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I've written six 4x4 Jeep® and truck books plus a Harley-Davidson book. Most know me as a 4WD Jeep, light 4x4 truck and automotive guy, some as a Harley-Davidson author, and few are aware that motorcycling has played a role in my life. My earliest on-highway vehicle operators license, at age 14, was a Nevada Scooter License. Unique to that era, without the sanctions of insurance and high registration fees, scooters were a recognized means for getting to high school. Nevada was the fifth largest state in the U.S.—with the smallest population at the time... I rode a Cushman on the highway and a friend's Honda Trail 55 on dirt. By sixteen, my attention turned to Jeep 4WDs and muscle cars, though I never turned my back on motorcycling. My first return to two wheels was a series of three pre-owned BSA motorcycles (each '69 model year by sheer coincidence). One was a Victor 441 B44, allegedly a scrambler but rather ill-equipped for the dirt by today's standards. Cycles with vertical rear shocks and short stroke, highway style front forks were hardly off-pavement material. (This was "On Any Sunday" stuff, and many of us, including J.N. Roberts, Steve McQueen and Malcolm Smith, rode near vertical rear shock machines.) If nothing else, at nearly 10:1 compression, the Victor was the quintessential "thumper" and a good way to learn about compression release starting! Several road bikes have been notable, my BSA 650 Lightning and 750 Rocket III, a BMW R80GS (that hardly met "off-road" standards despite the implications), a BMW K1100LT that was a highway delight and a Gold Wing GL1500 that I can only call "a beast"—ridiculously cumbersome and far beyond the realm of a flick-about motorcycle. My takeaway from the Gold Wing was that I'd never ride a cycle over 500 pounds again. So much for today's "cruiser", touring bikes and dressers! As long as I can swing a leg over the saddle, I'll take a sport bike under 500 pounds, hands down. We discovered serious dirt riding and cycles two decades ago when youngest son Jacob was 11-years-old. I wanted him to ride sensibly, and a vintage XR75 was the choice after a brief detour with a Kawasaki KX80. Honda's "red" assets caught our fancy, and I acquired a used XR200R to accompany Jacob. That quickly grew to an XR350R, passing the XR200R to Jacob (typical family maneuver with motorcycles). The XR350R had been prepped and "blueprinted" by the late Rick Sorensen for his daughter Natasha to race. Rick was a topnotch aircraft A&P mechanic and motorcycle tuner...In pristine condition, this cycle has remained in my stable since, impressive enough to warrant the acquisition of an XR500R counterpart. Both are '84 model Pro-Link chassis, the 500 boasts dry-sump engine oiling...hot for the era! Yes, I do ride dirt motorcycles—with passion and vigor, desert enduro type terrain my favorite, single track or destination "overlanding" well within bounds as well. Today's cycles draw me toward an XR650R Honda for my current kind of riding, fitted with a Dakar tank and dual-sport retrofit kit, ready for long distance travel. We live at Northern Nevada, a virtual Mecca for dirt riding and backcountry motorcycling access! A CRF450X might be a consideration, though "Dust to Glory" and the XR650R are forever etched in my mind—how can Johnny Campbell, Andy Grider, Steve Hengeveld and Mouse McCoy be wrong? The XR650R Honda is the ultimate icon, a virtual cult dirt bike for the desert. So, don't be surprised if I'm regularly peeking into this forum and even adding my two-cents worth. Dirt motorcycling is on my mind—a lot. It's an incentive to stay in top physical condition, to keep my reflexes primed and not to let chronological age blur my self-concept. I'm still healthy, quick reflexed, and more than ready to ride a converted dual-sport—anywhere, any time!—Moses Ludel At left is our third XR Honda, an XR350R. We have a fourth one, too, an XR500R, for possible restoration. Or maybe we'll add an XR650R built with Baja/Dakar trim with a dual-sport conversion!...Tying to the Karavan dual-motorcycle trailer, it's time to ride in the desert. The magazine's XJ Cherokee (right) provides a good tow platform for getting the dirt bike to a trailhead or desert dry lake. A dual-sport conversion would eliminate the tow need. This cycle has done a variety of chores for more than a dozen years, included getting me around with a video camcorder for covering the Stampede Race and King of the Hammers. -
Snow drifts blocking your favorite dirt bike riding venues? Rainy season drenching the ground and making knee-deep mud? Does the down time in the off-season have you itching for a good ride? While you're going to the gym and anticipating the next riding season, check out this well done motorcycle enduro and trials technique instructional video depicting pro riders at South Africa! A hearty thanks to these professionals for sharing...
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Every once in a while we stumble onto some down to earth humor and genuine entertainment. All dirt bike riders who are now 50-or-older or will someday be that age will appreciate this 8-minute time out. Congratulations to these Down Under riders who know how to have a good time—and obviously have their priorities in order! Enjoy! Moses
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Given the opportunity to test the Pulstar® PlasmaCore spark plugs, we targeted the magazine's Honda XR350R and XR650R motorcycles. The XR350R is air cooled, the XR650R has liquid cooling. Both cycles use fixed jet, slide type carburetors. The XR350R has twin Keihin carburetors, the XR650R uses a single, large Keihin carburetor. We rode the bikes extensively. The XR350R is OHV permitted for dirt only use, and that testing took place in high desert and mountainous terrain, both dirt roads and single track. The XR650R with its dual-sport conversion received a full test at both dirt and asphalt riding. The HD video shares installation details, riding footage and an evaluation of the Pulstar® spark plugs: The magazine article is available at: http://www.4wdmechanix.com/Testing-the-Enerpulse-Pulstar-Spark-Plugs.html. We will continue testing and discussing these spark plugs at the magazine and these forums! Here are our test results and findings: Honda XR650R Motorcycle—This bike is a highway legal dual-sport conversion and ongoing project feature at the magazine. The top-engine is freshly rebuilt to "blueprint" standards, featuring a cylinder head overhaul by L.A. Sleeve Company and a moly-chrome cylinder liner with new piston and rings. We performed all work as a how-to project that became a feature HD instructional video at Vimeo On Demand. The head and upper engine work includes a Hot Cams Stage 1 camshaft. Spark timing and valve timing are "stock" with Honda Power-Up Kit tuning. This popular "uncorking" of the engine's jetting, induction system and exhaust have each been covered in detail at the magazine and the magazine's forums. This iconic motorcycle model has a large following, as the XR650R is the largest displacement enduro single cylinder bike built by Honda specifically to win the Baja 1000 and other open desert races. The magazine's viewers and forum members have followed the performance gains made with this engine build-up and tuning. The addition of the Enerpulse Pulstar® spark plug provided these noticeable results: 1) Since the rebuild and tuning, the engine has produced superior torque (49 lb-ft estimated) and a high horsepower output (approximately 55 horsepower). Along with the Pulstar® spark plug change, we added a 6.3 gallon fuel tank (5 extra gallons of fuel at approximated 40 pounds net weight gain between the fuel and the large tank) to the motorcycle. Testing the Pulstar® spark plug, performance with the additional weight is slightly better than with the lighter 2.6 gallon factory fuel tank. 40 extra pounds is significant for a dirt enduro motorcycle. When we reinstalled the 2.6 gallon tank for further testing, acceleration and throttle response showed noticeable improvement. Torque increased, and fewer downshifts were necessary under load. 2) A converted dual-sport, highway legal machine, the XR650R is kick start only. Tuning has enabled ready starts with a stock-type NGK spark plug. The Pulstar® spark plug fires the engine with equal ease. 3) Flooding is always a concern on a large displacement single cylinder motorcycle engine. The Pulstar® spark plug strongly resists fuel fouling. The spark plug readily fires through richer mixtures at altitude. 4) This engine has a fixed-jet factory Keihin slide-type carburetor. Altitude sensitivity is always an issue with fixed jets. Larger displacement engines are more susceptible to fuel fouling at higher altitudes. The Pulstar® spark plug, with superior spark output and more complete fuel burn, clearly maximizes performance over a wider range of altitude—even with a fixed jet carburetor. During the road and dirt testing, this motorcycle operated between 4,400 and 7,600 feet elevation with no sign of "rich" mixture spark plug fouling. The fixed carburetor jet setting is for 1,500 and 5,000 feet elevation. Clearly, the Pulstar® spark plugs burn cleaner and more efficiently, producing better power and performance at higher altitudes. Honda XR350R Motorcycle—This OHV bike is strictly set up for dirt riding. The stock motorcycle was upgraded for desert hare-and-hound scrambles, tuned and jetted for optimal performance at 4,400 feet altitude with the stock factory dual Keihin carburetors. In top condition, with normal compression and peak tuning, the only change was the switch to a Pulstar® spark plug. Our extensive testing in the high desert and mountains spans from 4,000 feet elevation to 6,500 feet elevation. A single cylinder, air cooled engine provides an optimal test bed for combustion and fuel burn comparisons. Pulstar® spark plug test conclusions: 1) Starting is easy whether cold or hot. Starts readily with the choke on. Warms normally as with the stock type NGK spark plug. 2) Throttle response is crisp and noticeably improved. Engine stability under load has improved, requiring less downshifting to compensate for load. (Watch the video.) 3) Again, the most significant gain is less sensitivity to altitude changes with fixed jets in these two carburetors. We operated the motorcycle from 4,000-6,500 feet without adjusting the carburetors or altering the jets. The motorcycle performed flawlessly. 4) This motorcycle has always been miserly on fuel compared to two-stroke engines or larger displacement four-stroke thumpers. Testing revealed a noticeable improvement in fuel efficiency. The motorcycle ran our pre-determined course under load and used less fuel-per-hour than with the stock-type NGK spark plug. This improvement can only be attributed to the Enerpulse Pulstar® spark plug. We'll continue to evaluate these spark plugs over time. They offer a significant breakthrough in spark and combustion technology. Enjoy the video! Moses
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In the 1990s, we began riding Honda XR dirt motorcycles. In the early '90s a modest $75 worth of parts invested in a Honda XR75 became youngest son Jacob's first motorcycle at age 12. Oregon friend Kirk donated two core bikes to the cause from his stockpile of old Hondas. When we returned to the high desert country at northern Nevada in 1994, my logical companion for Jacob's XR75 was a used 1983 Honda XR200R purchased from the Reno dealership. Jacob soon outgrew the XR75, and I outgrew the XR200R thumper. Jacob inherited the XR200R when I found the right four-stroke bike, a very well prepped 1984 Honda XR350R built by Rick Sorensen, a professional Airframe and Powerplant aircraft mechanic and owner of an independent motorcycle shop at Yerington, our hometown. Rick built the machine for his daughter Tasha to potentially race hare-and-hound, and she prized the machine. Tasha went to college, and while a student, she offered the bike for sale. Knowing how much energy and upgrade equipment Rick had put into this purpose built machine, I gladly paid Tasha her asking price. The bike received my respect as well, and it continued to deliver everything from bona fide desert enduro riding at speed to tight, single track trailing on the steep, off-camber switchbacks leading to mining claims at Black Mountain. The XR350R was a great teacher, its Pro-Link rear suspension, advanced forks for the era, rugged tubular steel frame and bulletproof four-valve, single cylinder engine were predictable and ample. In the day, a six-speed gearbox and advertised weight under 250 pounds had made the XR350R popular alongside its potent yet beefier XR500R counterpart. Rated 22.4 horsepower by most accounts, the 1984 engine featured some upgrades yet still maintained the progressive dual carburetors for the twin intake port, four-valve head. From a tuning standpoint, the dual carburetors were condemned by many, as this was the period when single cylinder engines commonly had only one carburetor. Although the rumor mill is rife with attacks on these twin-Keihin carburetors, I have never experienced trouble with this design. In fact, the tune that Rick Sorensen set was so precise that the only cause for rebuilding these carburetors came a decade after acquiring the machine. My rebuild had nothing to do with a deficiency in the carburetors but rather the result of leaving ethanol-laced gasoline in the bowls too long and ruining the pilot jet on the primary carburetor. I "blueprint" built and staged these carburetors, and the performance went right back to Rick's original aims. I've had several opportunities to part with this machine, offers from those who know its virtues and steadfast ability to pull off a great day's riding, anywhere and anytime, from High Rock Canyon to Johnson Valley when I covered the King of the Hammers race in 2012. Appreciation for its consistent performance and exceptional reliability has kept me from letting go of this machine, which is now relegated to occasional recreational riding since the acquisition and build of the "Big Red Pig" Honda XR650R. Our youngest grandson, Camden, now 2-1/2 years old, calls the XR350R "Little Red Pig" and the XR650R the "Big Red Pig". My '84 XR500R restoration project, while under a dry tarp at present, is nonetheless the "Middle Red Pig"—or simply "Middle". Honda XR350R Specs.pdf It's pointless to compare the air-cooled Honda XR350R to the XR650R, the latest CRF450X or KTM 350. The vintage XR350R four-valve thumper has nowhere near the power hit of an XR500R, XR600R or the liquid cooled XR650R. However, for many riders, the XR350R can be the weekend desert enduro bike with a low initial purchase price and far less maintenance cost if in good condition with a credible history. These bikes perform trouble free for years, and they wear out slowly and predictably. Parts are still available for most areas of the cycle. Used pieces or improvising are sometimes necessary. I ride my XR350R to stay in good physical condition and to maintain agility and survival reflexes for both dirt and asphalt motorcycling. Easier to throw around on dirt than heavier machines, the bike provides excellent terrain feedback and continuously works all five of my muscle groups! My most recent workout on the XR350R was a test of the Enerpulse Pulstar PlasmaCore spark plug this morning. I filmed my ride with the GoPro Hero3 mounted in a Chesty harness. The edited video default is HD 1080P, and if you have the bandwidth or can stream Vimeo on the big screen through your Roku, Apple TV, Chromecast or Amazon Fire TV player*, enjoy the scenery! (Otherwise, there's the subtler SD play option.) *Note: If you have one of these streaming players, simply do a search under "4WD Mechanix". You'll have access to the 190 videos now available at the Vimeo 4WD Mechanix Video Network Channel! If you have a smart television or large computer monitor, simply go to the Vimeo Channel at: http://www.vimeo.com/channels/4WDmechanix. The riding venue begins just ten minutes from the 4WD Mechanix Magazine office...Take a 15-minute ride with me as the XR350R ascends from a high desert elevation of 4,000 feet into the nearby mountains and wild horse country over 6000 feet. This is what desert enduro motorcycling is all about! See why this three decade old "friend" has remained my recreational dirt bike and exercise outlet for nearly twenty years now... Moses
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So, I have this Euro model XR650R project, and I acquired the bike right. As the upper engine rebuild and other restorative measures unfold, I'm starting to wonder what is a reasonable amount to invest here? The engine work and all the other parts I've bought are pushing things pretty close to $2k - and this bike can't be worth much more than that! Furthermore, I dropped nearly as much on new gear (helmet, boots, gloves, etc...) DON'T TELL MY WIFE! Cheers, David -
The Hot Cams Stage 1 cam for our Honda XR650R motorcycles sounds to be exactly what I'm after in power. In the past more power equaled more fun. That still holds true today, but to a lesser extent for me. I definitely will have to put in the Stage 1 cam if the bike shows wear in the top end anything near what yours had. It's good to know there is still more good power to be had even if I don't really need it. As far as that auto-decompressor, I only use it because that is all there is on my xr500r. It is a real pain trying to use to bump start the 500 even when it is on top of a good hill. I've been an Oregonian my entire life. I've barely moved a mile from where I grew up, but the change in population, traffic and rat race in general is extreme to the point of looking to move when I retire. I love Eastern Oregon, friendly people, beautiful country, you live in the outdoors. There are drawbacks of course or everyone would be moving there. All of my riding in Eastern Oregon is in conjunction with camping, which was in the vicinity of the Strawberry Mtns this year. I look forward to doing more exploring of the Steens and even the more remote Trout Creek Mountains someday. We generally ride out there on the remains of old jeep trails, roads that are no longer on any modern maps and sometimes I use Google earth to look for ways in and out of certain areas. My son led us into one area last year where we didn't get our bikes out for 3 days. We had to hike out cross country (I have a good sense of direction) for over 12 miles much of it as the crow flies, getting back after midnight. That was a bit reckless and won't happen again. I used the remaining bike at camp to explore an alternate route coupled with quite a bit of hiking to get the bikes out. Western Oregon as you know is a completely different climate and very different riding. We rode in the 70's out in the Burn, now the Tillamook Forest. Where we used to run in the Trask is now gated since Weyerhauser bought out Willamette Ind holdings there. We ran a lot where the Trask Mt ISDT was held, and would seldom see another rider. The best riding I ever experienced. I'm not sure where to go now. I'm trying to get 2 of my old riding buddies to ride again, One of them has an 80's TT600 and still rides occasionally, and may know of some good areas and the other still has his TT500, but hasn't started it in a very long time. Interests often change, but I will keep trying until I hear a no answer. I have never ridden the dunes, but my stepson who is into quads has been asking me to come. It is not close and finding that much travel time has not been easy. I'm interested in what you find when you dig into the 84 XR500R. It has a totally different engine than my 82 model. Did you know the 82 xr500R has a reed valve? I have been experimenting with the rear suspension on my XR500R. I've given it more sag and in doing so lowered it quite a bit. It was sprung too stiff for my weight and while much smoother than the ol BSA, I think I can make it fit me better with some tuning, but I will sacrifice some comfort for good trail riding ability. The reason I went with the 82 xr500r over the 84 XR350r was the over heating factor. I was afraid I could burn it up on slow trails in the summer heat. It has adequate power and a much better front brake, but I thought better suited to running fire roads to keep air moving around the engine. I should look into jetting but it does run smooth. I don't remember if I ever checked the plug. I'll have to do that. You can smell the heat coming off the engine when every other bike with us is normal. Greg -
At the forums Garage Photo Gallery, member "FullChoke" (Greg) responded to my photo of the magazine's 1984 Honda XR350R motorcycle. We have identical '84 XR350R motorcycles. Greg's cycle has engine heat-up problems, and this raises the issue of how to keep any air-cooled dirt or dual-sport motorcycle engine running cool enough. I'll begin with sharing our exchange at the Garage (below), followed by pointers on how to keep an air-cooled dirt or dual-sport engine from overheating. ************************************************** My comments at the Garage Photo Gallery: Moses Ludel 23 September 2013 - 02:33 PM The Honda XR350R cycle has been in our stable since the late '90s. Rick Sorensen, an A&E aircraft professional, had set up this dirt motorcycle for desert enduro riding. Rick's attention to detail, tuning and appropriate upgrades has made this one of our favorite dirt motorcycles to date. When new, the 1984 XR350R came with many advanced features, including Pro-Link rear suspension, a disc front brake and the four-valve, twin-intake and exhaust thumper engine design. The performance, dependability and flexibility of this engine has been a constant source of satisfaction. Under the most challenging conditions, including crawls through milder "rock gardens", the cycle and four-valve engine have delivered tractor-like stability. In other online forums, there is much talk about the "failure prone" and "problematic" dual carburetors on the XR350R and XR500R engines. In my experience, nothing could be further from the truth. I have rebuilt these carburetors and set them up to factory specifications, adjusting linkage and cables accordingly. The dual 26mm Keihin carburetors are stable and flexible enough to get by with the same jetting from Johnson Valley (King of the Hammers) to timberline at Nevada's high mountain ranges. Note: I jet for our base at 4500 feet elevation. The carburetors tolerate short rides to 8,000 feet and drops to 2,500 feet. That's very flexible, and though I would re-jet for extended riding at either of these high or low altitude points, these carburetors will "function" over that range. Simply put, I'm not fiddling constantly with the carburetors. The transition to the secondary carburetor is seamless, and by making sure there are no vacuum leaks, the tuning stays rock steady. Sure, EFI delivers more power and refined tuning, but these twin Keihin 26mm carburetors do work well and can be adjusted, or even re-jetted with care and patience, when you're 120 miles from a paved road. As for handling, I always ride the motorcycle that's under me. Sure, a CRF450 or XR650R could "run circles" around these earlier XRs, but that's not what I'm riding here. The XR350R can provide a great ride when handled like, not surprisingly, a tuned XR350R and not a CRF450. This logic applies to road cycles, too. I never rode our Honda Gold Wing or the BMW K1100LT like I did my two 1969 BSA motorcycles, the lightweight 650 Lightning or the 750 Rocket III. When I hopped on my youngest son's Yamaha YZF600R6 a few years ago, that was a different story as well. For this XR350R workhorse, I'm considering a dual-sport conversion kit from Baja Designs to enable highway access. We have an '84 XR500R waiting in the wings for restoration, another dual-sport candidate. Each of these bikes would weigh under 300 pounds converted, much nimbler on dirt than a KLR or BMW in any form. Nevada's new OHV permit program makes it just as sensible to opt for a DOT-standards conversion and license ("plate") an XR for dual-sport use. We carry insurance either way. On that note, expect details shortly on what direction this takes. If the dual-sport conversion route, I'll cover the steps at the magazine in an HD video 'how-to'. Moses Greg's comments at the Garage Photo Gallery: fullchoke Yesterday, 09:22 PM The1984 xr350r has a history of running hot and burning up. I think that was blamed on the new head design and the 2 carb system. Possibly the overheating could benefit with richer jetting. I know mine gets hotter faster than any bike I've owned. I haven't run it much and when it is used it has been a buddy's bike, usually run fairly slow. When compared to other bikes running over the same terrain it is noticeably hotter. For that reason I run a full synthetic oil, hoping for more protection with a higher boiling point. The front disc brake is a very nice feature, best thing about a very good bike. Greg ******************************************************************* How-to troubleshoot an air-cooled motorcycle engine overheating problem: As for overheating, let's start with a systematic troubleshoot. First and obviously, the engine cooling fins must be clean with sufficient air flow. Also, a four-stroke engine does not like to idle for extended periods in still air. This even applies to liquid cooled dirt and dual-sport motorcycle engines. (There are constant internet discussions about overheat, even on models like the liquid cooled XR650R and others.) Two-strokes with premix fuel have less tendency to overheat, though heat can still be an issue. When we ride extensively in the desert during hotter weather, I'm always conscious of air flow. After a good high speed streak or even picking through basaltic rock flows, my Honda XR350R remains "reasonably" cool. I'll let the engine idle for just a moment to help stabilize temperatures before shutting it off. We do crawl in stand-up-on-the-pegs type challenges, one location in particular is at high altitude. This engine has never reached critical temperatures. Your use of synthetic oil can help, too. Running cool at high altitudes is in part what you suggest. Proper jetting for sea level to 4,500 feet, then running the engine at 7,000 feet, makes the fuel mixture richer. I've never fouled a spark plug or experienced blubbering or unstable operation with these richer mixtures. In my experience, jetting is not that sensitive on these four-strokes, they are way more flexible than many give credit. Main jetted for best performance at 2,500-5,000 feet (our typical high desert country), this same engine has run flawlessly from 2,300 feet on the floor at Johnson Valley, CA to nearly 7,000 feet—without a re-jet. Of course, if the engine were operated consistently at 6,000 feet or higher, I would re-jet. Keep the jetting within a reasonable range. Read the spark plug color after a hard, open throttle run and prompt shutdown! That's the main jet's realm. If anything, jet slightly rich. In current jetting, my XR350R can run at sea level without burning a hole in the piston. Again, if I were to run the length of Baja, I would jet for sea level to 4,000 feet. Never jet so rich that fuel can wash oil off the cylinder walls nor so lean that the valves and piston are at risk! Learn to read the spark plug. Often overlooked is the importance of proper valve clearance. Valves adjusted too tight will cause engine overheating and also lower compression. Unseated valves lead to valve face burnout and seat damage, too. Adjust valves to specification, and also adjust the decompression lever and kick start cables. This is a big part of maintenance on the XR350R, the XR500R and similar Honda dirt bike models. The auto-decompression camshaft design eliminates the kick starter cable on later XRs. However, the manual (handlebar) decompression lever adjustment remains very important on every one of these models. On the XR models with dual carburetors, folks need to get over the idea that these engines never run right. Actually, this myth is helpful to those of us who value the dual-carburetor era, Pro-Link models—you can buy them at bargain prices! A common mistake is for the carburetors to be sync'd improperly. There is a very clear adjustment here, which I can share if necessary. Be aware that these carburetors do not open simultaneously! The linkage is actually "progressive", with a lag stage as the primary carburetor provides a smooth idle and light tip-in air/fuel flow. Then the secondary carburetor (which has no idle mix screw) comes into play. Think of this like an automotive engine with a progressive four-barrel carburetor or multiple carburetors. Adjust the cables and the staged throttle linkage to specification. These engines will start readily and run fantastically if the jetting, float level and needle settings are correct! General footnote: Current ethanol fuel wreaks havoc on motorcycle carburetor passageways. Do not leave the bike parked for long periods with fuel in the carburetor bowls. Shut the petcock, and with the bike upright, burn fuel until the engine stalls. Fuel standing in the bowl will clog jets, it did mine. The immediate symptom is an unstable idle and poor low throttle response. (I ended up rebuilding both carburetors after letting the cycle sit for too long with "winterized" and "Ethanol" mix fuel in the tank and bowls!) Use a fuel stabilizer additive, this can help for shorter storage. Long term, drain the fuel tank and the carburetor(s). Without stabilizer, fuel can become stale and worthless in months, depending upon the climate. Air/fuel flow and ratio are a critical part of air-cooled engine performance. Keep the air filter clean and oiled properly, whether stock type or aftermarket. A clogged cleaner element will make the engine run rich or stall, much like leaving the choke on. Also, when considering a lean fuel mixture, always take air leaks into account. Air leaks on the manifold side of the carburetor(s), between the head and carburetors, can lean out the fuel mixture. Check for leaks at flanges and junctions. Using a can of spray carburetor cleaner or WD-40, spray a fine mist at flanges with the engine idling. This can quickly turn up an air leak as the engine speed flares up or changes. Avoid spraying at high heat areas that can ignite the spray! Once you've worked through the intake side, make sure there are no exhaust restrictions. I have a "tunable" SuperTrapp exhaust end that is set up with the right number of discs for proper backpressure. I periodically remove the disks and gently bead blast the carbon away to keep tuning accurate. Improper exhaust backpressure or clogging can be a major source of overheat on a motorcycle engine. After fuel mixture/jetting, carburetor sync'ing, air leaks and exhaust restrictions and tune, there is the ignition spark and timing. Of course, spark must be adequate, and the spark plug should be the correct heat range, especially on an air-cooled engine. A "hotter" plug can be serious trouble if not in place for a good reason. Hotter spark than the stock Honda ignition (in good condition) is rarely necessary. Note: The compression ratio is higher, so you also need to run better octane fuel, especially at lower elevations. This may not be true for high altitude. I can run 87-octane in the XR350R at 4,000-8,000 feet because the atmosphere effectively lowers the compression ratio. I am not as flexible with the Honda XR650R at 10:1 compression and a bore size within 0.060" of a 327 or 350 cubic inch Chevy V-8! If you're at a lower elevation with high compression, spring for 91-92 octane fuel. This helps prevent detonation/ping, overheat and stress to the engine. For an XR500R, XR600R or XR650R, I would run 91-92 octane all the time. The last item on our checklist is spark timing. Either retarded or over-advanced, spark timing error can kill a motorcycle engine. Check the spark timing from idle to full-advance at speed. Make sure the timing advance is set properly. You can test with a conventional timing light or a light with built-in advance, this is not rocket science. I can help cast light on the procedure and expected results. With an electronic ignition, spark timing either works or it does not. If a motorcycle is old enough to have a mechanical spark advance mechanism, like our BSAs of yore, a sticking or defective spark advance mechanism can cause overheating as well as performance problems. Of course, there are overheat causes unrelated to the engine, like too much friction in the gear train or binding brakes (a sticky front or rear brake caliper, brake shoes dragging or warped/defective rotors and drums). Wheel bearing resistance, low tire pressure or chain drag can also overheat an engine. Check for resistance with the motorcycle wheels and tires lifted safely off the ground or floor. This is a place to start, and I am happy to continue this discussion. Glad that FullChoke triggered this topic, that's what these forums are all about! Moses
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The burgeoning interest in overland motorcycle travel and dual-sport conversions has many incentives. Aside from the relatively inexpensive nature of motorcycling when compared to four-wheeled travel, there is also the unique sensation of open-air, two-wheeled adventure, traveling overland to far away, dirt road places...Every dual-sport enthusiast has his or her idea of the ideal motorcycle adventure. Mine happens to be twofold: the Himalayas (specifically Bhutan, Nepal and Tibet) or Mongolia! Oh, then there's also the Silk Road... To even consider such a grand scale trip would require solid planning and the right equipment. Motorcycle stowage space is limited, and fuel is scarce at distant places. Fuel capacity is always a concern, often remedied with an aftermarket tank during a dual-sport conversion. Camping gear must be compact, light in weight and effective. Despite space limitations, your physical needs will be the same. Quality, life-preserving equipment is the order of the day. This forum community is for those of us earnestly outfitting for long distance travel to remote places. Even shorter jaunts across a remote mountain range, a desert like the Mojave or Black Rock, Death Valley, Central Nevada or whatever, requires provision for the temperature extremes in an arid climate. I've lived at high desert and higher altitudes the majority of my life, so temperature swings of 40-degrees F or more in a 24-hour cycle are not foreign. I've worked outdoors at -20-degrees F with wind chill added from there. I know what materials are life saving in extreme cold—whether running heavy equipment at Winnemucca in December or riding a motorcycle over the Sierra in the late fall or spring. Enjoy this Dual-Sport and Dirt Motorcycle Equipment Forum, it's a community where we can all share our enthusiasm and insight for safely and practically traveling to remote places!—Moses Ludel
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Building a motorcycle engine for reliable performance begins with careful assembly work. The Honda XR650R project came under the close scrutiny of an HD video camera, and the result is the 49:37-minute streaming video rental at Vimeo On Demand. Following the build, proper break-in of the engine is crucial. During assembly of the XR650R top-engine, care was taken to lubricate critical parts for the initial engine startup. This included lube on the piston pin, rings, valve stems, camshaft, valve tips and timing chain—as illustrated and detailed in the video. Lubeguard Assembly Lube, Permatex Ultra-Slick Assembly Lube and Lucas break-in oil with zinc were each used accordingly. The importance of zinc additive during break-in cannot be overstated. When a cylinder has been honed precisely like the work performed at L.A. Sleeve Company, piston ring seating is less of a concern than the camshaft break-in. Ring seating is still important, and I will describe my technique for ring-to-cylinder wall break-in: To begin, I use a non-synthetic oil that will provide enough friction to actually seat the rings. Synthetic oil often has too much of a protective film to allow necessary friction. After break-in, I will change to full-synthetic oil and dramatically decrease ring wear by providing an extra friction barrier or film between the cylinder wall and rings. Ring seating can be dramatically enhanced by smoothly accelerating the engine and decelerating the engine. Heavy throttle for sustained periods should be avoided for an initial timeframe (at least an hour of operation or 60-100 miles of road use). When you decelerate the engine, the piston rings push out against the cylinder wall. As noted in the video, the top compression ring for the Honda XR650R has a gas ledge machined on its upward facing, inside edge. This raises ring pressure against the cylinder wall, especially during acceleration/deceleration cycles. This increased pressure quickly seats the rings. Caution: A sure way to prevent rings from seating is repeated hard acceleration without any deceleration cycles. Gradual acceleration, limiting peak rpm and regular deceleration cycles get the best results. Camshaft break-in is highly significant. Damage to a new camshaft's lobes during break-in can occur quickly. The absence (deletion) of zinc from current motor oils has made this issue even more critical. (I discuss this at length in response to a Jeep 4.0L flat tappet camshaft and oil question here at the forums, read that information at the topic link.) On the Honda XR650R engine, an aftermarket camshaft from Hot Cams came with very specific instructions on initial startup and break-in. I include those concerns in my camshaft startup and break-in approach: During upper engine assembly, Lucas break-in oil with zinc was added to the oil (poured over the camshaft) prior to startup. The amount used was based on the product's instructions, and I reduced the quantity in proportion to the quantity of oil in the Honda XR650R lubrication system. At the first startup, the engine was run at 2,500 rpm immediately after picking up oil pressure. On the motorcycle lift and strapped upright, the motorcycle's engine was cycled between 2,500-3,000 rpm with a large electric fan in front of the cooling radiators for the first 20 minutes before idling down to 1500 rpm. (I used an infrared thermal gun to monitor cylinder, head and exhaust header heat this entire time.) After the initial 20-minute run on the stand, the initial road/trail miles involve a cycling speed between 1400 rpm (idle) and an estimated maximum of 3,500-4,000 rpm (no tachometer on this dirt bike). I run for 20-30 minutes at a time, varying the road or trail speeds, then cool the engine completely before repeating the cycle. Make sure that your lighter on-road or on-trail use provides sufficient cooling air to the radiators and cylinder. Earlier morning or cooler evening rides are helpful. Avoid idling for extended periods, and avoid over-revving the engine. I avoid redline shifts for at least the first 100-150 miles or 1.5-2 hours of operation. Considering the operating speeds for a four-stroke motorcycle engine compared to an automotive engine, three hours (approximately 200 miles) of concentrated effort to break-in the camshaft properly should be sufficient. Rings should be sufficiently seated now...At this point, the oil should be drained warm and thoroughly; I switch to synthetic oil now. Note: During this oil change on the XR650R engine, I will remove the frame (down tube) oil screen (not the inside-engine screen) for inspection and cleaning. A new oil filter is mandatory; inspect the removed oil filter for unusual debris. In the road test video, I'm on the throttle but not redlining. I don't baby (never "lug") or abuse (do not over-rev or throttle hard) an engine during break-in. Constantly monitor engine temperature and avoid overheating or extensive idling. The Honda XR650R showed no signs of "blue smoke" (ring blowby or valve guide seepage) from the very first start onward. You should not see blue smoke or significant oil consumption if the cylinder has been honed properly, the rings were installed correctly and the valve guides are sealing. By 200 miles or 3 hours of operation, a motorcycle engine should have sufficient break-in to no longer be a critical concern. As long as oil consumption (ring blowby) does not occur with the switch to synthetic oil, the engine is ready for reasonably "normal" use—whatever that means for your riding style. For the properly built engine, with correct break-in, a quality synthetic oil will determine the lifespan of the rings, valve guides, timing chain, camshaft, rocker arms, engine bearings, piston/pin, and other critical moving parts. Wear is greatly reduced by the use of synthetic oil. Unlike an automobile or truck engine, wear will be much more significant on a motorcycle engine that operates consistently above 3,000 rpm. Wear is all about piston travel and valve opening events, and synthetic oil can make a difference here. Moses
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I pulled the oil filter and passed a large magnet over it but I did not pick up any ferrous metal. The close up photo of the filter reveals many small chips of aluminum. Well all I have to do is open up the motor and start looking for a bright shiny spot! This is the filter out of the 2006 salvage bike. -
I bought this 2002 KLR engine from a listing in craigslist for $100. The previous owner stripped out the oil drain plug threads then attempted to use a tapered bolt that spread the stripped threads and cracked the engine case. I have another set of engine halves. I could transfer parts from this damaged engine into the good case halves, but I was wondering if this case could be repaired as it sits? I'm pretty sure that the case is made of cast aluminum.
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As you might guess by now, I also ride dirt motorcycles—a lot! Our Honda XRs have been terrific desert and single track bikes, my style is desert enduro and slower-speed rock maneuvering. Nevada has enacted an OHV "permit" program for ATVs and dirt motorcycles. By July, its an annual permit on the off-pavement motorcycles or converting either my Honda XR350R or XR500R to a street legal dual sport with a license plate and insurance. With the dual-sport approach, I've considered upgrading to either a converted XR650R or a current factory dual-sport. I am steering away from the weighty adventure-touring motorcycles, I'm after a legitimate, lighter weight dirt motorcycle platform. Poking around, I like the KTM 350EXC and 500EXC, though each comes with severe MSRP sticker shock. The Christini 450 DS also caught my eye. The Christini chassis hosts a powertrain and chassis with a strong resemblance to Honda's CRF450—add to that the patented and competition-proven Christini AWD system. Yes, that's two-wheel drive for a motorcycle! Rave reviews and competitive laurels include the successes of Geoff Aaron in brutal off-road races like the Iron Giant and Wally Palmer taking on the XGames at EnduroX and MotoX Step-Up! Less known is the Christini DS, a 49-State legal motorcycle for dual-purpose, street and off-pavement riding. At 288 pounds, with this kind of power, AWD and a competition-proven chassis design, the Christini may well be my choice. (See the Christini cycles at www.christini.com.) Stay tuned, all-terrain is my thing whether a built-up 4x4 Jeep Wrangler Rubicon, our XJ Cherokee with 6-inch long arm lift suspension, a vintage FJ40 Land Cruiser with a 383 stroker V-8, a rock buggy, or on a dirt motorcycle—two driving wheels on a moto? Wow, you'll want to know more about this one! Expect ongoing updates here. The magazine has committed to more dual-sport and OHV coverage, and my personal angle is dual-sport desert and overland motorcycling. Whatever cycle I choose, expect 1080P HD video coverage. Yes, the goal is way more off-pavement destination four-wheeling and motorcycling. Stay tuned at the 4WD Mechanix HD Video Network! As this unfolds, expect updates and helmet cam views from the single-tracks...Join this forum, and let's share our experiences with dirt and dual-sport motorcycles!—Moses My XR350R has been a workhorse! I used this bike to cover the 2012 King of the Hammers Race at Johnson Valley, California. This cycle has been my primary desert bike since the mid-1990s. I also have an XR500R. Both the 350 and 500 are 1984 vintage with Honda's Pro-Link suspension, still a functional design to this day! An XR650R would be a nice alternative for a dual-sport conversion.
