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2008 Dear VTwin Mama, Dear
Jenny, I admit I'm a bit perplexed about the downshifting mph ranges the owner's manual suggested. I guess what happens when one becomes experienced is that you listen to the engine rather than looking at the speedometer. For instance, when you are at a dead stop and begin moving forward, you are most likely listening to the engine sound to clue you in for the next gear upshift, right? That's a natural thing as most of use are in tune with the sound, even before we begin riding ... we hear manual cars upshifting all the time around us! In downshifting it's a bit dicier but the main point is that we're looking to maintain control of the bike at all times ... this includes smoothness of the approach to a stop and being able to still quickly move away from a hazardous/icky situation should it arise as we move toward the stop and are at the stop. We could simply let gravity do the job as the bike has a certain weight and as we let off the throttle, the bike will slow down all by itself without any shifting or braking what so ever! However, this does not meet our control requirement! And it would be hard to calculate exactly when gravity would bring us to the stop, resulting in some yelling from fellow motorists! Slowing down is a combination of using all the controls and there is no exact science so we're back to control! If we simply used the brakes we would arrive at our stop still in the gear we started out in, leaving us vulnerable at the stop, or quickly downshifting at the stop to get back to first. Not ideal because if a vehicle comes in "hot" behind you, i.e. out of control, you want to be in some gear under conrol (remember to leave some escape room between you the vehicle in front of you) to quickly move away. In addition, most bikes are designed to downshift with some motion still happening, and there are some models that can really be hard to shift at a dead stop ... you literally have to rock the bike forward and backward to get that next lower gear to click in! Remember the sound we talked about before? Here's the deal on downshifting. So, I'm probably going to let off the throttle and bleed off a bit of speed with the brakes. Then I'm going to downshift once, but here I'll be letting that clutch out just to the edge of the friction zone (where the clutch starts engaging the system) and determine if I'm still too fast for that gear (I can feel and hear the action of that engage point) ... just right, let out the clutch fully so the gear begins slowing down the bike; too high and I'm going to bleed off more speed with the brakes before engaging that next lower gear. The throttle becomes my "fine tune" as I can add or subtract a little as needed. Gauging the distance to the stop then becomes the combo of a bit of braking and downshifting, approaching the last part of the stop in second gear (so I still have getaway power) and then with just a small amount of forward movement, going to first. On my bike I know I can click into first at a dead stop, so often that's what I do. Practice of course is the key to control, so finding a big empty parking lot is a good idea, or, if your neighborhood street is a safe environment, that would work also. Get up into third with a stop point you can clearly see, bleed off a bit with the brakes, downshift but use that clutch to feather the engagement, etc. One caveat ... brakes are always used gently ... in combination or just the front one when you're approaching a stop in a straight line. If you have to stop on a curve, a gentle use of the back brake only is best. Quick stops are best handled in a straight line. If you've put in your practice time, you'll have an idea of how quickly you can stop just using the brakes; you can also practice how quickly the bike can stop by braking and downshifting so that the engine aids in the stopping power. If you are in a curve of any kind, your first determination should be whether you have enough room to straighten up the bike and enough room in that pathway to stop upright rather than at a lean angle. Brakes should be never be grabbed at or jammed on. It can lock up the system, putting you into a skid. Is a skid ever good? Well, one could argue that if an object appears in front of you so quickly that your only choice is to lay the bike down or ram head first into the object ... the skid/laydown could potentially be less physically harmful, but that's a split second decision that no one can predict. Gears wear out just for the fact that it's a material subject to wear and tear. What wears out gears fastest is constantly running the bike at the top end of their range. Lack of maintenance can hurt also, as oil breaks down as it gets older, so don't neglect those oil/oil filter changes at the recommended intervals. So, unless you're racing around like a mad woman, your gear set will handle the normal range of riding just fine! – Mama Thursday, January 10 For Jenny who has questions about downshifting correctly: Down shifting? That gun is loaded for bear. That is a great question and really is a matter of all inputs, just like Petra has said. It also comes down to your own comfort level with your bike, bike size and conditions on the road. Is it wet of has rain just started to fall? That is THE most dangerous time to be looking for stopping power. It seems as if the road is actually more slick than if it were soaked. There is a reason for that... there is just enough moisture to get between rubber and the road but not always enough to squeeze out as if the road were really, really wet. It seems like that can't be the case when you look at science but it is my experience that tells me to slow down a little and keep distance from traffic in front of me. Never, EVER cheap out on tires. Buy the tires that reflect the way you ride. A good medium compound or a little tougher is a good choice for MOST riders and will hold up pretty well in most conditions. I use a Dunlop Qualifier on the rear and a Sport Elite on the front of my old Yamaha. I used to run Pirelli's but I am older now and no long have the same need for speed but I want control. The best way to learn to downshift is very much as Petra has suggested. Go out and try it. You might find a quick shot of gas as you down shift will rev the engine enough to catch up with the now faster turning lower gear. You master this little trick and you won't get that hard clunk and the engine seeming to over rev once you let the clutch back out. Can down shifting hurt the transmission? Possibly if you abuse the bike. It is, as stated by Petra, a balance of all controls first and fore most. The great part of this way of slowing is that the rear wheel always stays turning. Is that a good thing? YOU BETCHA! Think about the commercials that show a car's anti lock braes working...the tire sort of stutter stops and lets the driver stay in control and all the while... the wheels slow the car. Downshifting is the grand daddy of anti lock. Use the engine to assist in slowing on hills and in the wet and in corners ( ONLY WHEN YOU FEEL COMFORTABLE WITH THE PROCESS! ) and you will again experience the coolness that is control over your motorcycle! A motorcycle is an extension of all your skills and as you get more time in the saddle... you will get more skill. We all had to crawl before we could walk and walk before we could run and this is no different. This is a driving experience on so many levels and you won't get it in any car, anywhere, anytime. Period. Love the site, Petra. – Ken, Biker Radio Magazine (note from Mama: thanks for expanding on the subject matter to include weather conditions and tires ... the first can be purposefully practiced as well and the second is well worth a lot of research time. I agree that the process takes many road miles and techniques should only be expanded on when the basics are first mastered.) Thursday, March 6 Dear VTwin Mama, Dear Katie, If the reach distance is ok, but the controls are a bit higher than your new hand position, you typically can undo the handlebar clamp and rotate it down a bit. If the distance and height are just fine, then check your wrist angle. Put your hands on the control ... your wrist should not be at an angle of any kind ... each control can be loosened and rotated for a better overall fit. If the distance is in fact farther than comfortable, a pullback riser insert can bring the whole assembly back towards you ... check with a dealer to noodle this out further. After these adjustments, or determining all is well, then there are several products to consider. One is a Throttle Rocker, which attaches to the end of the throttle grip, which allows your palm to take the weight of the throttle action ... I love mine! There is also a Throttle Boss, but that has a smaller area to rest your palm in. You might also check into a throttle lock for longer distance cruising ... I'm not a fan of locking the throttle cable into position, but for some, it makes a huge difference. For the clutch hand, I'd check to see how much effort you have to make to pull that in. If it's a stiff action or wide grip, there are ergonomic solutions that will reduce the pull effort by as much as 50%. Again, the availability is by make/model, so ask the Parts Department of your local dealer to determine what's what. I wish you well as you contemplate possible changes ... I'll be contemplating my navel, but that's neither here nor there in the overall scheme of things! – Mama Monday, March 24 Hi VTwin Mama, However, I was told that holding down the clutch causes excessive plate wear. I don't see how this is the case because I'm not moving, so it doesn't seem like I'm causing any friction. I prefer to shift down to first and leave my left hand on the clutch, but I don't want to wear out my plates excessively. Can you tell me what I should do/if this really does wear out the clutch? I was also wondering whether I should press the clutch down fully each
time I downshift or upshift, because it seems like most of the time I only
need to push down around 1/3 of the way. Is this "slipping the
clutch?" If I want to cause the least wear possible, should I press
the clutch down all the way or can I keep doing it the way I'm doing? Dear June, The majority opinion on this site has been that staying in 1st gear at a stoplight is the safest thing to do, because, as you note, if something awful is happening behind you, you have a chance of moving out of the way. Of course part of this equation must be that you always stop far away enough from the vehicle in front of you so that you can do a jog around if needed. I'll concede that at a longer city traffic intersection, where I know the extended length of the light change, I'll bump into neutral to wait it out. I suppose I'm still subconsciously listening for any squealing of tires way behind in the vehicle line-up, but who is to say if I would have enough time to jump to 1st and get out. This though is the reason that I tend to leave my hands at the controls rather than bring them down to my lap and that with both feet firmly on the ground, I can shift weight to hit the shift lever fast. Not perfect, but a reality. Now let's turn our attention to the clutch action. From The Essential Guide to Motorcycle Maintenance by Mark Zimmerman, "the major parts include a clutch basket, several drive and driven plates, a clutch hub, a release mechanism, clutch springs, and a pressure plate." With me so far? Most motorcycles have what are called wet multi-plate manual clutches, meaning they are bathed in oil, and while there may be more slippage possibilities than a dry clutch, there is also less friction overall. "When the clutch lever is pulled in, the clutch lifter mechanism presses the pressure plate through the lifter plate, resulting in a gap between the disc and the plates. When gradually releasing the clutch lever, the pressure plate begins to press the disc and plate by the tension of the spring, and the disc and the plates begin to transmit power by sliding contact and the vehicle will start to move. When the clutch lever is completely released, the disc and plates are completely caught between the pressure plate and the clutch center, and no longer mutually shop. The power is completely transmitted to the rear wheel." Yikes, so what does that mean in layman's terms? The question really becomes, what's the wear difference, if any, between being in neutral and sitting in 1st gear with the clutch in? Mark's email answer: "When the bike is idling with the clutch pulled in there is some slight additional wear placed on the release mechanism and clutch pressure plate and in some cases (primarily older vintage bikes) the clutch can overheat due to friction between the drive plates, which keep spinning, and driven plates, which are stationary when the clutch is disengaged. However, wear is minimal and no cause for concern where modern bikes are concerned. However, when I was learning to ride I was always taught that you never, ever stopped a bike in gear and held the clutch in because if the clutch cable breaks, and you were idly revving the throttle as many riders do, the bike would shoot forward into traffic. I understand the MSF now teaches the opposite, that you should stop in gear so that if an emergency arises you can scoot your way out of trouble. Bottom line ... stopping in gear and pulling the clutch in won't hurt a thing." So, there we have ... yes, there is an affect, but it so minimal that one can easily disregard it. Hopefully as well, you can see that pulling in fully and releasing the clutch lever fully is truly appropriate. One only stays in the middle friction zone to gain some control around slow turns or when creeping a bike forward in heavy traffic so that feet don't have to go down for a stop every few seconds. In this case you are slipping the clutch, meaning you're changing the dynamics of the plate friction and one only uses it when necessary. – Mama
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