The DR650SE engine has an outstanding reputation for long, trouble-free service life. Of course, it should go without saying that proper maintenance is the key to that longevity, and Suzuki's engineers have made your life easy in that regard. The DR650 is a remarkably friendly bike to work on, generally. It's also a well designed, low-stressed engine, with an excellent lubrication system.
Nothing's perfect, though...
We don't want to scare you off but even the best engineered mechanical devices can have issues in assembly and design. The DR650 is no exception. Suzuki did a great job with the DR650 but over the years certain items have surfaced in a repeating pattern. We will cover those items and let you know what years the issues affect below.
Starting with issues that may affect every year model of the 96-Present DR650SE:
- Neutral Sending Unit (NSU)- This is a sensor within the engine that lights the "Neutral" indicator on the dash. It is held in place by two screws. There are very rare instances where these screws have backed out and fallen into the engine. I'm sure everyone can imagine the carnage if one of those screws managed to bounce between a connecting rod and a crankshaft lobe at 5000 rpm. Now throw in the image of hot oil spilling out of your engine all over the rear tire at 70 mph as the engine locks up. Not pleasant. Clearly, this is a worst-case scenario, but you get the idea.
- The extremely rare cases where these screws fall out seem to happen to higher mileage bikes, but that's certainly no guarantee.
- There is one possible warning sign. If your neutral light stops working, even intermittently, SHUT DOWN THE BIKE UNTIL YOU FIND OUT WHY. The fix requires removing the engine cover, appling threadlock and re-tightening the screws. Some prefer to remove the sensor entirely. Crisis averted...
- A magnetic oil drain bolt may go a long way to catching a stray screw before it has a chance to cause more significant damage. Some chose to replace with NSU screws with 5mm x 20mm hex head bolts (to engage a few more threads) and 5mm serrated lock washers.
- NSU Links:
- Avoiding NSU Problems by macdesign (ADV Rider).
- OHH $hit Oil Change... by chaos_magic_man (Thumpertalk)
- NSU Checkup "How To" by greenlizard (DRRiders.com)
- And while you are checking your NSU screws.... Primary Reduction Gear Crank Nut: There have been a number of documented cases of the primary gear retaining nut coming loose and backing off. While you have the clutch cover off it would be a good idea to check this nut for proper torque (72.5 ft lbs). The nut is a left handed thread. If you find the nut is loose on your machine you will want to check the condition of the key. If there is any side wear or grooving replace the key. Using some removable threadlocker on nut would not be a bad idea either.
- ====Countershaft Seal: This is rare but, if it happens, could be a disaster. The seal around the countershaft (front sprocket shaft) can be pushed out, which essentially dumps all oil from the engine/transmission. This could cause loss of control due to oil getting on the rear wheel, damage to the engine, and of course the 'bike will be unridable until the seal reinstalled and oil added. There is much debate on the cause, but there is also a simple, cheap fix available - several "seal retainers" are available commercially, or you can build your own.====
- CS Seal Links:
- The upper drive chain roller- It needs to go away! Remove it and fill the mounting boss in the frame with either a loctited in 8mm-1.25 x 25mm set screw flush with the boss or just fill the hole with some silicone to prevent water from entering. This roller tends to break off the boss taking a large chunk of the frame with it. It serves no purpose, in the position Suzuki installed it, other than to cause many DR650 riders grief. This roller's mount can not withstand the torque of the motor which is applied to it when the suspension is compressed and the roller intersects the direct line of sight of the chain from countershaft sprocket to rear drive sprocket. Removing it does not cause any issues with the chain hitting the frame or air box like on a MX bike... but keeping it on the bike has enough documented cases of disaster that not removing it is asking for punishment. :-)
Speaking of punishment:
- Do it now!!! Upper chain roller went bye bye (DRRiders.com)
- upper chain roller removal....crack frame (DRRiders.com)
- Upper Chain Roller (DRRiders.com)
- Lots of problems (DRRiders.com)
- The upper chain roller went AWOL (Thumpertalk)
- Chain Roller Hole (Thumpertalk)
- G#$%D$%& chain roller (Thumpertalk)
- To the nonbeliever's, upper chain roller (Thumpertalk)
- top chain roller (Thumpertalk)
- Just take stupid thing off. (Thumpertalk)
- mayday!!!!upper chain roller broke off!! (Thumpertalk)
- Also see cutout switches under Electrical
- Header weld- Here's one area where Suzuki's quality control consistently slips. At the header flange, where the exhaust pipe meets the cylinder head, is often a big glob of weld . Right where you don't want it, right where it will collect heat and restrict exhaust flow. If you modify the intake side of the engine at all, you would do well to examine this weld, and grind it smooth, if needed. Be aware that you can remove too much material, and possibly weaken the pipe's weld to the flange. You can strengthen this area by welding a bead around the outside, where the pipe and flange meet. Also inspect the header pipe for any hairline cracks which cause exhaust leaks.
- Dry steering head bearings. Uncertain if this is isolated to specific years, or simply an assembly oversight from the factory, but some steering heads have very little lubricating grease on them. If you catch it early, it's easy to fix (just slather grease all over both the upper and lower bearings). If you wait too long, the bearing will be ruined and you will need to go through the tedious task of removing the forks and steering head, driving off the lower bearing, and replacing both bearings and races.
Issues that (can) affect the 96-2003 DR650SE year models:
- Leaky base gasket- The paper cylinder base gaskets first installed by Suzuki can suffer leakage. The norm is for the gasket to leak after time. The exception is no leaks. If a leak does develop, it is often no more than a slight weep, and many owners just live with it. Some have managed to stop the leak with a bead of sealant. Overfilling the crankcase might aggravate the trouble, so take care to keep the oil level correct. In late 2003 Suzuki changed to a steel laminated gasket that took care of the issue. The steel gasket has a small tab with a rivet in it on the front right corner of the engine below the oil cooler.
- 3rd gear issues- Some DR's can have a pronounced whine in 3rd gear which can be caused by the hardening wearing off or a badly cut gear. Not catastrophic but annoying anyway.
- 3rd gear has also been known to disintegrate in a small number of cases. Unfortunately whine or lack of is no indication either way something is going to happen. So far there have only been 30 or so documented cases as at 17th Feb 2012 in the US/OZ/NZ out of the many thousands of DR's running around out there and some racking up very high mileages with no problems at all.
- Riding conditions may play a part as the Australian bikes affected seem to be at about 20-30,000km whereas the New Zealand/US bikes were between 40-60,000km.
- Suzuki changed the part number for 3rd gear in 2006 and 2008 and so far the years represented in the failure list are from 1999 to 2009.
- The 3rd gear cog is under load in 3rd, 4th and 5th gears and is the hardest working of the cogs.
- If you are going to have the cases apart for any reason, for peace of mind it would pay to replace this $70US part.
Issues that affect the 98 and part of the 99 DR650SE year models:
- No starter clutch torque limiter- "1998 and early '99 were equipped with a solid idler gear in the starter reduction gear set that created a problem when the engine kicked back during shutdown, breaking out the gear bearing bosses. This occurrence is typically caused by pre-ignition, resulting from poor fuel quality or excessive lean fuel-air mixtures, sometimes arising from improperly installed/tuned aftermarket modifications. This also breaks out and destroys the left case half due to its rigid design. The case halves always come in matched pairs and cost in excess of $650US not to mention labor charges to change all internal parts into new cases. This should not be taken lightly. '96 and '97 had the torque limiter gear that is designed to slip due to a preloaded slip clutch arrangement. In an effort to assist consumer with this possibility, [Suzuki] went back to this design in mid '99 after vin # X2100561 so if your Vin # predates this you should consider installing this updated item shown above." -quoted from the Keintech website.
There is a Youtube video providing a quick visual checklist of these issues and several others: