[akima]

Useful thread. These 3 posts seem quite reasonable to me:

Originally Posted by Alex

I don't fully agree with the OP's distinction between "Engine Braking" and "Down Shifting" definitions. Engine braking may or may not involve downshifting. All engine braking means is that the rider is applying less throttle than would be necessary to maintain a constant speed, typically no throttle at all. The friction between all of the engine's moving parts slows the engine and in turn the bike, as the rear wheel is still directly connected to the speed of the engine, even when it's not under power.

The lower the gear, the stronger the engine braking as the torque of the engine friction is multiplied by a higher ratio. I.E., if you are at 60 mph, engine braking in 4th gear will slow the bike faster than if you slow from 60 mph by engine braking in 6th gear. That's the reason why downshifting can be helpful, as in a lower gear the technique is more effective.

It seems your question is basically making a distinction between whether or not to match revs while downshifting. In a perfect world where one would try to make the downshift as smooth as possible, and limit clutch wear as much as possible, it would be appropriate to match revs until the clutch is engaged and then to once again let off the throttle completely as the bike slows. But in terms of a practical answer, it's probably not necessary much of the time. Even with the throttle completely closed, downshifting and letting the clutch back out will speed up the engine to match the rear wheel speed very quickly. Our engines are so small, light, and easy to rev, that it would be hard to do much clutch damage by intentionally slipping it on these types of downshifts. Clutches on these bikes pretty much last forever.

Originally Posted by tjkamper

Engine Braking is letting the Engine slow the vehicle down. In cars overdrive is used to limit this effect. Technically you do not have to downshift to be engine braking, but the higher the gear, the less you will slow down. If you go through all the gears and are not flying like bat out of hell toward a stop light, you can come to a nice easy stop without ever touching the brake controls.

Matching Revs when down shifting. These engines are small and they match the wheel speed really fast. I don't think there would be any problem with not matching revs. I match reves whenever I can, but is some situations it is not possible to blip the throttle, because you are also applying heavy front break.

Not matching revs can have some adverse effects. If you have a large engine that does not match wheel speed well you can find yourself in a rear wheel skid. (My International Harvester would always do this). Also this does place a lot of torque on the clutch which can cause it to wear out faster.

However like Alex said, these bikes have such a small engine that it matches the speed very quickly. I have never lost traction from not matching revs on the ninja. Also I have heard that the clutch on this bike is vertually indistructable, because the little 250 engine does not put very much torque on it.

The most prominent benefit of Matching your Revs when downshipfting, is a smoother transition form the high gear to the lower gear and for on the street and as much as most people ride, that is all they should worry about.

Originally Posted by CC Cowboy

I use the brakes to slow down! I use the engine to speed up or cruise. I only shift when I have to.

When I'm braking to come to a stop I tend to change down a gear almost instantly using rev matching then let the engine slow the bike. When I'm getting closer to where I want to stop I then use progressively stronger front braking to shave off most of the remaining speed over a short period of time. I'm only going ~10MPH at this point. Before coming to a stop I shift all the way down to 1st gear with the clutch fully disengaged while gently applying the rear brake to smoothly come to a complete stop.

I'd be interested to hear peoples opinion on my method. It seems to work for me. I've never lost traction, held up traffic behind me or lost balance while doing it.