R1200GS 72K service
Monday, July 30, 2012 [71,708 miles]
The bike is about 300 miles shy of 72,000 miles. I’m doing the service a bit early for two reasons; There is an SMBC dual sport ride in two weeks that I want to be ready for and the bike hasn’t been running all that well the last 200 miles.
On the way back from an SMBC breakfast in the north bay I stopped at Stinson Beach. The bike had been running well up to that point. When I left Stinson Beach the bike was buzzy. Literally. I first thought that I’d picked up a rock in my tires but eventually tracked down most of the buzz to a switch lead for aux lighting that was vibrating in the wind against the hand guard. Re-routing the wire out of the wind made things better, but the bike still wasn’t quite right. Just needs the valves checked, I thought.
Today I started my service by checking fault codes with the GS-911. The ABS reported low fluid levels a couple of times. A brake flush is scheduled for this service and the reservoir will be topped up with fresh fluid as part of that process. There was one additional fault logged: a bad cam speed sensor. That could certainly explain the way the bike felt. Tomorrow I’ll pick up a new sensor. But meanwhile….
I got out the ‘GS’ tools and started removing the valve covers to adjust the valves. Since the crash bars have been used (more than once) they need to be loosened to remove the valve covers. But wait… I’m also replacing the alternator belt. To do that I need to completely remove the crash bars.
I removed the front cover and started removing both sets of spark plugs when I found something interesting. One of the small (M6) screws that hole the cylinder hear to the cylinder was loose. I tightened it to the specified 9 Nm. The screw is just below the cam speed sensor. Coincidence?
I cleaned the alternator belt cover and the bash plate and set them out in the sun to dry. After removing the plugs I starting checking the valve clearances. The left side was perfect: no changes needed. The right side was almost perfect. I adjusted the upper intake valve to match the other three. It was a bit loose. This leads me to believe that the buzzy roughness I experienced was due to an intermittent cam speed sensor. At least I hope so.
Next I popped off the old alternator belt and put it in my tool kit as my new “backup” belt. I used the “turn the engine with a big crescent wrench” method to install the new belt. Easy.
I put the new plugs in the bike after verifing that they were gapped OK. This service the bike also got new valve cover “donuts”, the inner gasket. The old donuts were in good enough shape to keep them as spares. I used a dab of white lithium grease on the rubber tips of the coils before installing them. I think that makes the coils easier to remove when needed.
Next on the agenda is cleaning the after market (Uni) foam air filter that I use. Normally I’d remove the aluminum tank cover on the right side to pull the snorkel and access the air filter. However, since the tank has to come off the bike for brake flushing I pulled the tank now.
I removed and cleaned the filter. Inside one of the openings I found some butterfly remains and a twig that was larger than I thought would make it through the snorkel. I set the filter aside to dry. Tomorrow I’ll apply fresh filter oil and install it back in the bike. For now I threw a rag over the air box to keep dust and dirt out. I also re-installed the alternator belt cover after wiping down the front of the case with some WD-40 to remove some of the crud.