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Kick/bump Starting Electric Start Motorcycles
#1
On 3/28/2006 Eric Stoskopf posted the following in a bug-out bike thread and ML's response seemed worthy of adding to the FAQ section.



Even though the electric start feature on the XR-L is very handy, there have been a couple times when I couldn't get the bike to turn over. I could however get the bike to start using the old bump starting method (running along side, jumping on, and popping the clutch). I still can't place a finger on why the bike is finicky when I try to re-start the bike after I've been riding. It's only occured in the last year or so. Perhaps it's time for a tune-up.



The starting issue has caused me to look at the problem from a different angle, one that may add a bit for usefulness to the XR-L and other electric-start-only bikes.



Bump-starting a bike on pavement is one thing but having to do it on a trail (dead battery, etc.), to me, would be nearly impossible. My question is this. How easy would it be for a skilled mechanic to add a kick-start lever (and other parts) to the XR-L as a back-up way of starting the bike?



I noticed two areas on the left engine casing (just above the rear brake lever) that may have, at one time been where a kick-start lever was installed before the electric start models were introduced.




ML's response:



Funny Mr. Stoskopf should ask this question. (And even nicer to see him making more frequent contributions here.)



This conversion answer is going to be pretty specific to this machine, although I’ll try to include enough other material for it to be of value to others, too.



Honda’s XR650L is an excellent street-legal dual-sport motorcycle that is electric-start only (that is, it has no kickstarter). This is almost never a problem—as noted, you probably don’t lament the lack of a hand-crank on your car.



Because it has a manual transmission, should the starter or battery fail, it’s possible to bump-start the bike. Turn on the key, make sure the kill switch is in the “Run” position, put the bike in an appropriate gear (second works best for me), pull in the clutch, and push the bike. When it gets up to speed, swing your butt up into the saddle and drop down hard. As you sack out the rear suspension, let the clutch out while giving the bike gas—if the ignition system is functioning, the engine should start.



In the case of the XR/L, there are a couple of additional bits of knowledge that can make your life easier. First of all, the machine is equipped with an automatic decompression system which lifts one of the exhaust valves slightly at low engine RPM during starting—this lets the electric starter turn the engine over more easily; after all, we’re talking about a big 650cc single cylinder here, a noble task for any starter. Second, because this is such a prodigious single, should it kick back during starting, it would positively frag the starter motor and pinion gear. Consequently, Honda’s engineers have programmed the ignition module not to send current to the spark plug when the engine RPM is below (if I recall correctly) 350 RPM. This is invisible when the engine is running, since the 650L idles at 1000-plus RPM, well above the 350 RPM cutoff. What it does do is ensure that the engine is spinning (forward) fast enough to eliminate a kickback through the starter mechanism.



These two features mean that you’ve got to push a 650L fast enough to get the engine spinning greater than 350 RPM if you want it to bump start successfully. As Mr. Stoskopf notes, on the pavement this is done easily; in the dirt, as with any dirt bike, it generally means you need to push it down hill over relatively firm ground. If you suspected that your bike might not start, make sure you pick a high point with a good runout and a firm terrain before you stop. Rule Number Two, of course, is “Plan Ahead.”



Can you retrofit a XR650L with a kick starter? I know for a fact the answer is yes. And I know it because we’ve done just the opposite: we’ve converted a kickstart-only bike to use the XR650L’s electric starting system.



That bike was the old air-cooled Honda XR600R. (Note: this is NOT the current liquid-cooled XR650R, which is also a kickstart-only machine.) The conversion can be done using only original-equipment Honda parts—you don’t have to make up anything or spend hours in the machine shop. You can’t have both, though (electric start and kick start)—it’s one or the other.



(An aside: Recently Honda and Yamaha have begun to offer 450-class machines with both kick- and electric-starting, the Honda CRF450X and CRF250X for example. As I keystroke this in this evening, I have a CFR250X sitting in my garage that I’ve been thrashing around on for the last four months, and it’s been a hoot to ride with the wet weather around here—the traction has been spectacular. And although these machines offer the convenience/redundancy of two starting systems, they are be a poor choice for the survival-minded rider. They are high-performance bikes, designed more for competition than pickup-truck-like utility and reliability. They require more maintenance, and are dirt-only machines. Mine is fun to ride, and it’s more and more fun the faster and faster you go. But sometimes you want a tractor, not a rocket.)



The electric-to-kick conversion is involved in that you have to remove the engine from the chassis, and replace the right engine-case half among other parts. So, while you could make the changeover, it would be a not insignificant investment in terms of parts and a considerable labor bill if you were paying to have the work done. Having kickstarted plenty of XR650Rs and XR600Rs in Baja on hot afternoons, I can tell you that most people would much rather have the electric=start system, even if it does add a little weight.



Mr. Stoskopf doesn’t tell us if his bike cranked but didn’t start when he had his difficulties, of if it simply wouldn’t turn over at all. Were it the first, I’d make sure the automatic decompression system is functioning and adjusted correctly. These get out of tune or wear, and occasionally cause difficulties. If it didn’t crank at all, I’d look towards (first) the starter switch itself, then the fused link and the connections to the starter motor, and finally the starter motor itself. Further directions can be found in the “Engine Won’t Start” section of the excellent XR650L Shop Manual Honda offers.



XR650Ls have been in production for twelve years now, and are as near to bombproof and thoroughly proven and understood as any motorcycle is likely to get. The steel frame is strong and easy to straighten in case of a truly spectacular get off, and can be repaired by any third-world welder with a buzz box or a gas torch in the middle of nowhere. The air-cooled engine is strong, simple, and proven, and the lack of vulnerable radiators, hoses, and pumps means you won’t have to beg your buddies to piss down some open filler neck after you’ve torn a hose off in the desert. I would, without reservation, pick this as the absolute best machine to ride on both the street and the dirt under hostile conditions, demanding trails, and for extended periods. No, they’re not as sexy as BMW’s über-cool GS-series bikes, but they’re about 1000 times more capable when that dirt road peters out into a single-track trail or a dry streambed. And I say this out of experience, because I ridden them both—plenty, in the Sierra Nevada, in Baja, in the Mojave and Sonoran deserts, and more. No, they’re not perfect (I often re-gear mine, closing up that huge gap between first and second, and lowering the overall gearing a tooth off the countershaft) and they are much heavier than a true dirt-only machine. But when push comes to shove, they’re pretty damned good, and I seldom have to say “I can’t ride up that.”



If you’re stuck in a place where it’s dead flat and the traction is poor and you need to bump-start your bike, there are a couple of things you can do. First, push or tow the machine to a more favorable piece of ground—a drag, and slow, but it may be a way out. Second, if you’re riding with a friend (as we’re all supposed to, but I at least seldom do), having the second bike tow you up to speed and then letting the clutch out (slowly!) will almost always do the trick, 550 cord makes a poor choice for tow rope; much better is a 25-foot length of flat (not tubular) nylon webbing, the same stuff the lower straps on your back pack or daypack are probably made from. It’s cheap, rolls up small, and belongs in your tool bag. The proper technique for towing one bike with another can be a topic for another day, but even the most flooded, battery-dead, cold machine will usually start if you tow it for a quarter mile to get it cleared out—and if it won’t, neither a kickstarter nor an electric starter would make any difference. Just make sure to turn on your fuel and the ignition switch first!



* * * * *



My ancient XL350R is a kickstart-only machine, and it’s part of my commuting tackle in the city. Every morning I kickstart it—one kick to prime it, then a firm boot and it lights off. But every evening, I bump-start it, just for fun, but to stay in practice two. I toe the bike up into second, roll it forward until I can feel it bump up against the top of the compression stroke, switch on the ignition, take a deep breath, pull in the clutch and then take four full steps: right, left, right, left. When my left foot hits the ground the second time, I swing up into the saddle (sidesaddle, from the left side), and the bike will start 100 percent of the time—and that’s on flat ground; no cheating! In three steps, I can get it to light off about 85 percent of the time. In two steps it’s about 30 percent. Like making fire by friction or by spark, it’s a skill, and like any skill, it’s only yours if you practice it.



Mr. S, if you’re worried about bump-starting your XR650L on a dirt road or trail, here’s your homework for the weekend. While the starter is in working order, go for a ride out where there’s some dirt. Pick a nice long downhill section with good traction, shut off the bike, and practice your bump starts. If the section is steep and long enough, you don’t even need to run next to the bike—you can just let the bike roll down the hill while you stand up on the pegs. Drop your butt into the seat and snap out the clutch—just remember (again) to TURN ON THAT IGNITION FIRST! You’ll soon find out that you can do it—I do it all the time on kickstart only machines just because I’m lazy. Just pick your stopping place in advance (that planning ahead stuff again). After that, just reduce the gradient of the hill until you can do it on flat ground. In the dirt it may take me six steps instead of four, but you can still do it with the proper technique.



Good riding, and best regards always,



--ML
Of all the things I've lost, I think I miss my mind the most.


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