Downshifting

[damnpoor]

If you look in the owners manual you will see that the recommended downshift speeds are all at about 20 mph. 1st is 18mph if I remember right. Anyway, I always just let the engine coast down in the same gear I was already in until I hit about 25 mph then pull the clutch and shift all the way down to 1st.

I was talking to a very wise mechanic one day about stopping and I asked him whether I should use the brakes and save the clutch or use the engine and save the brakes. He said, "Save the ENGINE." In other words, use your brakes which are cheap to replace instead of putting additional strain on the engine by downshifting every time you come to a stop.

 

[SovietRobot]

I make sure I'm in first before I stop completely.
And I stay in first the whole time.

 

[SovietRobot]

If you look in the owners manual you will see that the recommended downshift speeds are all at about 20 mph. 1st is 18mph if I remember right. Anyway, I always just let the engine coast down in the same gear I was already in until I hit about 25 mph then pull the clutch and shift all the way down to 1st.

I was talking to a very wise mechanic one day about stopping and I asked him whether I should use the brakes and save the clutch or use the engine and save the brakes. He said, "Save the ENGINE." In other words, use your brakes which are cheap to replace instead of putting additional strain on the engine by downshifting every time you come to a stop.

I've heard that a lot and I think it's bull.
You're gonna have to downshift anyways, and with a sequential transmission, shifting down 4 gears without disengaging and engaging the clutch each time can actually hurt it.

You are not going to damage the transmission by properly shifting and using the engine braking ability.

 

[damnpoor]

I've heard that a lot and I think it's bull.
You're gonna have to downshift anyways, and with a sequential transmission, shifting down 4 gears without disengaging and engaging the clutch each time can actually hurt it.

You are not going to damage the transmission by properly shifting and using the engine braking ability.

It just depends on how you see things. I believe that saving revs now will add to the life of the engine in five years. If you don't plan on owning it for five more years or you have the cash for a new bike then it doesn't matter either way.

 

[dako81]

.... shifting down 4 gears without disengaging and engaging the clutch each time can actually hurt it.

.....

Depending on how fast you do it. If it is all at once at a slow speed, probably, but slowly over the period of the time you are decelerating to the stop, shouldn't. The oil friction on the clutch, and the movement from the chain spinning the output on the trans would keep everything relatively moving and lubricated to keep it functioning properly.

So yes, do not wait till the last second and slam down through all of the gears.

At all times, even when my clutch is disengaged, I try to be in a gear that would allow me to quickly and easily accelerate in a split second if I needed to. I always try to be in a good gear for the speed I am going, so I never get stuck in a difficult spot. So I'm constantly aware of my speed (sight around me), engine speed (sound/feel), and gear (memory).

 

[dean2287]

I'm with the downshifters movement. Be ready to drop the clutch at the speed you are going. If that Gixer boy had to get going suddenly he'd kill the motor and likely himself too.

 

[dako81]

It just depends on how you see things. I believe that saving revs now will add to the life of the engine in five years. If you don't plan on owning it for five more years or you have the cash for a new bike then it doesn't matter either way.

Engines don't really last for a certain number of revs. While the engine is running, without a load, it's actually not really wearing at all. When the engine has a load and is making power is when the wear occurs. Most professionals will say an engine has sort of a specific range of "horsepower hours" before it is worn out. So, an engine running at a high rpm, with little load, will last longer than an engine running at a lower rpm, with a higher load.

That's one reason to not lug the engine. More of the available power has to be used at lower rpm to accelerate, or overcome the load on the engine. So, it takes a higher percent of the available power, adding to the horsepower hours. If the engine were to take the same load at a higher rpm where more power was available, it would be using a smaller percentage of the available power at that rpm, adding less to the horsepower hours. Speaking generally. Make sense?

Hypothetical example:
If it takes 25hp to accel. from 30mph to 50mph in 15 seconds, and you do this through a range of 2500rpm to 4000rpm, and the average horsepower available across these rpm is 30hp, you've used ~83% of the engine's horsepower for 15 seconds.

Now, if you do the same acceleration over the same time from 6k rpm to 8k rpm and the average available horsepower across this range is 75hp, you've used 33% of the available horsepower for 15 seconds.

Much less stress on the engine.

OR, I could be spouting warm, dark brown chunky liquid all over the internet.

You can decide. lol!

 

[damnpoor]

Hypothetical example:
If it takes 25hp to accel. from 30mph to 50mph in 15 seconds, and you do this through a range of 2500rpm to 4000rpm, and the average horsepower available across these rpm is 30hp, you've used ~83% of the engine's horsepower for 15 seconds.

Now, if you do the same acceleration over the same time from 6k rpm to 8k rpm and the average available horsepower across this range is 75hp, you've used 33% of the available horsepower for 15 seconds.

Much less stress on the engine.

By this logic you could argue the engine will last longer if you always drive at 10K than if you always drive at 5K. That concept is something I've never heard and will have to consider though.

I don't so much think that an engine is born with X many revolutions in it's life. It's more like the way you ride affects how long and how well the engine will last. If I can save wear on the engine by not using the engine to brake then I'm going to do it. I can look at my brake pads and see the wear and replace them when necessary. I can't get inside my engine and measure the wear on the bearing races and cylinder walls. Maybe it doesn't hurt anything at all but if I can get some extra life out of the engine I'm gonna go for it.

 

[Stumbles06]

One thing to remember also, IF you go from say 40Mph and begin braking, don't slam it down to first and accidently let the clutch out too quickly, compression-lock will get ya, and it will bite hard. The GSXR may have a "slipper-clutch"... thus preventing comp-lock.

I always engine brake, change down -> blip the throttle -> release clutch... dunno about the saving fuel comment, but saves on brake pads :thumbup:

 

[chunkygoat]

Gas mileage is not an issue for me. I ride a bike, i get x3 the fuel economy that my car gets. But it is a high rev engine, and i notice i get the most efficiency out of my fuel between 6 - 8k rpms.

I'm not going to save myself 20 cents in gas at the expense of my engine or my brakes. Judging by everybody's opinions on the matter, its up to the rider's preference. Using a combination of brakes and engine braking is what works for me. Disengaging and engaging every gear when decelerating helps keep track of my gear and speed, saves my brakes, and seems to be the proper way to use the sequential gears - rather than flying down from 5th to 1st.

I am confident now in my technique. Although you may find yourself in a situation occasionally where you must drop multiple gears quickly, I will stick to using my engine and brakes when dropping speed - as it seems most logical to me.

Thank you all for the input.

 

[SovietRobot]

Every engine is built differently.

The engine on a ford focus or a 83 buick skylark is going to be built to loose tolerances for light duty, low rpm daily driving. So yes running one of those near redline all the time will probably decrease its lifespan.

The engine on our bikes and most jap bikes are built to extremely tight tolerances much like race engines. This is why you get a lot of metal shavings in the oil during break-in.

Simply put, these engines are made to be run at high rpm for long periods.
Lugging is bad for these bikes.
If you want a bike to cruise around at low rpm with plenty of grunt, buy a cruiser.

Everybody will tell you different break in preferences for an engine, but generally, the best way is to run it like you plan on running it forever.
For a race engine this means running it balls out. For a daily driver it means keeping the revs low and not being hard on it.

 

[Pickax]

A combination of a little engine braking while using the brakes seems to work best for me. I tend to shift down gradually and give myself reasonable access to 6k or so. It may be my imagination but the motorcycle just seems more stable at higher revs. When I get down to about 3500 or so (only when coming to a stop, really) it almost seems like it's struggling in some way. I guess that is really low on revs so I'm sure it plays into it a bit. The more the engine "pulls" the better the bike feels for me.

On my old GZ250 it seemed the other way around which I suppose makes sense. It quickly got to high revs in each gear and the bike wasn't meant to be a speed demon by any stretch of the imagination. It also seemed to need to need the gradual downshift of gears.

I don't know that there's a definitive answer on whether downshifting gradually is better or not. Having access to some decent acceleration is an obvious plus though and I think being able to safely move should you need it may be the most important element of all. Engine or brake wear be damned.

 

[Heather]

If I'm traveling at 40mph and come to a stop sign generally I don't shift, engine brake, shift, engine brake, shift, engine brake, shift, engine brake. I use my brakes and immediately shift to the appropriate gear- 1st. Sometimes I down shift, sometimes I coast, sometimes I'm accelerating towards a stop sign and hit the brakes. In traffic I'm more sensitive to this and wouldn't be caught in 5th a 5mph but when no one's around who cares? Sort of like pulling up next to a guy in minivan with a roll cage, 5 point harness, wearing a full faced race helmet and fireproof suit calling you reckless for not taking the same precautions. You can't really prove him wrong but you sure as hell can call him paranoid.

Question: When you downshift rapidly like this from 40 mph, do you ever have trouble getting it to downshift (shifter won't move)?

 

[sm00thpapa]

I do the same thing once my bike gets down to 15 MPH. I shift from 6th or any other gear down to first right before I stop the bike. This is what they teach you in the MSF BRC.

 

[fz6nick]

I do the same thing once my bike gets down to 15 MPH. I shift from 6th or any other gear down to first right before I stop the bike. This is what they teach you in the MSF BRC.

What if you have to speed up again real fast to avoid a car headed your way from behind and not stopping? Going 15pmh and letting out the clutch in 5th b/c you dont have time to go into first, not a good idea. You wont go anywhere.

If you shift each individual gear, you will be able to gas it out of the way each time

 

[sm00thpapa]

What if you have to speed up again real fast to avoid a car headed your way from behind and not stopping? Going 15pmh and letting out the clutch in 5th b/c you dont have time to go into first, not a good idea. You wont go anywhere.

If you shift each individual gear, you will be able to gas it out of the way each time

Well to be honest how many times has a car come up behind you and didn't stop? I'm just curious. Most riders say never so theres my point.

 

[fz6nick]

Well to be honest how many times has a car come up behind you and didn't stop? I'm just curious. Most riders say never so theres my point.

Way more often than you think. Try getting some miles on that puppy and see what happends when cars cant see motorcycles. What tends to happen to me the most is: When I dont go through a yellow light. Which i try never to do. The car behind you is probably going to assume your going and try to go also.

This is also why I always keep it in gear at a stop light

 

[sm00thpapa]

Way more often than you think. Try getting some miles on that puppy and see what happends when cars cant see motorcycles. What tends to happen to me the most is: When I dont go through a yellow light. Which i try never to do. The car behind you is probably going to assume your going and try to go also.

This is also why I always keep it in gear at a stop light

Well in that case I know what you mean. If the cager isn't tailgating you, which they most do, then it may be a problem. But I am always in first at a light or maybe once in awhile in neutral so I can take a breather and lift my shield.

 

[fz6nick]

Well in that case I know what you mean. If the cager isn't tailgating you, which they most do, then it may be a problem. But I am always in first at a light or maybe once in awhile in neutral so I can take a breather and lift my shield.

Not trying to argue btw. just trying to help someone avoid situations ive been in.

If i know its going to be a long light and the car(s) behind me have stopped already i will put it in neutral. I normally lift my visor in the middle of slowing down instead of stopped. nice to get that breese in your face.

 

[sm00thpapa]

Not trying to argue btw. just trying to help someone avoid situations ive been in.

If i know its going to be a long light and the car(s) behind me have stopped already i will put it in neutral. I normally lift my visor in the middle of slowing down instead of stopped. nice to get that breese in your face.

Oh it's all good man. I do it while I'm stopped cause I'm a noob and don't want to take my hands off the handle bars till stopped. While I'm riding I'll remove my hand from the clutch just to rest it. I still have a lot to learn and thanks for the pointers.