR8A-9 | 0.9 MM | |
TRIUMPH | BONNEVILLE BOBBER BLACK | LMAR8A-9 | 0.9 MM | |
TRIUMPH | BONNEVILLE SPEEDMASTER | LMAR8A-9 | 0.9 MM | |
TRIUMPH | BONNEVILLE T100 | NGK DPR8EA-9 | NGK DPR8EIX-9 | 0.9 MM |
TRIUMPH | BONNEVILLE T100 | NGK DPR8EA-9 | NGK DPR8EIX-9 | 0.9 MM |
TRIUMPH | BONNEVILLE T100 / BLACK | NGK LMAR8A-9 | 0.9-1.0 MM | |
TRIUMPH | BONNEVILLE T100 / T214 | NGK DPR8EA-9 | NGK DPR8EIX-9 | 0.8-0.9 MM |
TRIUMPH | BONNEVILLE T120 (EURO 4) | NGK LMAR8A-9 | ||
TRIUMPH | DAYTONA 1000 | NGK DPR8EA-9 | NGK DPR8EIX-9 | 0.9 MM |
TRIUMPH | DAYTONA 1200 | NGK DPR8EA-9 | NGK DPR8EIX-9 | 0.9 MM |
TRIUMPH | DAYTONA 600 | NGK CR9EK | NGK CR9EIX | 0.7 MM |
TRIUMPH | DAYTONA 650 | NGK CR9EK | NGK CR9EIX | 0.7 MM |
TRIUMPH | DAYTONA 675 | NGK CR9EK | NGK CR9EIX | 0.7 MM |
TRIUMPH | DAYTONA 675 | NGK CR9EK | NGK CR9EIX | 0.7 MM |
TRIUMPH | DAYTONA 675 | NGK CR9EIA-9 | 0.9 MM | |
TRIUMPH | DAYTONA 675 R | NGK CR9EK | NGK CR9EIX | 0.7 MM |
TRIUMPH | DAYTONA 675 R | NGK CR9EIA-9 | 0.9 MM | |
TRIUMPH | DAYTONA 750 | NGK DPR8EA-9 | NGK DPR8EIX-9 | 0.9 MM |
TRIUMPH | DAYTONA 900 | NGK DPR8EA-9 | NGK DPR8EIX-9 | 0.9 MM |
TRIUMPH | DAYTONA 955I | NGK DPR8EA-9 | NGK DPR8EIX-9 | 0.9 MM |
TRIUMPH | DAYTONA 955I | NGK CR9EK | NGK CR9EIX | 0.6 MM |
TRIUMPH | DAYTONA 955I T595 | NGK DPR8EA-9 | NGK DPR8EIX-9 | 0.9 MM |
TRIUMPH | DAYTONA SUPER III | NGK DPR8EA-9 | NGK DPR8EIX-9 | 0.9 MM |
TRIUMPH | LEGEND TT | NGK DPR9EA-9 | NGK DPR9EIX-9 | 0.9 MM |
TRIUMPH | ROCKET 3 | NGK DPR8EA-9 | NGK DPR8EIX-9 | 0.9 MM |
TRIUMPH | ROCKET 3 CLASSIC | NGK DPR8EA-9 | NGK DPR8EIX-9 | 0.9 MM |
TRIUMPH | ROCKET 3 GT (EURO 5) | NGK LMAR8A-9 | ||
TRIUMPH | ROCKET 3 R (EURO 5) | NGK LMAR8A-9 | ||
TRIUMPH | ROCKET 3 ROADSTER | NGK DPR8EA-9 | NGK DPR8EIX-9 | 0.9 MM |
TRIUMPH | ROCKET 3 TFC | |||
TRIUMPH | ROCKET 3 TOURING | NGK DPR8EA-9 | NGK DPR8EIX-9 | 0.9 MM |
TRIUMPH | SCRAMBLER | NGK DPR8EA-9 | NGK DPR8EIX-9 | 0.9 MM |
TRIUMPH | SCRAMBLER | NGK DPR8EA-9 | NGK DPR8EIX-9 | 0.9 MM |
TRIUMPH | SCRAMBLER 1200 XC | NGK LMAR8A-9 | 0.9-1.0 MM | |
TRIUMPH | SCRAMBLER 1200 XE | NGK LMAR8A-9 | 0.9-1.0 MM | |
TRIUMPH | SPEED FOUR | NGK CR9EK | NGK CR9EIX | 0.7 MM |
TRIUMPH | SPEED TRIPLE | NGK DPR8EA-9 | NGK DPR8EIX-9 | 0.9 MM |
TRIUMPH | SPEED TRIPLE | NGK DPR8EA-9 | NGK DPR8EIX-9 | 0.9 MM |
TRIUMPH | SPEED TRIPLE | NGK CR8EK | NGK CR8EIX | 0.7 MM |
TRIUMPH | SPEED TRIPLE | NGK CR9EK | NGK CR9EIX | 0.6 MM |
TRIUMPH | SPEED TRIPLE | NGK CR8EK | NGK CR8EIX | 0.7 MM |
TRIUMPH | SPEED TRIPLE 1050 | NGK CR8EK | NGK CR8EIX | 0.7 MM |
TRIUMPH | SPEED TRIPLE R | NGK CR8EK | 0.7 MM | |
TRIUMPH | SPEED TRIPLE R | NGK CR8EK | NGK CR8EIX | 0.7 MM |
TRIUMPH | SPEED TRIPLE RS | NGK CR9EIA-9 | 0.8-0.9 MM | |
TRIUMPH | SPEED TRIPLE S | NGK CR8EK | 0.7 MM | |
TRIUMPH | SPEED TRIPLE S | NGK CR9EIA-9 | 0.8-0.9 MM | |
TRIUMPH | SPEED TRIPLE T509 | NGK DPR8EA-9 | NGK DPR8EIX-9 | 0.9 MM |
TRIUMPH | SPEED TWIN | NGK LMAR8A-9 | 0.9-1.0 MM | |
TRIUMPH | SPEEDMASTER | NGK DPR8EA-9 | NGK DPR8EIX-9 | 0.9 MM |
TRIUMPH | SPEEDMASTER | NGK DPR8EA-9 | NGK DPR8EIX-9 | 0.9 MM |
TRIUMPH | SPEEDMASTER | NGK DPR8EA-9 | NGK DPR8EIX-9 | 0.9 MM |
TRIUMPH | SPEEDMASTER | NGK DPR8EA-9 | NGK DPR8EIX-9 | 0.9 MM |
TRIUMPH | SPRINT 900 | NGK DPR8EA-9 | NGK DPR8EIX-9 | 0.9 MM |
TRIUMPH | SPRINT 900 | NGK DPR8EA-9 | NGK DPR8EIX-9 | 0.9 MM |
TRIUMPH | SPRINT GT | NGK CR8EK | NGK CR8EIX | 0.7 MM |
TRIUMPH | SPRINT RS | NGK DPR8EA-9 | NGK DPR8EIX-9 | 0.9 MM |
TRIUMPH | SPRINT RS | NGK CR9EK | NGK CR9EIX | 0.6 MM |
TRIUMPH | SPRINT ST | NGK DPR8EA-9 (-00) | NGK CR9EK (01-) | 0.9MM / 0.6MM |
TRIUMPH | SPRINT ST 1050 | NGK CR8EK | NGK CR8EIX | 0.7 MM |
TRIUMPH | STREET CUP (EURO 4) | NGK LMAR8A-9 | 0.9-1.0 MM | |
TRIUMPH | STREET SCRAMBLER | NGK LMAR8A-9 | 0.8-0.9 MM | |
TRIUMPH | STREET SCRAMBLER (EURO 4) | NGK LMAR8A-9 | 0.9-1.0 MM | |
TRIUMPH | STREET TRIPLE | NGK CR9EK | NGK CR9EIX | 0.7 MM |
TRIUMPH | STREET TRIPLE | NGK CR9EK | NGK CR9EIX | 0.7 MM |
TRIUMPH | STREET TRIPLE | NGK CR9EK | NGK CR9EIX | 0.7 MM |
TRIUMPH | STREET TRIPLE R | NGK CR9EK | NGK CR9EIX | 0.7 MM |
TRIUMPH | STREET TRIPLE R | NGK CR9EK | NGK CR9EIX | 0.7 MM |
TRIUMPH | STREET TRIPLE R | NGK CR9EK | NGK CR9EIX | 0.7 MM |
TRIUMPH | STREET TRIPLE R (EURO 4) | NGK CR9EIA-9 | 0.9 MM | |
TRIUMPH | STREET TRIPLE RS (EURO 4) | NGK CR9EIA-9 | 0.9 MM | |
TRIUMPH | STREET TRIPLE RS (EURO 5) | |||
TRIUMPH | STREET TRIPLE RX | |||
TRIUMPH | STREET TRIPLE S (EURO 4) | NGK CR9EIA-9 | 0.9 MM | |
TRIUMPH | STREET TRIPLE S A2 (EURO 4) | NGK CR9EIA-9 | 0.9 MM | |
TRIUMPH | STREET TWIN | NGK LMAR8A-9 | 0.9-1.0 MM | |
TRIUMPH | STREET TWIN | NGK LMAR8A-9 | 0.8-0.9 MM | |
TRIUMPH | THRUXTON | NGK DPR8EA-9 | NGK DPR8EIX-9 | 0.9 MM |
TRIUMPH | THRUXTON | NGK DPR8EA-9 | NGK DPR8EIX-9 | 0.9 MM |
TRIUMPH | THRUXTON 1200 (EURO 4) | NGK LMAR8A-9 | 0.9-1.0 MM | |
TRIUMPH | THRUXTON R 1200 (EURO 4) | NGK LMAR8A-9 | 0.9-1.0 MM | |
TRIUMPH | THRUXTON RS (EURO 5) | NGK LMAR8A-9 | ||
TRIUMPH | THUNDERBIRD | NGK DPR8EA-9 | NGK DPR8EIX-9 | 0.9 MM |
TRIUMPH | THUNDERBIRD 1600 | NGK DPR6EA-9 | – | 0.9 MM |
TRIUMPH | THUNDERBIRD 1600 | NGK DPR6EA-9 | – | 0.9 MM |
TRIUMPH | THUNDERBIRD SPORT | NGK DPR8EA-9 | NGK DPR8EIX-9 | 0.9 MM |
TRIUMPH | THUNDERBIRD STORM / COMMANDER / LT | NGK DPR6EA-9 | 0.9 MM | |
TRIUMPH | TIGER 1050 SPORT | NGK CR8EK | NGK CR8EIX | 0.7 MM |
TRIUMPH | TIGER 1050 SPORT (EURO 4) | NGK CR8EK | NGK CR8EIX | 0.7 MM |
TRIUMPH | TIGER 1050 / SE | NGK CR8EK | NGK CR8EIX | 0.7 MM |
TRIUMPH | TIGER 1200 EXPLORER | NGK CR8EK | NGK CR8EIX | 0.7 MM |
TRIUMPH | TIGER 1200 EXPLORER XC | NGK CR8EK | NGK CR8EIX | 0.7 MM |
TRIUMPH | TIGER 1200 XC. XCX / LOW. XCA (EURO 4) | NGK CR8EK | 0.7 MM | |
TRIUMPH | TIGER 1200 XCX / LOW. XCA | NGK CR8EK | ||
TRIUMPH | TIGER 1200 XR. XRX / LOW. XRT | |||
TRIUMPH | TIGER 1200 XR. XRX / LOW. XRT (EURO 4) | NGK CR8EK | 0.7 MM | |
TRIUMPH | TIGER 800 | NGK CR9EK | NGK CR9EIX | 0.7 MM |
TRIUMPH | TIGER 800 XC (CROSS COUNTRY) | NGK CR9EK | NGK CR9EIX | 0.7 MM |
TRIUMPH | TIGER 800 XC. XCX / LOW. XCA (EURO 4) | NGK CR9EK | 0.7 MM | |
TRIUMPH | TIGER 800 XC / XCX / XCA | NGK CR9EK | 0.7 MM | |
TRIUMPH | TIGER 800 XCX. XCA | NGK CR9EK | NGK CR9EIX | 0.7 MM |
TRIUMPH | TIGER 800 XR. XRX. XRX LOW. XRT | NGK CR9EK | NGK CR9EIX | 0.7 MM |
TRIUMPH | TIGER 800 XR. XRX / LOW. XRT (EURO 4) | NGK CR9EK | 0.7 MM | |
TRIUMPH | TIGER 800 XR / XRX / XRT | NGK CR9EK | 0.7 MM | |
TRIUMPH | TIGER 900 | NGK DPR8EA-9 | NGK DPR8EIX-9 | 0.9 MM |
TRIUMPH | TIGER 900 | NGK DPR8EA-9 | NGK DPR8EIX-9 | 0.9 MM |
TRIUMPH | TIGER 900 (EURO 5) | |||
TRIUMPH | TIGER 900 GT / LOW (EURO 5) | |||
TRIUMPH | TIGER 900 GT PRO (EURO 5) | |||
TRIUMPH | TIGER 900 RALLY (EURO 5) | |||
TRIUMPH | TIGER 900 RALLY PRO (EURO 5) | |||
TRIUMPH | TIGER 955I | NGK DPR8EA-9 | NGK DPR8EIX-9 | 0.9 MM |
TRIUMPH | TIGER 955I | NGK DPR8EA-9 | NGK DPR8EIX-9 | 0.9 MM |
TRIUMPH | TIGER 955I | NGK DPR8EA-9 | NGK DPR8EIX-9 | 0.9 MM |
TRIUMPH | TRIDENT 750 | NGK DPR8EA-9 | NGK DPR8EIX-9 | 0.9 MM |
TRIUMPH | TRIDENT 900 | NGK DPR9EA-9 | NGK DPR9EIX-9 | 0.9 MM |
TRIUMPH | TROPHY / SE | NGK CR8EK | NGK CR8EIX | 0.7 MM |
TRIUMPH | TROPHY 1200 | NGK DPR8EA-9 | NGK DPR8EIX-9 | 0.9 MM |
TRIUMPH | TROPHY 1200 | NGK DPR8EA-9 | NGK DPR8EIX-9 | 0.9 MM |
TRIUMPH | TROPHY 900 | NGK DPR8EA-9 -’95 | NGK DPR8EIX-9 | 0.9 MM |
TRIUMPH | TROPHY / THUNDERBIRD / TIGER | NGK B8ES | NGK B7HS / B7ES | 0.5 MM |
TRIUMPH | TT 600 | NGK CR9EK | NGK CR9EIX | 0.7 MM |
Reading your spark plug
The image of the spark plugs above shows four common conditions that you’ll find your spark plugs in. From left to right the plugs are Normal, Rich, Lean and Very Lean. Full descriptions below.
Before you throw your old spark plug in the bin, check them to get an understanding of how well your engine is running.
Normal condition
If the plug is brown or light grey your can assume your engine is in good condition and the spark plug is functioning well. Even when a plug is in good condition small deposits will accumulate. This is normal.
Rich
There are many different causes of spark plug fouling. If the plug has oil on it, then it’s oiling up and may not work efficiently, potentially causing a misfire or stuttering under hard acceleration. If it’s just dark or black the bike could be running too rich. A heavy accumulation of carbon on the nose can cause a leakage path to earth. This can cause misfires and poor engine starting.
Causes: The causes of this can be anything from, a rich fuel mixture, too much choke, long periods of low-speed riding or idling in traffic, a blocked air filter or the plug’s heat range is too cold.
Lean
If the engine is running lean then the spark plug has a grey colour but you’ll probably see some black deposits on there too.
Causes: Insufficient cooling, blocked injectors, too lean a fuel mixture
Very Lean
If the engine is running dangerously lean the whole plug tip will be grey or white. If the temperature is over 850-degrees, pre-ignition may occur. Engine power will be reduced and you risk piston damage.
Causes: Insufficient cooling, blocked injectors, too lean a fuel mixture, ignition timing too far advanced, excessive combustion chamber deposits.
Motorcycle Spark Plug Fitting Guide + Tips
- When you’ve removed your spark plugs, check the condition of the threads in the cylinder head and put a cloth over the cylinder head if you’re going to leave it exposed.
- Install each spark plug by hand until you have wound the thread a couple of turns. This reduces the chances of you cross-threading the plug.
- Torque the spark plug up to your manufacturer’s recommended settings. If you don’t have a torque wrench, then get the plug hand tight and then add a ½ turn for a plug with a gasket, and more like a ¼ turn for a tapered spark plug. Over-tightening can snap the spark plug – a nightmare.
- Don’t put any lubricant or thread lock on the spark plug. Inspect your spark plug caps and replace if required.
Iridium Spark Plug vs Standard
A regular spark plug uses a copper central electrode whereas an iridium spark plug uses, you guessed it, iridium.
The metal in a spark plug has a single purpose: to channel the electrical energy through the spark plug. Iridium is far harder than copper and this allows the spark plug manufacturers to create a plug with a sharper ‘tip’ which better focuses the spark around the centre electrode without compromising its service life.
A typical copper spark plug will last around 20,000 miles and most get changed at a major service (usually around 16,000 miles) but an iridium spark plug will be good for around 50,000 miles and you do see people running them to 100,000 miles with no issues.
Copper is generally seen as being the best metal to use in terms of conductivity but iridium plugs are seen as premium as they last longer than standard plugs and can be built with smaller tolerances. Iridium spark plugs also have lower voltage requirements, meaning they perform better when starting and idling and some manufacturers also claim they offer a better throttle response.
Iridium plugs are more expensive than copper but seeing as they last longer and offer a more consistent performance throughout their lifetime, many bikes opt for an iridium ‘upgrade’.
Spark Plug Removal
If you’re going to be doing any sort of work on the bike, treat yourself to a decent set of tools. Most of mine are from the Halfords Advanced range (formerly called Professional).
They have a lifetime guarantee and for an amateur bodger like me, they’re perfect.
The image above shows their 100pc range, which costs around £125. It’s a comprehensive bit of kit and includes a 1/4″, 3/8″ and 1/2″ drive, alongside plug sockets, universal joints and a wobble bar. Pretty much everything you’ll ever need for any motorcycle maintenance job.
Motorcycle Spark Plug Removal Tools
If you’ve not changed your plugs before, give yourself a couple of hours to complete the task. Here are the essentials you need for smooth re-plugging:
Your owner’s manual
You’ll need this to help you find the location of your spark plugs and how to access them. This may sound simple but often the manual offers up some time-saving tips for your particular model.
A spark plug socket
You’ll need a deep socket. A decent tool kit will have them. Don’t get confused between thread size and socket size. Motorcycle spark plug socket sizes are usually 16mm, 18mm or 20.6mm (21mm will do). Whereas the threads are usually 10mm, 12mm or 14mm. When it comes to motorcycles, access is usually tricky, so my tip is to buy a magnetic spark plug socket like this one. Once you’ve undone your old plug, this will help you remove it with far less effing and jeffing.
A wobble socket / universal joint
You’ll be lucky if there’s a straight line to your spark plug, so a universal joint will get you the angle you need to apply some torque. Again, a decent toolset will have one.
A 3/8″ drive
You could buy a specific spark plug T-bar but your home tool kit will have the drive you need to connect to your plug sockets.
A spark plug gap gauge
This nifty little tool only costs a few quid and will help you set the correct gap for your spark plug. However, modern plugs are almost all motorcycle-specific fit and so they come ‘pre-gapped’ and you won’t need to touch them. If you’re running a classic bike, you’ll probably need to set your gap and if your bike’s not running right, a gap tool can help you rule out a potential incorrect gap issue.
A torque wrench
It’s important to properly torque your spark plugs. Too tight and you’ll risk snapping it or it will be a mission to remove. Too loose and you risk an electrical short. Your owner’s manual will have the correct torque settings.
Motorcycle Spark Plug FAQ
What are the common motorcycle spark plug sizes?
Thread diameters of 10mm, 12mm, and 14mm are the most common. In fact, when it comes to motorcycles, it's rare to find any other sizes in use.
How long should a spark plug last?
Motorcycle spark plugs usually last around 16,000 miles, or at least this is when most manufacturer service schedules recommend you change them. That's typically once every other major service. However if you use Iridium spark plugs they will last a lot longer, usually well over 30,000 miles.
How do you clean motorcycle spark plugs?
Just remove the plug and use a wire brush to gently brush off any deposits on the electrode. Don't use a power tool, by hand is all that's required.