Lugging the engine

[deucedog]

I almost always use engine braking when slowing. I will downshift as the speed decreases making sure that the engine doesn't over rev. This is the first time that I've heard that this practice is a bad idea. Unless, of course, the down shift causes the engine to rev to the red line. You hear it all the time at rally's and bike nights. Someone will leave and blast full throttle down the road and then just let off the gas and let the bike slow down via engine braking. This, I believe, is a good way to cause damage. Be it by something letting go, or just excessive wear.

 

[Safehaven]

I almost always use engine braking when slowing. I will downshift as the speed decreases making sure that the engine doesn't over rev. This is the first time that I've heard that this practice is a bad idea. Unless, of course, the down shift causes the engine to rev to the red line. You hear it all the time at rally's and bike nights. Someone will leave and blast full throttle down the road and then just let off the gas and let the bike slow down via engine braking. This, I believe, is a good way to cause damage. Be it by something letting go, or just excessive wear.

I've been living in the Austrian Alps for 5 years. Even through I did not have my Harley at that time, I did drive around with a Ducati (M900). I can tell you for sure that you NEED to use engine braking while going downhill for any extended period of time. If not you'll overheat the brakes, which "can cause loss of control resulting in death or serious injury " (Little inside joke).

I don't think using the engine when no fuel is delivered is harmful, and from what I understand it can even be beneficial to the engine since it causes the cylinders to suck up some oil on the cylinder walls due to the low pressure in the combustion chamber (Cooling & Lubrication).

Off course, when the engine is turning the rings are rubbing and this creates a bit of wear in the long run.. But we all buy these engines to run them, right? I think engine braking, if uses with a bit of reason, is totally okay.

 

[glenalt]

In reading this thread I have come to this conclusion, I'm confused. I have always used engine braking when slowing down and to keep speed down on steep downgrades and reduce braking. This is the first time I have heard anything negative unless you are over revving. I'm not sure just what to make of this.

 

[whacko]

I am new to motorcycling.....have a 2 month old 2010 FXDC and took an MSF safety course to get my license. I have been using their method of engine breaking and it makes sense to me:

1. Don't rely completely on engine breaking to slow the bike to a stop....you could over rev the engine and lock up your rear tire without even hitting the rear break (Yes I did this once by accident my first week on the bike by accident by shifting down two gears my mistake....scared me to death but I was smart enough go grab the clutch before things got too out of control) again...thanks to the MSF course folks that instructed us on correcting that mistake quickly!

2. Always use a combination of down shifting (moderate engine breaking will occur) and front / rear brakes. If you simply apply breaks form say 45 mph to zero without downshifting as you go you will be in a situation that someone discussed earlier where you will not be able to apply power quickly if needed to avoid a problem.

This has worked for me....I don't have a tach on my bike but I keep the rpm's at a level where if I apply the throttle at any time the bike will accelerate smoothly without the lugging feeling and excssive vibration.

Glider does this sound right?

 

[Safehaven]

Lugging = when in to high a gear and you try to pull away puts loads of stress on Gear box and motor - Not good
Over revving = YOU CANT thats what a limiter is for as long as you do not hit this with regular occurance then you are not damaging the motor.
Downhills and low gear riding is different as the motor is under a different type of loading to Lugging you are using the compression of the motor to control the engine not the fuel, throttle hence you can go down a hill in a low gear and slowly gather speed but you will find that you are around 2000rpms when at the bottom and go to accelerate meainging you have momentum and correct rpms - no lugging

Good to read Im not losing my mind

 

[Troy1225]

My understanding:

Lugging = higher gear, low RPM

Engine Braking = lower gear, higher RPM

 

[Dr.Evil]

Lugging = when in to high a gear and you try to pull away puts loads of stress on Gear box and motor - Not good
Over revving = YOU CANT thats what a limiter is for as long as you do not hit this with regular occurance then you are not damaging the motor.

Can you over rev the engine by being in too low a gear, going too fast, when the rear tire is driving the engine?

I don't think a limiter would do much good for this but the rear tire may not be hooked up unless you feathered the clutch and tried to over rev the engine.

 

[Carroll B]

I always thought the rev limiter prevented the engine from exceeding a certain rpm by pulsing the ignition (the coil or spark to the plugs) or interrupting the ignition. I can't see how the rev limiter would prevent the engine from turning too many rpm.s since the rear wheel is driving the engine not the ignition system or fuel. I do not always downshift, but riding in the mountains I do use the engine to slow the bike down to prevent overheating of the brakes., That being said I make sure I am in a gear to keep the engine rpm's below 4500 or so. If you are spinning the engine over red line because the rev limiter is set too high or is defective or because you are using to low a gear when using engine braking you could still throw a rod or cause other internal engine damage.

 

[Dr.Evil]

I always thought the rev limiter prevented the engine from exceeding a certain rpm by pulsing the ignition (the coil or spark to the plugs) or interrupting the ignition. I can't see how the rev limiter would prevent the engine from turning too many rpm.s since the rear wheel is driving the engine not the ignition system or fuel. I do not always downshift, but riding in the mountains I do use the engine to slow the bike down to prevent overheating of the brakes., That being said I make sure I am in a gear to keep the engine rpm's below 4500 or so. If you are spinning the engine over red line because the rev limiter is set too high or is defective or because you are using to low a gear when using engine braking you could still throw a rod or cause other internal engine damage.

I'm glad you asked that, I was not up for challanging anything Hobbit knows. I am not expecting him to be wrong, but only to learn something new.