IDLES LIKE CRAP IN ROCK

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David R

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Something tells me that I will not be able to get this to idle smooth in ROCK.

It sounds terrible. Anyone tried to smooth it out?

I usually leave it in ROLL so when I stop, it does not shake and sputter while sitting at a light or when ever. Its smooth as can be. It should do that in ROCK too.

I am a life long mechanic. I remember folks telling me "its got a performance cam in it so this is the best it will Idle". Or "Its a performance engine" "Its supposed to sound like that".

Suggestions? Ideas?
David
 
I've noticed the same with mine. I just deal with the rough idle since I am always in rock mode unless I'm going to be on straight highway for awhile...then I put it in roll.
Not that big of deal to me tbh. I guess I just liken it to a old big block chevy with a nice cam in it lol. And to me thats not a bad thing
 
Sorry, this is redundant as I posted the same in another thread and hadn’t seen that you started this thread. The engineers intended it to be rough.

www.cycleworld.com

2021 BMW R 18 First Ride

Massive and nostalgic, BMW’s R 18 checks all of the boxes required for a American-style cruiser. Cycle World takes it for a first ride.
www.cycleworld.com www.cycleworld.com

"Three main bearings support the longitudinally mounted crankshaft—one between the 180-degree rod journals. This increases the offset between the cylinders—the left forward of the right—and imparts the classic “rocking couple” vibration exhibited by non-counterbalanced boxers of yore. Only it’s greater due to the wider separation of the connecting rods by that center bearing. Add to this the strong flywheel effect that amplifies the R 18′s left-to-right shake at idle—and it’s pure cruiser. And like old-time boxers, there is no balance shaft in this engine—BMW’s engineers wanted you to feel that flywheel effect and a strong engine pulse. They got it, now you have it."

If you, in your experience as a mechanic, think that it's TOO rough, maybe there's something amiss?
 
It’s not consistent. There is no reason for it to fire the way it does.
Smooth is what it should be. Instead it’s herkity jerkity.
Maybe the uninformed like the out of tune sound, but I do not.

It sounds like an Effin Harley
 
David R said:
It’s not consistent. There is no reason for it to fire the way it does.
Smooth is what it should be. Instead it’s herkity jerkity.
Maybe the uninformed like the out of tune sound, but I do not.

It sounds like an Effin Harley
Click to expand...
I truly think that sound is what BMW was going for. I'm used to old radial aircraft engines so it doesn't bother me. I also notice more crackling and popping when decelerating in rock mode.
 
David R said:
It’s not consistent. There is no reason for it to fire the way it does.
Smooth is what it should be. Instead it’s herkity jerkity.
Maybe the uninformed like the out of tune sound, but I do not.

It sounds like an Effin Harley
Click to expand...
Did you test ride before you bought? Has it changed between then and now? Do you know anyone else with one so you can compare. Is there a dealership nearby with a test bike you could ask them to fire up? Regardless of how you think it should idle, it was engineered to not be smooth. Specifically. Like they went out of their way to make it thus. But, from what I gather, yours could very well have a problem.
 
David R said:
It’s not consistent. There is no reason for it to fire the way it does.
Smooth is what it should be. Instead it’s herkity jerkity.
Maybe the uninformed like the out of tune sound, but I do not.

It sounds like an Effin Harley
Click to expand...
You want smooth try Rain mode.
What "Rock" have you been hiding under? Do some research! That is what it is designed to do.
You my friend ARE, "The uninformed"
Here's Your Sign.
Try Youtube. There are dozens, if not hundreds of videos that will explain it to you.
 
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TodkaVonic said:
Did you test ride before you bought? Has it changed between then and now? Do you know anyone else with one so you can compare. Is there a dealership nearby with a test bike you could ask them to fire up? Regardless of how you think it should idle, it was engineered to not be smooth. Specifically. Like they went out of their way to make it thus. But, from what I gather, yours could very well have a problem.
Click to expand...
I agree, Houston we have a problem.
Another loose nut behind the wheel.
 
My dad had a 1935 John Deere tractor. It was a parallel 2 cylinder. I guess it would be called an 180* crank, the pistons ran opposite of each other. When one was going up, the other one was going down, so when it fired, Cyl # 1 fired, then Cylinder #2 fired 180* later, then it went a turn and a half before firing again.
Pop Pop............Pop Pop..........Pop Pop Sort of like a 45* V twin.

We have pistons that fire exactly opposite of each other. 360* apart.

Just like the rest of the bike, some folks like it, some don't. I would prefer a smooth idle.

Yes, I know they did it on purpose. I get no joy watching a motorcycle shake at a red light.

Feeling the power pulses is enough for me.
David
 
Rock mode idles almost identical to my old '98 R1200C. The C did it all the time though.....no option to smooth it out. Doesn't bother me (and as Black Dog suggests, it wasn't a surprise), but I can see that it wouldn't be everybody's cup of tea.
 
tommymck said:
Rock mode idles almost identical to my old '98 R1200C. The C did it all the time though.....no option to smooth it out. Doesn't bother me (and as Black Dog suggests, it wasn't a surprise), but I can see that it wouldn't be everybody's cup of tea.
Click to expand...
The rough idle in Rock mode is not an unknown quantity.
It has specifically been used as a selling point for anyone who has paid attention to the R18 advertising and development for the last 2 years.
Bitching about the rough idle in Rock mode, is like buying a banana split then bitching about the banana hidden in the ice cream.
 
David R said:
My dad had a 1935 John Deere tractor. It was a parallel 2 cylinder. I guess it would be called an 180* crank, the pistons ran opposite of each other. When one was going up, the other one was going down, so when it fired, Cyl # 1 fired, then Cylinder #2 fired 180* later, then it went a turn and a half before firing again.
Pop Pop............Pop Pop..........Pop Pop Sort of like a 45* V twin.

We have pistons that fire exactly opposite of each other. 360* apart.

Just like the rest of the bike, some folks like it, some don't. I would prefer a smooth idle.

Yes, I know they did it on purpose. I get no joy watching a motorcycle shake at a red light.

Feeling the power pulses is enough for me.
David
Click to expand...

Could you elaborate on "We have pistons that fire exactly opposite of each other. 360* apart."?
 
Left cylinder fires, one turn of the motor, right cylinder fires.
Repeat.

One cylinder is compressing, the other is exhausting.
Both pistons go out at the same time. Good primary balance.

Most older parallel twins had both pistons move together. One fires on one stroke, the other fires on the next stroke. A 360* crank. The problem was they shook! Yamaha 650 is one I can think of. Honda 350, or the older 360. My dads CB 200.

Kawasaki came out with the Versys 650, It has a 180 crank like my dads John Deere. I bought one because the twins I had before that all shook like crazy because the pistons ran together. SO, the Versys fires like my dads John Deere, except at 11,000 RPM I would not notice. I rode that bike 14,000 miles in a couple years and traded it. It did vibrate, but it was a buzz, not a shake.

For now, I just leave it in Roll. I like the response in ROCK. I do not have the passenger back rest, so when the wife is on, I need to be gentle.

David
 
TodkaVonic said:
Could you elaborate on "We have pistons that fire exactly opposite of each other. 360* apart."?
Click to expand...
He is relying to reference 360* of crankshaft rotation.
He just does not understand that the "erratic" idle in Rock mode is both a design feature an intentional selling point that has been promoted for months before the first R18 hit the sales floor.
He would buy a Hellcat and bitch about the loud exhausts and poor gas mileage.
 
Enough, I don't like it. As a mechanic, when I hear an engine running and its not consistent or smooth, I think some thing is wrong. It usually is. I know its designed into the bike. Its an international selling point. Great. I understand it.
I do not have to like it.
Its not enough for me to not buy the bike, but ...... I don't like it. I read as many reviews as I could find. "it shakes more in ROCK than ROLL or RAIN".

Love it or leave it? :)

LOVE the rest of it.

I understand the power and torque of a straight 6 cylinder compare to a V 8. I get a 45* V twin is going to vibrate and run uneven. A 90* V twin has perfect PRIMARY balance. GM made the 4.3 V6 that fires at 90 and 270*. It sounds funny to me too. A boxer should be smooth as can be. Kind of like my R75/6. Smooth, even, quiet and consistent.

Why did we spend all kinds of time making sure throttle bodies or carburetors are to each in perfect sync other?

Over and out for this topic.
David
 
David R said:
It’s not consistent. There is no reason for it to fire the way it does.
Smooth is what it should be. Instead it’s herkity jerkity.
Maybe the uninformed like the out of tune sound, but I do not.

It sounds like an Effin Harley
Click to expand...
Perhaps you can trade it back in on your beloved R1200R that idles like a sit-on lawn mover. Better hurry then (-:
 
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