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Is the R3's engine braking pretty standard for a motorcycle?

11K views 15 replies 14 participants last post by  xorbe 
#1 ·
For all you veteran riders / engineers out there...

I've only ridden a couple different bikes, so I don't have a whole lot of experience to judge.

I understand the bit about slowing a bike down with downshifting. But I find that even if I let off the throttle without shifting, the bike slows down quite a bit on its own. Is this pretty standard? I've seen some comments that the R3 has particularly strong engine braking.

So engine braking just comes from the cylinders trying to work against a closed air intake? Is the level of braking something that can be adjusted? Or I imagine it's a pretty integral part of the engine design?

What is it about motorcycle engines that make them so much different than car engines? Is it just engine volume relative to the weight of the vehicle? On my stick shift car, laying off the throttle just lets me cruise easily, without any feeling of engine braking.
 
Discussion starter · #9 ·
Thanks everyone for the great explanations, especially Stirz for all your good guidance along the way.

Now to get into the weeds of engine design...

So on the R3 or (fuel injected) motorcycles in general, when you lay off the throttle not only does the fuel injector stop, but the air intake gets closed off completely?
And this is why engine braking is so pronounced on a motorcycle, along with the engine displacement / motorcycle weight ratio?

As best as I understand my carbuerated Ford V8, all it's got is a choke plate. Once that is open, there's nothing to regulate incoming air flow. Power to the engine is therefore determined only by how much gas is squirted in by the throttle cable, or drawn into the cylinders by the venturi effect. So no closure of the air intake, and thus less engine braking?

Half the fun of cars or bikes is understanding the mechanics, at least for me.
 
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