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Two maintenance questions

romany

New member
There's a flat spot on my F650GS head bearings. How critical is this? It seems to begetting progressively worse. Should I bite the bullet and just switch it out?

Second questions regards the break rotors. Both the front and rear rotors are below the minimum standard. Local BMW guy says I could ride with them like this but if I traded it in they'd replace the rotors. I'm leaning toward replacing them.

Has anyone done this and did you use stock or aftermarket rotors? Wave rotors would look cool but do they offer any real stopping advantage?
 
I'd do both.
BMW doesn't give discounts any more, so I'd probably go with the aftermarket rotors. Big price difference and they are not worse. Probably no better, but not worse with a better price. I could like that.
dc

That head bearing has to be done just right. Don't botch that. And hardware for the rotors too.
 
I'm curious on the mileage on the F650GS. Also curious on how you felt the flat spot. Was it riding or maybe front wheel off the ground?
OM
 
A couple years ago I decided to pull my steering head apart ans service the bearings even though there was no detectable play or notchiness. I was suprised at how the lower bearing looked when I got it apart. If you can feel a flat spot, you really need to change the bearings.

P1010619.JPG

P1010620.JPG

I am going to pull it apart again next month and replace them again just because.
 
I had to replace the head bearings on my wife's twin. I bought the bearings at the auto parts store for much less than BMW wanted. The only issue I had was getting the lower bearing off the stem. It took a lot of work and I messed up the plate that sits under the bearing (part #314212345096).
Getting the races out of the neck was facilitated by using some stuff designed to loosen frozen bolts. I don't remember the name but it freezes the part, thus shrinking it, and they fell right out. I used the old races as a drift to tap the new ones back in.
Remember that you will need to readjust the bearings once they seat in, say a few hundred miles.
As I said, except for the lower bearing it wasn't that hard and made a definite difference in how the bike handled.
 
Removing the lower bearing from the stem is not so difficult and should nor result in damaging the tin shield. There are two holes under the bottom triple clamp that allow you to insert a pin punch and drive the bearing off. Alternatively, you can remove the cage and rollers from the bearing and use a bearing collar to grab the lip on the top of the race and remove the bearing in a press (as I did) or with a puller. The tin shield should be reusable with either method.
 
I'm curious on the mileage on the F650GS. Also curious on how you felt the flat spot. Was it riding or maybe front wheel off the ground?
OM

You cannot feel the flat spot when riding. If you put the bike on the centre stand and weight the backend until the front wheel lifts off the ground you can feel the spot as you slowly move the bars right to left. The fact spot is actually dead centre. Mileage is 64,000 kilometres or around 40,000 miles give or take a hundred.
 
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