Is 700GS head bearings same as 800GS?

[soupdragon]

Hi everyone. I've just bought a 2012 f700GS with 19k miles on it. The previous owner fitted new head bearings at 18k himself. I've read lots of threads on here about the early failures on f800GS and was wondering if the 700 suffers as much. Are they the same design? Do up-side-down forks put more stress on the bearings? Should I check that they have been tightened correctly? Could they be replaced with old fashioned ball bearings instead? I have never had any problems with any bike over 40 years that had simple ball bearing headsets.

 

[Ash]

www.maxbmwmotorcycles.com

 

[Ash]

Looks like 650 / 700 are the same but 800 are different....

 

[Ash]

I just bought a 2011 650GS & new bearings fitted at 12k miles looking at the service history...

 

[Keith Chapman]

Realoem gives the same part number for 700 & 800 bearings 31427663941 size is 28x52x16

Ash, it looks like the 650 & 700 bearing 5070 has been superseded to 3941 the same as the 800.

 

[SteveT]

Not a F700GS but a F658GS

When I got the 4 year old bike, 18 months ago with just 8k miles on it from it's 1st owner, I dropped the head stock and checked the bearings. Finding nowt wrong with them I applied liberal amounts of quality "water proof" grease (not all grease is "water proof"), refitted everthing as per the manual and have coverd another 8k miles - many, many off road, without any sign of notcheness or loosness. Bikes just passed another MOT this morning .

However, the F800GS does treat it's bearings differently in my experience, having just done them on my '10 plate F8GS. The bikes got just under 24k miles on it and when I dropped the yolks there were witness marks on the steering stem that leads me to believe that the bearings had been changed at least once before the bike came into my ownership last year (no record of them being changed in the extensive service history I got with the bike ).
I changed the head bearings on my previous F8GS at 19k miles, but there was no sign of them having been changed prior to my doing them, so there is no real "pattern" to when they go, they just seem to go more frequently than on other bikes that I've owned.

Just my ramblings

SteveT