- This topic has 10 replies, 9 voices, and was last updated 15 years ago by kirk.
Riding technique – engine braking
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April 19, 2009 at 12:41 am #2721WanderingRiderParticipant
I was wondering how much everyone uses engine braking vs. regular braking, and in what situations, etc?
I use it most of the time – on some rides it seems like I use it for almost everything but that final bit of braking power as I come to a stop. I’m a little concerned though if that will damage my engine, clutch, or tranny over time. Comments?
April 19, 2009 at 1:21 am #17851megaspazParticipantIt’s a tool in the toolbag so use it. Don’t rely on it soley for your braking though. Brakes will stop your bike more efficiently than engine braking.
April 19, 2009 at 1:40 am #17856MunchParticipantI only use it during down hill speed maintenance… ticket avoidance… and slowing to allow someone to change lanes. Other then that… I usually use my brakes.
April 19, 2009 at 2:53 am #17858briderdtParticipantAll the time, actually. I use it setting up for corners, coming to a stop… Just make sure that when you’re dropping down the gears you’re also dragging at least one of the brakes to light up the brake light. Otherwise following vehicles may not notice that rapidly dwindling gap…
April 19, 2009 at 4:03 am #17862SantaCruzRiderParticipantI use it constantly, though I never do aggressive engine braking that would cause the revs to get even 50% to redline.
On mountain roads, I find that I contol my bike speed almost 100% with gearing, but frequently have one finger on the front brake to give several flashes of brake light to cars that are following.
To me, worrying about wear and tear on the engine from engine braking is a bit like worrying about the fact that riding all your miles on the highway prematurely wears out the crown of your tire and too much city riding wears out the left side of your tires — just ride the d–n bike already !
April 20, 2009 at 3:58 pm #17879WanderingRiderParticipantI think with engine braking the most important aspect is clutch control. You can down shift to 1st gear from cruising in 4th, and use engine braking for your primary stopping power as long as you slip the clutch gradually, keeping the RPMS from getting too high, or locking up the rear wheel.
Like you said briderdt, you’ve got to be really careful though since your brake light won’t light up unless you are using your brakes at least a little.
One thing I usually do is flash my brake light a few times before starting braking, then hold it as I slow down (even if I’m using engine braking). I’ve noticed that people seem to react more quickly when you flash the brake light like that.
I understand that you can buy a module for some bikes that plugs in line with your brake lights, and causes them to flash automatically when braking – has anyone tried one? If so, does it seem to help?
April 20, 2009 at 5:48 pm #17885CandiceParticipantI am glad this question was asked because I was wondering the same thing. I have been using engine breaking a lot lately and as I was doing it I was thinking, oh geez, I wonder if I’m ruining my engine or something. Glad that I’m not and I’ll keep using it!
April 22, 2009 at 8:28 am #17955TerriKhaliParticipantGood question, and excellent answers.
This is such a great site to ask genuine questions… and as they say ‘there is no such thing as a stupid question… ‘
April 27, 2009 at 12:33 pm #18039eternal05ParticipantEngine braking is a tool in your toolbag, like megaspaz said, but the name is misleading. If you need strong braking forces and your brakes still function (i.e. you’re not in the 40th lap of a race and suffering from serious brake fade), you need to use your brakes. Period. That’s not to say you can’t ALSO use engine braking to slow you down that much faster, but in my opinion, the following ideology is totally counterproductive:
“You can down shift to 1st gear from cruising in 4th, and use engine braking for your primary stopping power as long as you slip the clutch gradually, keeping the RPMS from getting too high, or locking up the rear wheel.”
If you’re shifting from 4th straight to 1st, then slipping the clutch until speeds match, you are using your clutch plate to do what your brake pads are supposed to do….and that’s a horrible waste of a clutch. Your brake pads are engineered to slow down brake rotors (i.e. the “disc” in “disc brake”) by strong pressure ==> friction. Your clutch is NOT meant for that. Even if you’re shifting from 4th to 3rd, slipping the clutch, then shifting from 3rd to 2nd, etc. you’re still redirecting the responsibility of slowing the vehicle to the clutch. That’s 30mph that you’re scrubbing away quickly using your poor clutch….ugh.
Engine braking, or “compression” braking as the lawyers like to call it, is the use of the compression phase of the engine’s power cycle (i.e. the one in which the cylinder head compresses the fuel/air mixture right before ignition and the power stroke) to slow a car down. Engines do not keep spinning at a given rate unless you continually add fuel for combustion. The moment you get off the gas, the resistance of fuel/air to compression, and the friction inherent in the system will cause the engine to slow. It is THIS slow-down that is known as “engine braking.” Using your clutch to smooth out what would otherwise be a terrifically violent downshift is NOT engine braking, though you are leveraging engine braking to achieve slow-down.
So, how do you properly use engine-braking? It’s really simple: get off the gas. That’s it. Say you want to slow down from 60mph in 6th gear to a complete stop using only engine braking. You do the following (you better have an airport runway ahead of you):
1. Get off the gas in 6th.
2. When you hit the bottom of your powerband in 6th gear, clutch in, blip the throttle to match engine-to-wheel speed ratio and shift to 5th, clutch out. This should be perfectly quick and smooth.
3. Wait until you hit the bottom of your powerband in 5th, and repeat above process to shift to 4th.
4. rinse and repeat…
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N. You’re in first, going quite slowly. Eventually you have to clutch in to avoid killing the engine, and a few seconds later, you’re at a dead stop.Want to slow down a bit for a turn? Engine brake! Get off the gas, and depending on how early you start, you might lose 5-10mph rather quickly without touching the brakes or the clutch. Perfect! Going down a steep hill and you don’t want to get your speed up? Shift into 2nd BEFORE the hill and use compression braking to keep your speed down. But if you need to stop in 150ft for a stop light, do NOT shift down to 1st and scrub away your speed on the clutch. That’s just a good way to burn your clutch out, even if it is a wet clutch. If you’re riding a Ducati or some higher-performance bike, you might not even have the benefit of an oil bath…so be careful!
To answer your question, improper or excessive application of engine braking, especially via the clutch, is diverting the oft-repeated and sometimes large forces required to brake to the engine and driveline components. This will wear them out prematurely, ESPECIALLY YOUR CLUTCH. This isn’t as big a deal in motorcycles, where the forces are smaller and the clutches are typically wet, but you will SMOKE your car’s clutch if you drive this way.
April 27, 2009 at 7:42 pm #18061WanderingRiderParticipantThanks for the warning, I’ll keep that in mind.
April 29, 2009 at 1:47 am #18096kirkParticipantThat was a very detailed explanation Eternal. Thanks for the insight.
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