Suzuki DR-Z400 and DR-Z400 SM Maintenance Schedule and Service Intervals
This is the maintenance schedule and associated service intervals for the Suzuki DR-Z400 range of motorcycles.
This maintenance schedule applies to the following models:
- Suzuki DR-Z400 — the generic name for both
- Suzuki DR-Z400E/S/SE — specifically the dual sport variant
- Suzuki DR-Z400SM — the supermoto variant.
The Suzuki DR-Z400 is a motorcycle platform that has been manufactured by Suzuki for over two decades. It’s available in dual sport form and in street bike supermoto form (the SM).
Both the dual-sport and supermoto are powered by a single-cylinder 398 cc carburettor-fed liquid-cooled four-stroke and four-valve engine, with power to the ground through a wet clutch and chain drive.
This page includes the maintenance schedule for both the supermoto and the dual sport together. They share a platform and the same maintenance components, even though there are some differences. The difference between the DR-Z400SM and the DR-Z400E is that the DRZ400SM gets:
- An inverted front fork for better suspension in street riding,
- Wide 17-inch street rims (still spoked, though) with tubeless (rather than tubed) tyres, and
- A larger 300mm diameter floating front brake rotor (still a single disc)
The DR-Z400 has remained basically the same as when it was launched 20 years ago. You can still buy it new in 2021 with a carburettor-fed engine.
See the pics below for a direct comparison between the dual-sport DR-Z400E and the supermotard DR-Z400SM. Note the wheels/tyres, front suspension, and front brake disc.
Updated 2023 with an inspection checklist, overview of service intervals, and more info for a basic service.
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Suzuki DR-Z400 Service Intervals
The Suzuki DR-Z400 has 3500 mile / 6000 km or 12-month service intervals. At every service, change the oil and do a general inspection. Change the spark plugs every 2 services.
The major valve clearance service interval on the DR-Z400 is a much wider 15000 miles or 24000 km.
As the DR-Z400 has a liquid-cooled engine, you should replace the coolant every 4 years — using Suzuki Super Long-life Coolant.
Aside from that, change the brake fluid regularly (2 years under normal use), and pay attention to the chain slack and condition.
What you need to service the Suzuki DR-Z400
If you’re servicing your DR-Z, you are in for a treat — servicing it is both easy and rewarding.
The DR-Z400’s engine is a straightforward one to service. It has a 4-valve single-cylinder engine and everything is very accessible.
| Part | Suzuki DR-Z400 spec |
|---|---|
| Engine oil | The service manual recommends SAE 10W-40 oil that meets SF or SG spec. Most motorcycle oils fit this, so use something like Motul 5100 10W-40. |
| Oil filter | Use a Hiflofiltro HF139 oil filter. |
| Spark plug | The spark plug is an NGK CR8E. |
| Air filter | You can usually clean the air filter. But if you need to replace it, the Twin-Air 153156 air filters are popular on the DR-Z. |
| Coolant | The service manual specifies Suzuki coolant, or another coolant/antifreeze suitable for aluminium radiators. Most ethylene glycol coolants with rust inhibitors are fine, e.g. Pro Honda Coolant. |
| Brake pads | The brake pads are the same on the SM and E versions despite different size discs. Use an EBC FA185R pad for the front, and FA131R for the rear. |
| Brake fluid | The manual specifies DOT 4, e.g. Castrol DOT 4. |
| Fork oil | The service manual specifies Suzuki fork oil SS-05, which is a similar weight to Bel-Ray 5W Fork Oil. |
| Chain lubricant | You can use engine oil, or Motul chain paste, which is low-mess and easy to carry. |
| Cable lubricant | You can use engine oil to lubricate cables or use Protect all cable life, a well-known lube. |
| General lube | Use lithium soap-based grease for general lubrication. |
Suzuki DR-Z400 Maintenance Schedule
Below is the maintenance schedule for the Suzuki DR-Z400 motorcycles. It’s the same between the DR-Z400E and the DR-Z400SM (same engine).
The maintenance schedule is the same as that which you see in the manual — it’s just formatted differently here so it’s easier to parse.
NOTES
- There are time-based and distance-based intervals — follow the shorter of the two.
- At the end of the service schedule, keep following it in the pattern shown.
| Months | 2 | 12 | 24 | 36 | 48 | |
|---|---|---|---|---|---|---|
| km x 1000 | 1 | 6 | 12 | 18 | 24 | |
| miles x 1000 | 0.6 | 4 | 7.5 | 11 | 15 | Every |
| Perform full standard inspection checklist (see below) | ✓ | ✓ | ✓ | ✓ | ✓ | |
| Engine oil — Replace (Motul 5100 10W-40) Tighten frame tube drain plug to 18 Nm / 13 lb-ft Tighten drain plug to 21 Nm / 15 lb-ft | ✓ | ✓ | ✓ | ✓ | ✓ | |
| Engine oil filter — Replace (HF139) | ✓ | ✓ | ||||
| Air cleaner element — Inspect | ✓ | ✓ | ✓ | |||
| Air cleaner — Replace (Twin-Air 153156) | ✓ | |||||
| Spark plug — Inspect Gap: 0.7-0.8mm / 0.028-0.031 in Replace existing plug to 1/8 turn past finger tight | ✓ | ✓ | ||||
| Spark plug — Replace (NGK CR8E) Tighten new plug to 1/2 turn past finger tight | ✓ | ✓ | ||||
| Valve clearances — Inspect / Adjust | ✓ | |||||
| Engine coolant — Replace (Suzuki Super Long Life Coolant kind — Blue, or Honda Coolant) | 4 years or 48000 km (29000 miles) | |||||
| Brake fluid — Replace (Use DOT 4 fluid only) | 2 years | |||||
| Steering — Check smooth operation without notches | ✓ | ✓ | ✓ | |||
| Exhaust pipe bolts and muffler bolts — Tighten | ✓ | ✓ | ✓ | |||
| Front fork — Check smooth operation, no damage or leaks | ✓ | ✓ | ||||
| Rear suspension — Check smooth operation, no damage or leaks | ✓ | ✓ | ||||
| PAIR (air supply) system — Inspect | ✓ | ✓ | ||||
| Evaporative emission control system (California model only) — Inspect | ✓ | ✓ | Replace hose every 4 years |
Suzuki DR-Z400 Service Checklist
Below is a service checklist for the DR-Z400. Do these checks / actions per the schedule above.
Some of these items should be done more often. These are noted first.
| Suzuki DR-Z400 Annual Service Checklist |
|---|
| Perform general lubrication of external moving parts (Lithium soap-based grease) Every 600 mi / 1000 km |
| Drive chain — Check condition, tension, and wear (see below) |
| Drive chain — Clean and lubricate (Motul chain paste) Every 600 mi / 1000 km |
| Fuel lines — Check condition, damage, routing |
| Radiator lines — Check condition |
| Spark arrester — Clean |
| Engine oil lines — inspect for damage |
| Throttle cable play — Check (2-4mm / 0.08-0-.16 in) Adjust play using the adjuster on the throttle, after loosening the locknut. |
| Idle speed — Check (1400-1600 rpm) — Requires tachometer or automotive multimeter After engine is warm, turn throttle stop screw on carburettor to reach target rpm |
| Clutch — Check free play (10-15mm / 0.14-0.16 in) and adjust if necessary. Lubricate cable (Protect All Cable Life) |
| Brake lines — Inspect condition, damage |
| Brakes — inspect function, pad thickness. Replace as necessary (same pads on both S and SM, even though different discs). * Front: FA185R * Rear: FA131R |
| Brake fluid — Check level (between lines). Note that brake fluid drops with brake pad wear. |
| Tires — Inspect condition and tread depth |
| Spokes and spoke nipples — check tightness using your hand, squeezing spokes, or hitting with a small bar (listening for a dull thud). If one spoke is looser, tighten it. Spoke nipple torque — 2.7 Nm / 2 lb-ft / 24 lb-in |
| Chassis bolts and nuts — Tighten |
Drive Chain Maintenance on the Suzuki DR-Z400S / SM
Check the drive chain condition every time you use the motorcycle, or at least at every service.
Drive chain slack
Check the drive chain slack every time you use the motorcycle. The chain should have 40-50mm (1.6-2.0 in) of deflection at the loosest point.
Measure the drive chain slack by moving the middle of the bottom of the chain up and down (with your finger or anything), using a ruler to measure deflection.
Target maximum deflection: 40-50mm (1.6-2.0 in)
If it’s too loose (or has been over-tightened), you need to adjust the slack.
To adjust slack, put the motorcycle on its side stand.
- Remove the axle slider (removing the bolt from the inside of it)
- Loosen the axle nut and the left and right lock nuts on each side
- Turn the adjuster bolts until the chain has the right tension. Make sure you adjust them both by the same amount — the adjuster lines should be the same on each side.
- Tighten the axle nut (110 Nm / 80 lb-ft)
- Tighten the lock nuts.
Tyre size and tyre pressure for the Suzuki DR-Z400
The manual gives the following tyre specs for the DR-Z400, as well as the following recommended tyre pressure ranges when cold.
The below specs are for the latest iterations of the DR-Z400.
DR-Z400S (Dual sport) tyres
| Tyre | Size | Brand(s) | Tyre pressure (cold) |
|---|---|---|---|
| Front | 80/100-21 M/C 51P, tube type | BRIDGESTONE TRAIL WING-41 | Solo/Dual: 125 kPa (1.25 bar) / 18 psi |
| Rear | 120/90-18 M/C 65P, tube type | BRIDGESTONE TRAIL WING-42 | Solo: 150 kPa (1.50 bar) / 22 psi Dual: 175 kPa (1.75 bar) / 25 psi |
DR-Z400SM (Supermoto) tyres
| Tyre | Size | Brand(s) | Tyre pressure (cold) |
|---|---|---|---|
| Front | 120/70-R17 M/C 58H, tube type | Dunlop SportMax D208F SM | Solo/Dual: 175 kPa (1.25 bar) / 25 psi |
| Rear | 140/70-R17 M/C 66H, tube type | Dunlop SportMax D208 SM | Solo: 200 kPa (2.0 bar) / 29 psi Dual: 225 kPa (2.25 bar) / 33 psi |
About the Suzuki DR-Z400S / DR-Z400SM
The Suzuki DR-Z400 is an enduro / dual sport / supermoto platform that has been around for a long time and has been essentially unchanged mechanically for decades.
The main two versions of the Suzuki DR-Z400 available today (and for a while back) are the
- DR-Z400S: The enduro / dual sport
- DR-Z400SM: The supermoto
You could consider the DR-Z400SE to be the little sibling of the Suzuki DR650, but it has some pretty important differences and isn’t just the smaller version of the bigger dual sport.
The core of the Suzuki DR-Z400 (both S and SM) is a 398-cc liquid-cooled single-cylinder engine. It’s fed by a single 36mm Mikuni carburettor and makes what seems like a modest 29 kW (40 hp) at 8500 rpm, or 39 Nm (29 ft-lb) of torque at 6600 rpm.
But to quote power and torque specs would be a disservice to the DR-Z400.
The engine is actually an extremely versatile one, good for both on-road speeds from urban to highway (though you probably won’t stay on the highway for long), as well as for doing wheelies or climbing over rocks when going offroad.
The main way to understand the differences is that the DR-Z400E / DR-Z400S / DR-Z400SE is the dual-sport version with a big 21-inch front wheel, long-travel suspension, and slightly less braking power, whereas the SM has street 17-inch wheels, better braking, and less suspension travel.
| Spec | DR-Z400S | DR-Z400SM |
|---|---|---|
| Purpose | Dual sport (Street legal) | Street/Supermotard (Street legal) |
| Years | 2001+ | 2005+ |
| Compression ratio | 11.3:1 | 11.3:1 |
| Front suspension | Conventional fork, adjustable compression and rebound damping, 288 mm / 11.3 inches travel | Showa inverted fork, rebound and compression damping adjustable, 260 mm / 10.2 inches travel |
| Rear suspension | Fully adjustable rear shock with high and low-speed compression damping adjuster, 295 mm / 11.6 inches travel | Fully adjustable rear shock with high/low speed compression damping, 276 mm / 10.9 inches travel |
| Front brake | 250mm disc, 2-piston caliper | 300mm floating disc, 2-piston caliper |
| Front tyre | 80/100-21, tubed | 120/70 R17, tubed |
| Rear tyre | 120/90-18, tubed | 140/70 R17, tubed |
There are some other differences, like in the length of the swing-arm.
Also, in prior years there was an off-road-only version of the DR-Z400 sold, with a different carburettor and camshafts, and a different compression ratio. Some of those came with a kick starter only.
Those who have ridden both versions of the bike say they’re completely different bikes, but nonetheless, their maintenance is quite similar.
Both the DR-Z400E and DR-Z400SM are easy to maintain. You have easy access to the air filter and clutch, making minor and major jobs a cinch. It has old-fashioned technology — a carburetor, LCD screen (heck, I’ve seen worse), and halogen lighting, but in many parts of country or world, this makes it much easier to find parts.
The tricky part is the valve service. The valvetrain on the DR-Z is a shim and bucket type, which means you have to remove the camshafts and do arithmetic (egad!) to adjust the clearances, plus have other shims on tap.
It doesn’t come up often, though, and the wise ones at Thumpertalk.com say that keeping your air filter clean and not over-revving the engine will keep you form needing a valve service for a long time.
Reference — Manual for the Suzuki DR-Z400 / SM.
The above maintenance schedule comes directly from the user’s manual for the Suzuki DR-Z400. It’s identical between the two models (the E and SM).
You can download it for recent year models from here.
