This post was originally published on Feb 21, 2021, but has been thoroughly revamped and improved since then.
This is the maintenance schedule and associated service intervals for the Suzuki Boulevard S40, a.k.a the “Savage”, or the LS650.
The Suzuki Boulevard S40 (formerly Suzuki LS650 Savage) is a lightweight cruiser motorcycle with a single-cylinder engine. It was called the Savage from 1986 to 2004, and renamed as the Boulevard S40 from 2005.
The Suzuki LS650 has remained unchanged except for minor cosmetic improvements, receiving a 5 rather than 4 speed transmission in 1993. It has always been a simple motorcycle — easy to ride, modest power, and an extremely easy-to-service single-cylinder engine that’s in plain sight.
With a weight of 381 lb (173 kg), Suzuki markets the S40 as an entry-level model to the cruiser line. With a seat height of 28 inches and flatter handlebar, the Savage is also suitable for shorter riders.
The humble “Savage” has unfortunately been retired from nearly all markets, though it has been available in the US for longer. So take care of yours if you have one!
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Suzuki Boulevard S40 / LS650 “Savage” Maintenance Schedule
Below is the maintenance schedule for the Suzuki Boulevard S40 / LS650 “Savage”.
- Follow the earlier of distance- or time-based intervals.
- At the end of the maintenance schedule, continue it in the pattern shown.
|mi x 1000||0.6||4||7.5||11||14.5|
|km x 1000||1||6||12||18||24|
|Annual service checklist (see below) — Perform||✓||✓||✓||✓||✓|
|Engine oil — Replace (Kawasaki 10W-40 Engine Oil)||✓||✓||✓||✓||✓|
|Oil filter — Replace (HFA3608)||✓||✓||✓||✓||✓|
|Air filter — Replace (K&N SU-6595)||✓||✓|
|Valve clearances — Inspect / adjust||✓||✓||✓||✓||✓|
|Spark plugs — Inspect||✓||✓|
|Spark plugs — Replace (NGK DPR8EA-9)||✓||✓|
|Vapor hose (California model only)||Replace every 4 years|
|Brake hoses — Replace||4 years|
|Brake fluid (Castrol DOT 4) — Replace||2 years|
|Front forks — Inspect for leaks, pitting||✓||✓||✓|
|Rear suspension — Inspect for leaks, pitting||✓||✓||✓|
Suzuki Boulevard S40 / LS650 Savage Annual Service Checklist
Below is the annual service checklist for the Suzuki Boulevard S40. Do it according to the schedule above.
Some of these items are meant to be done more frequently and are mentioned at the top.
|Suzuki Boulevard S40 Annual Service Checklist|
|General lubrication — Perform|
Every 600 mi / 1000 km
|Air filter — Clean|
Clean every 2000 mi / 3000 km
|Drive belt — Inspect|
Inspect every 2000 mi / 3000 km if possible
|Battery — Check specific gravity of electrolyte and charge level|
|Fuel lines — Check|
|Automatic decompression cable — Inspect|
|Throttle cable play — Check (2-4 mm / 0.08-0.16 in)|
|Idle speed — Check (1000-1200 rpm)|
|Clutch — Check free play, and lubricate cable (Protect All Cable Life)|
|Brakes (front disc, rear drum) — Inspect|
|Brake fluid — Check level (between lines). Note that brake fluid drops with brake pad wear.|
|Tires — Inspect condition and tread depth|
|Steering head bearings — Check for smooth operation|
|Chassis bolts and nuts — Tighten|
|Cylinder head nuts, exhaust pipe bolts and muffler connector bolt — Tighten|
Checking the Drive Belt
Suzuki recommends checking the drive belt regularly, between services — every 2000 miles / 3000 km.
Check the drive belt for
- General wear — look for cracks, missing teeth, or other evidence of wear
- Tension (using a tension gauge). Put the tension gauge as shown in the diagram below with the motorcycle on a side stand. It should be on a locating tab and held at a right angle to the drive belt.
If the tension is out of range, use the method mentioned in the owner’s manual (see below) to re-tension. In a nutshell
- Loosen the axle nut.
- Loosen the lock nuts
- Turn both adjusting bolts, turning the same amount to keep the belt in alignment.
- Re-tighten the axle (65 Nm / 47 lb-ft) and the lock nuts.
Tyre size and tyre pressure for the Suzuki Boulevard S40
The manual specifies these tyre sizes and says the S40 ships with these tyres standard. It also recommends the following tyre pressures when cold.
The Boulevard S40 has tubed tyres.
|Front||100/90-19M/C 57H||IRC GS-18F||200 kPa (29 psi)|
|Rear||140/80-15M/C 67H||IRC GS-18R||Solo-dual: 225-250 kPa (33-36 psi)|
About the Suzuki Boulevard S40
The Suzuki Boulevard S40, formerly known as the LS650 Savage, is a simple and stylish motorcycle by Suzuki.
The Boulevard S40 is powered by a square 652 cc engine. It has a bore and stroke of 94 mm, which is why it’s called “square” (though obviously it’s a cylindrical shape).
The engine is tuned very mildly, with an 8.5:1 compression ratio. This is not a high-performance bike!
Bear in mind that even though the Boulevard S40 and Suzuki DR650 both seem to have long-running air-cooled motors, they’re different. The DR650’s is oversquare, for example.
The engine is very simple in design, with a single Mikuni BS40 carburettor, air cooling, a single overhead cam with two lobes — one for intake and one for exhaust. So adjusting the valves is not overly complex. See this thread on suzukisavage.com for more info.
Even though the valve inspection interval is with every oil change, many owners never do it until they notice valve tappet noise or suffering performance.
What’s very interesting is that the Suzuki Boulevard S40 is still being produced with a single carburettor, a Mikuni BS40 CV carb, just like back in 1986. If you’re looking for a motorcycle to learn how to service a carburettor on — this is one!
Suspension on the Suzuki Boulevard is very simple, with a telescopic fork up front and a single shock at the rear. There’s a disc brake up front and a drum brake at the rear. It’s all so moderately spec’d that it’s silly to mention it, as you don’t buy or ride the Suzuki Boulevard S40 on specs. Just bear in mind you’ll have to replace brake drums at some reason.
Service intervals on the Suzuki Boulevard S40 are as you’d expect for an air-cooled single. Change the oil every 3500 miles or 6000 km, and inspect the valve clearances at that point too (if you want). Replace the spark plug every second service.
Manual for the Suzuki Boulevard S40
The above maintenance schedule comes directly from the user’s manual for the Suzuki Boulevard S40.
Below is a copy of the Suzuki Boulevard S40’s 2017 manual for archive purposes.
You can download the manual for the Suzuki S40 from here.