Read more about Ask MO Anything: Is Clutchless Shifting Bad For My Transmission? at Motorcycle.com.Yes, it’s all true. Well, it kind of depends on your bike. Some motorcycles with great big flywheels and big gears, like many Harleys and some BMW Boxers, need the clutch – or at least a little clutch – for nearly every shift. Most sportbikes only need you to use the clutch to pull away from stops and for the shift from first to second gear.
At slow, around-town speeds, we mostly use at least a little clutch to shift anyway; you don’t need to pull the lever all the way in every time you use it. But if you’re steadily accelerating, and especially at WOT (wide open throttle), you’ll find that after second gear, if you roll the throttle closed just enough to unload the driveline, for just a split second, with your toe pressing on the lever, then third gear will slip right in without using the clutch at all. Fourth, 5th and 6th will slip in even easier since the gaps between them are increasingly smaller. Done smoothly, it’s no harder on your gearbox than using the clutch.
Damage occurs when loading is not reduced adequately for the dogs to disengage the old gear then re-engage the new gear.
When you take your hand off the throttle while accelerating your clutch automatically engages somewhat not all the way. So shifting if you time it right without a clutch is quite all right. You can upshift and downshift if you get the synchrony together. What can happen is if you forget what gear you’re in and you shift it down too fast or up to slow you’ll either over or under rev the engine which is bad for it! originally manual transmissions the driver had to match the road speed versus the engine speed to shift into gear‘s. If this doesn’t happen it does not matter because the transmission will not allow you to shift into that gear. Synchromesh or constant mesh eliminated that variable so that you could shift into fifth gear and be going 10 miles an hour or first gear and hopefully not going 50 mph!