Final drive, quick answer please

[Luma46]

I am just about to buy a 2009 R1200RT in excellent shape with 3900 miles on the clock from a BMW dealer. Bike looks like new, taking it for a test ride tomorrow. The only questionable thing that I could find was when checking the FD free play.

I couldn't feel any free play holding the rear wheel 9 to 3 a'clock. However holding it 12 to 6 a'clock, there was a bit of free play, hard to say how much. I did try couple new 1200GSAs on the floor and I could feel just about the same free play as well.

Should I be concerned or should I commit to purchase?

[dirtrider]

Morning Luma46

 

 

Personally, I would be more concerned if there was no free play on a cold bike. The spec is up to 1mm of wheel movement at the rim on a COLD drive. Too tight kills the bearing, a bit loose assures a not-to-tight bearing.

 

I guess I wouldn't want to see 1mm at the rim (cold) on a new bike but I wouldn't want at a real tight one either.

 

[Hall Vince]

And to counter the above. My 07 FD bearing went at around 22k, new bearings fitted and zero play, bikes now on 68k and still no play.

Personally, I'd buy it. You should have the dealer warranty with it any way and it is within the spec if below 1mm play at the rim.

Oh and the bearing replacment cost was 2 hrs at dealer and £300, covered by my extended warranty at the time.

\v/

[Hall Vince]

Just wondering why the mad looking smiley was in the top LH corner of my above post.

I must have brushed one of the options in the reply when using the android phone.

\v/

[RevRay]

Default smiley when tallking final drive .

[Luma46]

BTW, I have looked at the 1200RT RepRom and the permissible free play of 1 mm is not at the rim, but rater at less than half the distance of rim. That would mean at least 2 mm at the rim. Seams rather too large a free play.

Mine is definitely smaller, I'd say less than 1 mm at rim and strangely enough, only at 9 to 3 a'clock direction, none at 12 to 6 direction.

[dirtrider]

Morning Luma46

 

I don't know how you figure the measurement is taken 1/2 way up the rim but the (picture below) is directly from the 2009 BMW service manual. As you can clearly see the stinger on the dial indicator is resting on the outer rim with the indicator attachment point solidly mounted to the final drive housing.

 

 

[Marty Hill]

Your first post states that the 2 new GS's were the same. I would think that proves there is nothing wrong with the one your looking at. Chances of all 3 being bad are rather remote to put it gently.

[Luma46]

Looks like you are right. Somehow, I thought that the measurement is done through the hole where the gauge is attached... That would be half the rim distance from the axis.