• Welcome, Guest! We hope you enjoy the excellent technical knowledge, event information and discussions that the BMW MOA forum provides. Some forum content will be hidden from you if you remain logged out. If you want to view all content, please click the 'Log in' button above and enter your BMW MOA username and password.

    If you are not an MOA member, why not take the time to join the club, so you can enjoy posting on the forum, the BMW Owners News magazine, and all of the discounts and benefits the BMW MOA offers?

2007 hexhead cam chain rattle

carrell

New member
2007 R1200 RT w/13k miles. at appx 5000RPM and above, when accelerating hard, I hear what I believe to be a chain slap. My best guess is that the noise comes mostly from the left side. valves are properly adjusted. any thoughts?
 
2007 R1200 RT w/13k miles. at appx 5000RPM and above, when accelerating hard, I hear what I believe to be a chain slap. My best guess is that the noise comes mostly from the left side. valves are properly adjusted. any thoughts?

Might be pinging. Are you using premium gas?
 
The knock sensors should back timing off to eliminate pinging.. unless one has failed.. (and don't know if that will trigger a warning light or not..)

Assuming the R1200R is similar, the knock sensor will trigger a fault, but you may never see it on the display!

Jim :brow
 
Annoying sound

Assuming the R1200R is similar, the knock sensor will trigger a fault, but you may never see it on the display!

Jim :brow

Definitely had the spark knocking on my R1200R w/ aggressive acceleration. Didn't think much of it really and I always use premium. Is that something that should be fixed? Didn't know about knock sensors but that explains why it only knocks on the initial hard acceleration and clears up on subsequent ones. Sound crazy?:D
 
Definitely had the spark knocking on my R1200R w/ aggressive acceleration. Didn't think much of it really and I always use premium. Is that something that should be fixed? Didn't know about knock sensors but that explains why it only knocks on the initial hard acceleration and clears up on subsequent ones. Sound crazy?:D
Actually - sounds crazy. The ECU on the R1200R is fast enough to retard timing on-the-fly, meaning if it detects pre-ignition, the next firing stroke will be retarded. It's the only way they can get away with 12.5:1 compression.

Something isn't right if you're feeling "knock".. pre-ignition usually isn't described as knocking.
 
Actually - sounds crazy. The ECU on the R1200R is fast enough to retard timing on-the-fly, meaning if it detects pre-ignition, the next firing stroke will be retarded. It's the only way they can get away with 12.5:1 compression.

Something isn't right if you're feeling "knock".. pre-ignition usually isn't described as knocking.

Knock maybe a poor description. What I have heard is pre-ignition. While the gas pump displays "Premium" I often wonder if I'm getting that. Not to slight those who work in the gasoline industry but there is room for error there.
 
Originally Posted by deilenberger
Actually - sounds crazy. The ECU on the R1200R is fast enough to retard timing on-the-fly, meaning if it detects pre-ignition, the next firing stroke will be retarded. It's the only way they can get away with 12.5:1 compression.

Something isn't right if you're feeling "knock".. pre-ignition usually isn't described as knocking.


Knock maybe a poor description. What I have heard is pre-ignition. While the gas pump displays "Premium" I often wonder if I'm getting that. Not to slight those who work in the gasoline industry but there is room for error there.

Actually that is the same thing. What you might be hearing is a tiny bit of preignition right off idle if you dog it too much as you launch the bike. IIRC the ignition will allow some knock under 1500 RPM, or about that.

If it is happening any other time, it is very likely your knock sensor is bad. This is not unheard of on the R1200.

Jim :brow

PS It wont always show a fault, but should on the diagnostic computer, or on the GS-911.
 
Actually that is the same thing. What you might be hearing is a tiny bit of preignition right off idle if you dog it too much as you launch the bike. IIRC the ignition will allow some knock under 1500 RPM, or about that.

If it is happening any other time, it is very likely your knock sensor is bad. This is not unheard of on the R1200.

Jim :brow

PS It wont always show a fault, but should on the diagnostic computer, or on the GS-911.

Jim, I occasionally get 2 or 3 "tinks" when quickly rolling on the throttle at about 3,000~3,500 rpm. This seems to happen only when headed up a significant grade. Since the noise stops almost immediately, can I assume it's pre-ignition and that the knock sensor is doing it's thing as designed? The bike is an '06 RT, run exclusively on 93 octane.
Tom
 
Jim, I occasionally get 2 or 3 "tinks" when quickly rolling on the throttle at about 3,000~3,500 rpm. This seems to happen only when headed up a significant grade. Since the noise stops almost immediately, can I assume it's pre-ignition and that the knock sensor is doing it's thing as designed? The bike is an '06 RT, run exclusively on 93 octane.
Tom


Very likely the same thing, and for the same reasons. If you are in 6th gear and at 3K RPM, and give it hard throttle, you are dogging it a bit.

Jim :brow
 
Last edited:
Very likely the same thing, and for the same reasons. If you are in 6th gear and at 3K RPM, and give it hard throttle, you are dogging it a bit.
Jim :brow

Usually in 3rd or 4th at that rpm - I generally don't goose it in 6th much below about 4,000. But it's so smoooth at 3k!

Thanks for your reply.
Tom
 
Back
Top