Help! R1150R light knocking when Warm

[Devo3136]

I just bought a 2002 BMW R1150R And to start with I am thrilled I think. When I start the bike everything sounds fine after it warms up to running temp it has a light knock on the left side at Idle, but seems to dissapear when you give it throttle. It seems to run fine and drive fine but once warm it has this little knock. Could it be a connecting rod? Like I said it dont do it till its warm. There is 18000 miles on the bike and it is beautiful. Any Help? Did I buy a lemon I just paid 5500.00 . Help!

[boxermania]

Sounds like the left cam chain tensioner, the early models were prone to what you are exeriencing. Check to see if it has been updated, maybe talk to the prior owner. Do a search on cam chain tensioner.

Not a big issue. Good luck and let us know how you made out.

[Karmøy]

This is a common NOT a problem on this R bikes......"light knock on the left side at Idle, but seems to dissapear when you give it throttle."

It is the LEFT air spjeld/valve(Dont no the eng.word)
Place your hand behind the air intake on the left side and gentle squees it...the NOCKING will go away...

No problem enjoy your bike,and drive safely.

[f4tweet]

Yes, it is a recalled lemon. I will offer you $5501. Seriously, there is nothing wrong. I hope you enjoy yours as much as I am enjoying my used 02 1150 with 30K miles on it.

[timl]

That sounds like the left side cam chain tensioner. On my 2004 I notice it when the bike is well warmed up and I'm decelerating to a stop with the engine idling.

BMW has an improved tensioner which supposedly fixes the noise. You can find the details on this site. However, it is considered mostly cosmetic.

[Devo3136]

Cool, so no problem riding it until I get the new chain tensioner? Where do you get the upgraded tensioner and is it really $270.00?

[CycleRob]

The camchain tensioner makes a clattering rattle type sound, not a knock. Yes, it could be a connecting rod bearing. 18,000 miles in 8 years works out to 2,250/year, not much riding. That low yearly odometer increase may have led the owner to change the oil every 2.5 years or so . . . . not good enough to prevent internal corrosion. Compounding the problem would be the likelihood of predominately short trips, which generate undesirably high levels of acidic oil contaminates. That acid caused corrosion can oxidize the rod bearing inserts, accelerating wear and the size of the oil clearance. That large clearance eventually gets large enough that with a hot engine and thinner oil, the bearing will knock. THIS is a bad bearing on a blown OilHead motor. HERE is another shot of that motor, taken in the BMW Atlanta Service on Dept June 9, 2009 when I picked up my wonderful new bike.

Also possible, but unlikely on a bike sold by a BMW dealer, is a large error on the TB synch at idle.

To put your fears at ease, visit the BMW dealer and ask their engine man to listen to yours running. He will know, by how it behaves with RPM increases and the throttle.

[Karmøy]

Is it realy 270$....Will rip of a lot more in Norway,will find that out to day.....expensive rattle.

[Railbender]

Cool, so no problem riding it until I get the new chain tensioner? Where do you get the upgraded tensioner and is it really $270.00?

No problem riding it until you replace the tensioner. I got mine from Rubber Chicken Racing for much less than $270.

http://www.rubberchickenracinggarage.com/chain.html

[Devo3136]

OK I rode it today about 60 miles seems to run fine, just when i slow to an idle does the sound come back. Ordered a chain tensioner at Rubber Chicken Racing for $80.00 thanks to Railbender i'll change it when it arrives and go from their.

[RwageR]

I just sold my 02 1150R that had 90,000 miles on her. She ran like a top and NEVER missed a beat. She knocked the whole way. It's not the cam chain tensioner. Don't worry about it. Go ride.

[Devo3136]

Got the cam chain tensioner upgrade today and installed it, what a difference, all I hear now is the valve train chuggin' along. No more knocking No death rattle at start up. I'm so happy now. Thanks for all your input Ya Done Good!

[bmwdave52]

"They all do that".