Suzuki DR650


I've been riding "dual-sport" and off-road motorcycles for many years. Mostly, however, on lighter weight bikes that function well in rugged conditions but may not be well-suited for long jaunts at highway speeds. Some of my riding pals have been "adventuring" a bit lately which often involves longer travel distances and a higher percentage of pavement. I've decided to join them on some of these adventures. And, while my DR350 is a splendid dual sport bike, when it comes to extended paved connectors typical of adventure trip, it needs a little longer legs. However, I like the little Suzuki SO very much that I thought I give it's big brother, the DR650SE a try. It's amazing how similar these bikes are. The construction and design of the DR650 in most cases is nearly the same as the DR350, except everything is just a little larger.

I wrote that about three years ago. I'm on my second DR650 now. Still like this model a lot for my kind of riding.

DR650 #1

I bought this 2001 DR650 "pre-owned" as is my normal modus operandi. It had about 23K miles on the clock and the previous owner had been using it as a daily commuter. He had ridden it very little off-pavement. It was wearing 90/10 street tires when I got it and the suspension was in the "lowered" position. Mechanically it seemed sound except for an oil leak which turned out to be the gasket around the cam chain tensioner. On the plus side it already had the IMS 4.9 gallon tank, a custom Sargent seat and a nice set of sturdy handgaurds. Those are all things I would have added had they not been installed already. This year model has the paper cylinder base gasket that some have reported as leaking. This one doesn't (at least not yet). And, it is past the period where Suzuki tried to save a few bucks by leaving out the starter kickback clutch. That resulted in quite a few catastrophic failures if one can believe all the reports on the Internet. The PO's taste is motorcycle aesthetics differed a bit from mine in that the bike was painted all black (with a lot of scratches!). Suzuki DRs can't exactly be considered beautiful bikes by any standard but there was definitely room for improvement on this one IMO.

 

 

Two weeks later and now we're getting somewhere:

  • Oil leak fixed by replacing the cam chain tensioner gasket,
  • Raised the ride height back to normal which means changing the fork spacer and rear shock mount plus welding an extension into the shortened side stand
  • Stripped the paint off the fenders and side covers and repainted the luggage rack silver.
  • Remounted the rear turn signals so they are less vulnerable in a tip-over.
  • Added EMGO folding dual-sport mirrors.
  • Cut down and remounted the little BMW windscreen (which does make a difference at highway speeds).
  • Vastly improved throttle response by shimming the needle .030", removing the airbox snorkel and adding an extended idle mixture screw. I'm running the stock (#140) mainjet, stock air-box with a twin-air filter and a stock exhaust. With this setup the bike runs very well at all speeds, has no soot in the pipe and delivers around 55-60mpg. Plus, and this is important to me, it will chug along like a John Deere when asked.

The bike still had some "issues" at this point. IMO, it's suspension was FAR too stiff and there was a unacceptable level of handlebar vibration.

Two more weeks and making progress:

Since this will be an "adventure" bike that I will travel on, it needs luggage of course. I have some soft-sided bags I used for years on my dual-sports and all that was needed is some bag mounts to make those work.

Adding the Vibranators AND reducing the torque on the handlebar "soft mounts" made a dramatic difference in handlebar vibration. It's only slightly more than the DR350 now and is quite acceptable. The Intimidator fork cartridge inserts were a BIG step in the right direction in that the forks became much more responsive; BUT, they were still too stiff for my riding style. Seems to me this DR650's suspension (don't know if it was stock or not) was tuned much more towards spirited pavement riding than for off-road rugged terrain. That had to be fixed.

The problem, I thought, was that the progressive wound springs in the forks (possibly aftermarket?) were OK at the beginning of the compression but very quickly became too stiff resulting in a lot of "kicking up" of the front end in rugged terrain and consequent loss of control. These springs might have been about right for desert racing but at 1st and 2nd gear speeds on our rugged eastern woods roads (and occasional non-roads) they made the bike unmanageable. I believe an off-road bike needs to be fairly "plush" to absorb the irregularities of rugged terrain. Just watch the bikes and buggies that run the Baja or the Dakar, they are super compliant. I'm not going to be jumping school buses or running at Dakar speeds so I needed more compliant springing on this bike. The "right" thing to do of course was to contact a suspension expert (that would have been easy since we have one of the country's best MX suspension tuners right here in my hometown) but being chea... uh, frugul by nature, I decided to try something a little different. I have several sets of DR350 forks in my parts inventory so I pulled the springs from a pair of those. As seen in the picture, the 350 springs (the lower one) are straight wound and appear to be much less tightly coiled than the 650 springs. They were also about 3 inches longer so I cut them off to the appropriate length realizing that cutting them would increase the rate. Although I don't know for sure what the actual "rate" is for the cut springs they don't seem vastly different but the ones I replaced. Based on the specs for the DR350 springs and just roughly calculating what reducing their length by 3" would do, I'd estimate the rate at .50kg/cm. However, being straight wound, they are definitely softer under high compression giving me more use of the available fork travel. This change plus the Intimidator inserts has resulted in a BIG improvement in fork compliance. In January,2013 I added a custom Cogent Dynamics shock/Olins spring to big DR. I was really pleased with the suspension on both ends!

 

During the summer of 2012 I rode the DR650 #1 from Jellico, TN (old start point of the TAT) to Van Buren, ME on what we're calling the Maine Adventure Trail (MAT). That's about 2500 miles of as much unpaved surface as possible though TN, VA, WV, MD, PA, NY, VT, NH and ME.

It was a GREAT trip and the big DR was heavily loaded but did just fine. In fact, I was truly amazed by it in a couple of the rougher sections where it just tractored through.

 

DR650 #2

At 42K miles DR650#1 was still running like a champ. However, early in 2013 a friend wanted to part with a non-running '99 model having only 11K miles and made me an offer I couldn't refuse. So, I brought the older but lower mileage bike home and proceeded to swap the "good stuff" to it. In the end it didn't look much different from #1 which I sold. It was just less used.

Visible changes are:

  • Post 2001 headlight and shroud
  • DRZ400 taillight
  • Mods to bag racks to accept DirtBagz
  • Renasco Racing seat
  • Custom dash with TrailTech Vapor 2 Speedo/Tach, etc

Non visable changes are:

  • Replacement of the Ricor Intiminators with Cogent DDC cartridge emulators and new .525 springs.
  • Carb retuning - 55-60mpg + 100mph capable - really happy with this...

DR#2 has done the western part of the TAT, the Southern half of the Western Continental Divide and hundreds of day rides. It's a keeper.

Which brings be to probably the most important part of this missive. The suspension. The DR650 is a great bike in many ways and depending on the weight of the rider and how the bike is used, the stock low-end suspension components may or may not be adequate. I wanted some improvements in that area.

For the edification of suspension tuners... my experience on the DR650

The first DR650 (an '01) was bought with 22K miles and sold still running great with 42K. The second one (a '99) had 11K when I bought it and as of January 2015 has about 39K. Both were ridden as dual-sport / adventure bikes. Both as local day-ride bikes and on multi-week adventure tours (Trans-America Trail, Rocky Mtn Continental Divide, etc). Point is, the bikes have been utilized for what I believe they were intended. For reference I'm around 200lbs - probably close to 220 in gear and on the trips carry up to 70lbs of "luggage". I am a mature rider (69) and so I don't ride "aggressively" any more but I have been riding for 57 years and have a few Enduros under my belt so when riding with less experienced riders I usually have to wait. OTOH, the younger guys with experience are usually waiting on me. I like a plush ride that absorbs the terrain and I like to maintain traction and forward motion rather than kicking roost and lofting the front wheel. That said, the purpose of this write up is to share my experience with DR650 suspension.

The first DR had stock suspension when I bought it. Over time I replaced the shock with a full monty Cogent rebuilt shock and .76 kg/mm Ohlins spring and valving for my weight. That resulted in an awesome improvement in control but a somewhat harsher ride. A good trade off IMO. Also on that bike I reworked the forks with Ricor Intiminators and straight rate .50 kg/mm (estimated) springs. Again a dramatic improvement over the stock front end. The Intiminators virtually eliminated brake dive and provided a much more supple ride over smaller irregularities of off-pavement riding. The straight rate springs made the front MUCH more stable as the OE progressive springs tended to bounce the front end up unpredictably on big hits making it hard to hold a line.

Okay, along comes a deal I can't pass up on the '99. It came to me with a Cogent rebuilt shock (.67 kg/mm Eibach spring) and valving for a 180-200lb rider. The bike also had Racetech Gold Valve emulators in the forks with drilled damper rods and the stock progressive wound springs. Loved the shock but hated the forks which provided great control but just beat my hands and shoulders to death. So before selling the '01 I removed and stored the Cogent shock and swapped the Intiminators and straight wind springs to the lower mileage '99 forks and called it good. Rode it happily that way for about 20K miles.

Flash forward... Cogent starts selling the DDC cartridge emulator with rave reviews on ADVRider. So, I had to try those. Got them installed with new .525 kg/mm springs and it's even better yet. Maybe a little firmer than the Intiminators but the control is just awesome. It simply goes where you point it now. Still great front fork action with very little brake dive but the biggest difference is the feeling of control particularly at higher speeds. They really are better for me. Although definitely a lesser spring rate than the front, for now I'm keeping the .67 rear setup but I have the .76 shock and spring on the shelf just in case. Might put it on before my next adventure trip with luggage.

In defence of the Ricor Intiminators, they are designed to provide a supple ride while eliminating brake dive - a great idea but the DDCs work better for off-road applications IMO. We have Intiminators in both of our street bikes (DL650 and SV650) and we are very happy with them there.

Summary
'01 DR650 stock suspension
Very soft but comfy and controllable at lower speeds - not so much at higher speeds.

'01 DR650 with
- Intiminators and .50 kg/mm straight wound fork springs, minus 3mm preload*, 165mm oil level* (5 wt)
- Cogent shock with .76 kg/mm spring
Vastly improved - a bit stiffer but more controllable at speed. Reduced brake dive, more supple fork action over minor ripple surfaces. Much less "kick up" on big hits. Handles added weight of luggage better.

'99 DR650 with
- Racetech Gold Valve emulators and OE progressive springs
- Cogent shock with .67 kg/mm spring
Love the rear, hated the forks because they were so harsh. The Racetech emulators are tunable but I did not attempt to alter the settings - maybe they could have been tuned better for me but I chose to replace them.

'99 DR650 with
- Intiminators and .50 kg/mm straight wound fork springs, minus 3mm preload, 165mm oil level (5 wt)
- Cogent shock with .67 kg/mm spring
Great solution but in retrospect the forks were a little more vague than I knew

'99 DR650 with
- DDCs and .525 straight springs, 10mm preload, 130mm oil level (5 wt)
- Cogent shock with .67 kg/mm spring
Very good but the forks were a little more harsh on big hits than I liked. Rick suggested less oil (more air cushion)

'99 DR650 with
- DDCs and .525 straight springs, 10mm preload, 150mm oil level (5 wt)
- Cogent shock with .67 kg/mm spring
The best yet. The front spring rate is definitely higher than the rear but for now I'm leaving it. At some point I may put the .75 Cogent shock back on but for now I'm lovin' it.

Yeah, it's been a trip. MUCH thanks to NCRick (Cogent Dynamics) for his patient help.

Definitions
* preload = the distance from the top of the extended fork to the top of the spacer - a minus value means the spacer extends ABOVE the fork tube. This is actually kind of an inverse way of looking at preload but it is the way the Cogent folks like to talk about it. The cap is 18mm deep (I think) so 10mm as measured by this technique means the spring is actually compressed 8mm when the cap is installed. The -3 value for the .50 springs means those springs were compressed 21mm.
* oil level = the distance from the top of the compressed fork without the spring or drop-in to the surface of the oil so a larger number means less oil and more air cushion.

6/07/15 Update: After some seat time, I dropped the oil level in the forks by another 15ml so the level is approximately 165mm as specified in the service manual. The extra air cushion is not dramatic but is noticeable. I LIKE it.

I like the DR650 a lot in many, many ways. It is, of course, a bit heavier than my kickstart-only DR350. About 50lbs heavier in fact and that's definitely noticeable. But some of that is offset by the 2" lower seat height. As you might expect the 650 motor is much more torquey (it's a tractor!) than the 350 and has it longer legs on the highway. OTOH the DR350 is a 6-speed and that allows a wider range of gear ratios. It's 2nd gear is numerically the same as 1st gear on the 650 and that means it's a far better "crawler" when the going gets rough. Combine that with the 350's 9.5K rpm redline (versus 7.6K on the 650) and 50 lbs less weight and you have a more tractable motorcycle for off-road use. The 650 excels on pavement of course where it's turning about 2K rpms slower than the 350 at 60mph. Also, being larger, it is a much better "mule" for carrying gear and luggage.In addition to my 200lbs I was hauling about 70 lbs of luggage and camping gear on the MAT trip. No sweat. I don't think the DR650 can replace the DR350 for rugged off-road use. And, I don't think it can replace my DL650 V-Strom for touring. BUT, it does a lot of things very, very well and bridges the gap between unpaved and paved secondary roads beautifully. Being a single cylinder without a faring it's not a bike well suited for interstate highway travel but that's always my last choice anyhow.

Bottom line, if I could have ONLY one motorcycle, I'm pretty sure the DR650 (well, maybe a new one), would be THE one.

And then...

In December of 2016 I bought a new (yes NEW!) leftover 2015. First new motorcycle for me since 1971 when I bought a new Suzuki T500 Titan.

About 6 weeks later it looks a lot like my old one... just with 42K fewer miles and fresh Cogent Dynamics suspension (as described above)

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